I recorded the calibration program from HDNET and, not to sound like a complete idiot, but, how do you use it??? I have the Home Theater Magazine calibration disc that I used with success for my DVD player input, and I was going to use the HDNET to set my cable input. But the screens don't seem all that similar to the disc I've used and I don't understand how to use them other than the overscan one. Are there instructions on the web or something? Or is the HDNET program similiar to other calibration discs so maybe I can use those instructions?? Help a dummy, if you would please!

Hmmm, I thought the HDNet calibration program (the one played around 7 or 8 AM) had an audio track that described how to make the adjustments for each of the screens. The one I saw the other day described how to do these coarsely without any filters.

hmmm, the volume WAS kinda low...maybe I didn't hear it? I'll watch and try listening this time. I may feel really stupid...

http://www.smartcalibration.com/hdnetpatterns.html

Thank you jstoddard, that's just what I was hoping to find!! Thanky, thanky.

This is my first time looking at the HDNet test pattern. Captured on my HD DVR, Verizon FiOS (6:50 AM EDT on Sunday, listed as "Off Air" in the program guide).

Has anyone verified the overscan pattern? The Smart Calibration LLC web site specifically states that the overscan is not very accurate: http://www.smartcalibration.com/hdnetoverscan.html For horizontal, I can only see down to the "10" on the edge, where it should be at "4". Vertical is down to 4, where it should be 3, and it seems to be a bit offset from center.

My Verizon FiOS STB is the only HDMI source I have, so I jumped on the chance to record something that's a known reference. Connected to a SamSung HL-R6768W (DLP).

For now, I just set the user adjustments to what I have on the component inputs (Digital Video Essentials, DVD player). The HDMI and component inputs lock out the tint (as they should) and the sharpness is enabled but doesn't seem to have any effect (I set it to zero).

Someone at HDNet has a sense of humor. The "resolution wedge" as I see it called on another thread has a text area:
8 - If you can read these
9 - last few lines, your display
10 - is better than mine.

How do you convert the numbers (1 -11) to lines of resolution?

Being that this is my only "true" HDMI source (see below), should I try a more serious calibration with just this pattern, or, leave things alone and use my component input settings? The overscan seems a bit off- how close is it? I may have to go into the service menu unless someone has a way of tweaking the Verizon STB HDMI output(?). How do I know that it's not the STB with the problem?

I connected my PC to the HDMI input via DVI / HDMI cable, but that's also overscanning. A lot. There are a number of users on AVS forum complaining about this also and the going opinion is that it's an NVidia software driver problem. That leaves me with the STB as my only reference.

To use the resolution wedges (last 4 mins) and obtain a maximum effective horizontal resolution figure I use this technique (http://www.avsforum.com/avs-vb/showthread.php?postid=5175424#post5175424). Many AVSers report similar readings (<1300 lines), apparently from STB limitations within many cable systems, perhaps coupled with factors such as rate shaping (http://www.avsforum.com/avs-vb/showthread.php?p=8011489&&#post8011489). Vertical rez (horizontal wedges) are the line-blur number X 100; pressing pause (8300HD) with my 1080i CRT displays one TV field or half-frame, roughly halving vertical resolution. Posts of measurements are useful. -- John

Thanks. Although painfully obvious, you reminded me that I shouldn't take these measurements in "pause" mode. No problem to help out here:

Display: Samsung HL-R6768W (67" DLP), room lighting = low ambient
Source: Motorola QIP6416-2 HD-DVR, Verizon FiOS, 1080i, HDMI interconnect.

Vertical resolution (horizontal wedge): 950 = 9.5 (playing) * 100, 750 = 7.5 (pause) * 100
Horizontal resolution (vertical wedge): 1,333 = 7.5 (pause or playing) * 100 * (16/9)

Note that this is Verizon FiOS (fiber optic), not "RF" cable TV. You may start to see an increase in postings for FiOS sources as it's getting very popular.

I'll need to devote some time to look at my service menu overscan options. For the weekend.

I'll also have to think about the brightness and contrast adjustments. That 0 - 9 strip at the bottom of the color bar pattern is really hard to use. I can't see much difference except at the extremes. Maybe I should just leave things at the component input settings. On the plus side, there's absolutely no problems with convergence :).

Display: Samsung HL-R6768W (67" DLP), room lighting = low ambient
Source: Motorola QIP6416-2 HD-DVR, Verizon FiOS, 1080i, HDMI interconnect.

Vertical resolution (horizontal wedge): 950 = 9.5 (playing) * 100, 750 = 7.5 (pause) * 100
Horizontal resolution (vertical wedge): 1,333 = 7.5 (pause or playing) * 100 * (16/9)

Note that this is Verizon FiOS (fiber optic), not "RF" cable TV. You may start to see an increase in postings for FiOS sources as it's getting very popular.

Many thanks. That's the first FIOS horiz. rez measurement I've spotted. With all the reports of better PQ, perhaps that's only limited to SD; that is, FIOS may provide a higher bitrate per SD channel, nearly maximizing the SD PQ potential from programmers. Your 1333 horiz reading nearly matches this ~1335 line (http://www.avsforum.com/avs-vb/showthread.php?p=8865051#post8865051) fairly recent reading from someone on NYC's TWC with a 1080p Ruby FP and 8300HD. Have only seem one post (http://www.avsforum.com/avs-vb/showthread.php?p=8509731&&#post8509731) indicating ~1920 lines from HDNet--someone with an 8300HD, 1080p RPTV, and on a smaller Calif. cable system. -- John

P.S. Might compare the pluge within the color bars with the later gray-background pluge within the resolution wedge section. Quite a difference here.

I took another stab at the pluge within the color bars. That's the 0 to 9 strip at the bottom (just in case I have the wrong pattern :)). The instructions at Smart Calibration LLC say that this pattern goes to "10", but I don't see it. Here's how I adjusted:

Brightness: Turn up until the last block on the right (after 9) just becomes visible above the "HDNet" black logo to the right. I used the logo since it's very easy to match against the block reference. Start turned all the way down and bring up until it just comes out of the background.

Contrast: Adjust contrast until the "0" in the white just appears. Start high and bring it down until you can see it (barely). At the high setting, it's blended with the block. As you bring brightness down, the "0" becomes very slightly gray compared to what it was and you can then see it.

Working backwards, the Smart Calibration LLC instructions say essentially the same thing, but this description works better for me.

Sorry, but there is no way I can compare it to the resolution wedge pluge. I'm doing this by eye and there's no black / white references that I can use, like an embedded number or bar. However, it looks darn nice after I made some adjustments with the numbered pluge bar.

Preliminary results, HDMI input:
Brightness: 50 (factory default = 50)
Contrast: 50 (factory default = 80)

I took another stab at the pluge within the color bars. That's the 0 to 9 strip at the bottom (just in case I have the wrong pattern :)). The instructions at Smart Calibration LLC say that this pattern goes to "10", but I don't see it.

Maybe you just made a minor mistake in your post and flip-flopped them, but you should be using contrast to adjust the white level and brightness to adjust the black level. As contrast decreases your whites become gray; as brightness increases your blacks become gray. Turn brightness up high enough and you should see the 10.

i have noticed that you can not the 10 if you are using component cables, you can only see the 10 if you are using hdmi

EricM407 - Sorry about that. You are correct, of course. I checked my notes. Was doing the procedure OK, but got flip-flopped during the post :o. I updated the post.

Dewar1234- Thanks for the tip. As for the "10", I went crazy looking for it. I was going to to post that I just couldn't see it and ask what's wrong. I took your tip and checked the S-Video output, also connected to the STB. Sure enough, there's the 10!

Maybe it's flip-flopped on this Motorola FiOS box. Why can I see it on an analog output but not HDMI? I'll ask around the other forums (there's a thread on this STB).

Do all HDTV's (LCD type, Plasma, and Rear-projectors) need calibration?

Why can I see it on an analog output but not HDMI? I'll ask around the other forums (there's a thread on this STB).

Out of curiosity, were you using a fixed resolution on HDMI or stretching the aspect ratio? I know my SA 8300 HD DVR messes with the black level if I use the box's scaler.

If you are not seeing the 10, then something is clipping black - most likely is some "advanced" user setting in the display and is not likely to be the STB.

RE: Overscan pattern, I believe that it has never been fixed, but don't know for sure.

If you are not seeing the 10, then something is clipping black - most likely is some "advanced" user setting in the display and is not likely to be the STB.

I just checked my SA 8300 (w/Passport), and it is definitely the problem. I can make the 10 appear and disappear just by changing Aspect Ratio in the More Settings menu. When it's gone, no brightness/gamma/black corrector setting on the TV makes it come back. I wouldn't be surprised if other STBs had quirks.

I just checked my SA 8300 (w/Passport), and it is definitely the problem. I can make the 10 appear and disappear just by changing Aspect Ratio in the More Settings menu. When it's gone, no brightness/gamma/black corrector setting on the TV makes it come back. I wouldn't be surprised if other STBs had quirks.I don't have Passport, so I don't know what you mean by changing aspect ratios. The aspect ratio should be fixed on 1080i. The cable box does not manipulate the digital values (Black = 16, White =235), so I still don't think that has anything to do with it.

I wouldn't be surprised if other STBs had quirks.I got the "10" to appear in the pluge bar pattern. The STB, Motorola QIP6416-2 (Verizon FiOS), has an "Advanced HDMI Setting" in the user setup menu called Color Space. The default is to set it to YCC 4:4:4, but there is an alternate setting of RGB.

The "10" appeared as soon as I changed the color space from YCC 4:4:4 to RGB. I also found some postings in the Motorola QIP6416 thread that discuss this. Turns out that YCC 4:4:4 clips the white levels. http://www.avsforum.com/avs-vb/showthread.php?p=9575259&&#post9575259

It's really tough to set the contrast correctly, as the "0" doesn't appear into the white background as cleanly as the "10" fades into the black. I'll have to experiment.

My display didn't have any problems using the new setting, but I can definitely see a difference in the program material (brightness/contrast settings still up in the air). Would it adapt to the new color mapping by itself? IOW, does it know that I'm in RGB instead of YCC?

Using the HDNET test pattern as a guide to set my controls results in my brightness (white balance) setting at a highter level (10 more) than with the Digital Video Essentials disk. When checking out films it appears to be too bright to go by this bar. So i'm not sure what they intended. And to set color properly from the color bars you need to be able to put up blue bars in order to calibrate. The only thing I found useful was the overscan settings . The convergence screens are only useful for the older sets since DLP and other newer models do not use manual convergence.

Using the HDNET test pattern as a guide to set my controls results in my brightness (white balance) setting at a highter level (10 more) than with the Digital Video Essentials disk. When checking out films it appears to be too bright to go by this bar. So i'm not sure what they intended. And to set color properly from the color bars you need to be able to put up blue bars in order to calibrate. The only thing I found useful was the overscan settings . The convergence screens are only useful for the older sets since DLP and other newer models do not use manual convergence.I assume that you are using different inputs for the DVE disk and the HDNet (one is cable or sat STB, the other is a DVD player) - so it is reasonable that there are different settings for each (particularly in setting the black level).

Also, what do you mean by "white balance" in the statement: in my brightness (white balance) setting ?

I have excellent correlation between setting black level and peak white on the HDNet patterns and using my Accupel HD Signal Generator on the same input on several customer's sets (as well as my own). Granted, the color bars are not ones that are easy to use, but the 0 to 10 bar is excellent.

I don't have Passport, so I don't know what you mean by changing aspect ratios. The aspect ratio should be fixed on 1080i.

It's not. Setting it to either 4:3 or 16:9 you can still stretch and zoom with it. This is separate from what the TV itself it can do, which can result in some weird combinations.

The cable box does not manipulate the digital values (Black = 16, White =235), so I still don't think that has anything to do with it.

I don't know exactly what the cable box is doing. All I know is blacks are getting crushed to make that 10 disappear, and it's without a doubt happening before it gets to the TV.

It's not. Setting it to either 4:3 or 16:9 you can still stretch and zoom with it. This is separate from what the TV itself it can do, which can result in some weird combinations.In most cases (I don't know of exceptions) if 1080i is fed to the TV, the TV automatically displays it ONLY at full screen. But you are talking about setting the 8300. I'm at a disadvantage here, not being familiar with Passport - but it is hard for me to imagine the 8300 having the ability to actually SHRINK the image from 16:9 to 4:3 - UNLESS the 8300 is set to SD (I do this all the time in order to make Anamorphic DVDs from HD programs). Now IF you have it set to SD and then somehow change to HD, I wouldn't be at all surprised that black levels change on your TV.

Just trying to help.

In most cases (I don't know of exceptions) if 1080i is fed to the TV, the TV automatically displays it ONLY at full screen.

I think we have the same TV, and I also think it can squeeze 16:9 1080i content into a 4:3 frame. Just set it to normal instead of full?

But you are talking about setting the 8300. I'm at a disadvantage here, not being familiar with Passport - but it is hard for me to imagine the 8300 having the ability to actually SHRINK the image from 16:9 to 4:3

It can't. It can only stretch it or zoom it - it will still fill up the screen, just warped, enlarged, or normal. What happens when you set it to 4:3 and you have 16:9 content on a 16:9 TV is... nothing... except that the black level changes. If you had a 4:3 TV and did this, then it would probably add gray bars top and bottom to preserve the aspect.

Gray is the only option with Passport, which is why some people set it to 4:3 even though they have 16:9 TVs. They want their 4:3 SD content displayed without the box adding its gray bars. They'll still have black bars, of course, or maybe even black bars around gray bars, if they get the wrong mix of settings. But 4:3 content in a 4:3 frame with black bars can be had out of this thing if you try hard enough. You're probably even more confused now than you were, sorry.

- UNLESS the 8300 is set to SD (I do this all the time in order to make Anamorphic DVDs from HD programs). Now IF you have it set to SD and then somehow change to HD, I wouldn't be at all surprised that black levels change on your TV.

No, I'm staying in HD 1080i the whole time. To make a long story short, the box is crushing blacks with certain aspect settings.

My Motorola QIP6416-2 STB (Verizon FiOS) is crushing blacks with no zoom, full 16:9 HDMI resolution (earlier post). They are restored when I go from the YCC 4:4:4 color space to RGB. Why?

Many thanks. That's the first FIOS horiz. rez measurement I've spotted. With all the reports of better PQ, perhaps that's only limited to SD; that is, FIOS may provide a higher bitrate per SD channel, nearly maximizing the SD PQ potential from programmers. Your 1333 horiz reading nearly matches this ~1335 line (http://www.avsforum.com/avs-vb/showthread.php?p=8865051#post8865051) fairly recent reading from someone on NYC's TWC with a 1080p Ruby FP and 8300HD. Have only seem one post (http://www.avsforum.com/avs-vb/showthread.php?p=8509731&&#post8509731) indicating ~1920 lines from HDNet--someone with an 8300HD, 1080p RPTV, and on a smaller Calif. cable system. -- John



John, these measurement are dicey at best. We have no idea what the display device or receiver that people are using are really capable of. Until we know for certain that a given display is indeed capable of 1920 horizontal resolution, I don't put much stock in these numbers. We've seen in recent display reviews that displays that 'should' be capable of 1920 horizontal are actually displaying far less than that.

I switched from D* to FIOS and I can tell you with 100% certainty there is a quantum leap in picture quality in both HD & SD. This applies to areas such as detail, macroblocking, color purity etc.

John, these measurement are dicey at best. We have no idea what the display device or receiver that people are using are really capable of. Until we know for certain that a given display is indeed capable of 1920 horizontal resolution, I don't put much stock in these numbers. We've seen in recent display reviews that displays that 'should' be capable of 1920 horizontal are actually displaying far less than that.

I switched from D* to FIOS and I can tell you with 100% certainty there is a quantum leap in picture quality in both HD & SD. This applies to areas such as detail, macroblocking, color purity etc.Ken, good comments. Reducing bitrate does not necessarily result in reduced resolution - particularly in static images. One (DirecTV) can intentionally reduce resolution as a first step to reduce bitrate, but it is not what is usually done.

Another, often overlooked issue in resolution is that pixels and resolution are not exactly the same thing. Yes, the higher the number of pixels, the greater the potential resolution - but 1920 pixels, does not mean 1920 lines of resolution.

I believe that the HDNet resolution patterns are in terms of TV Lines and really are lines per picture height. So it is not reasonable to expect to see 1920 lines of resolution.

Resolution is a complex, and often misunderstood subject. Rather than try to explain it (I've tried, but really cannot do it well) I've found this excellent explanation of resolution. (http://jkor.com/peter/tvlines.html)

John, these measurement are dicey at best. We have no idea what the display device or receiver that people are using are really capable of. Until we know for certain that a given display is indeed capable of 1920 horizontal resolution, I don't put much stock in these numbers. We've seen in recent display reviews that displays that 'should' be capable of 1920 horizontal are actually displaying far less than that.

I switched from D* to FIOS and I can tell you with 100% certainty there is a quantum leap in picture quality in both HD & SD. This applies to areas such as detail, macroblocking, color purity etc.
That's all in your opinion. Puzzling why a FIOS reading of 1333 would prompt such a sweeping statement since FIOS uses cable TV technology in part and ~1300 is what many cable users are reporting. Most 1080p reviews I read do show 1920 line capability, and a 1080p display was used above. Someone owning a 1366X768 plasma display might get a similar reading (effective horiz. rez). Since FIOS provides HDNet and many are acquiring 1080p displays, all that's needed are measurements. That is, the "S" part of AVS. :) -- John

Another, often overlooked issue in resolution is that pixels and resolution are not exactly the same thing. Yes, the higher the number of pixels, the greater the potential resolution - but 1920 pixels, does not mean 1920 lines of resolution.

I believe that the HDNet resolution patterns are in terms of TV Lines and really are lines per picture height. So it is not reasonable to expect to see 1920 lines of resolution.
Yes, HDNet resolution wedges provide lines per picture height (horiz. rez) or lines top to bottom (vert. rez). Just multiply by 16/9 for lines/HD picture width. Pixels are often used in a computer context and don't represent sampled signals as with HD video. In the broadest sense of pixels (picture elements), each HDNet line, if you zoom in on it, is formed by individual pixels.

Over the years I've reported and posted a few 1920X1080-line readings obtained from HDNet, including quotes from sources, such as Gary Merson's review of the first 1080p RPTV years ago. But if no one can again obtain this resolution, and HDNet won't confirm that's what they're putting out, that would raise suspicion. -- John

That's all in your opinion. Puzzling why a FIOS reading of 1333 would prompt such a sweeping statement since FIOS uses cable TV technology in part and ~1300 is what many cable users are reporting.-- John

I'm not sure what you mean by a 'sweeping statement'. If you're referring to my overall assessment of PQ on FIOS, I am in the overwhelming majority on this point. We also have an owner of a 1080p display and FIOS user reporting that he did indeed get a horizontal resolution of 1920 from one of his two measured channels. So FIOS is indeed passing the full rez signal when it's provided by the broadcaster.

There's no way I would lump FIOS with the typical 'cable TV technology' since their bandwidth is almost unlimited relative to typical cable systems. This enables FIOS to provide a greater bit rate, better resolution and an overall better PQ. If you read the myriad of posts from people that switched from "XXX' system to FIOS, you'll find the overwhelming majority reporting the same thing. :)

Do all HDTV's (LCD type, Plasma, and Rear-projectors) need calibration?Yes! If you read these posts (including the "stickies" at the top of this forum), you will discover why this is true. Most of the displays, of the types you mentioned, are set way too bright, with exaggerated colors, in order to sell these in the stores (they grab the customers attention).

Some display's default settings are better than others, but they all need calibration to some degree. Also, each input source has to be calibrated (your DVD player will have different calibration settings from your TV source, etc.).

I'm not sure what you mean by a 'sweeping statement'. If you're referring to my overall assessment of PQ on FIOS, I am in the overwhelming majority on this point. We also have an owner of a 1080p display and FIOS user reporting that he did indeed get a horizontal resolution of 1920 from one of his two measured channels. So FIOS is indeed passing the full rez signal when it's provided by the broadcaster.

There's no way I would lump FIOS with the typical 'cable TV technology' since their bandwidth is almost unlimited relative to typical cable systems. This enables FIOS to provide a greater bit rate, better resolution and an overall better PQ. If you read the myriad of posts from people that switched from "XXX' system to FIOS, you'll find the overwhelming majority reporting the same thing. :)

Ken, I don't doubt at all the many reports of improved PQ from FIOS, although as I recall a number of the them emphasize SD. They've all made me eager from day 1 to try it out, too, although Verizon may not reach my location for a while. Sweeping statement refers to, in effect, suggesting (with all the reasons given) that folks with the right displays can't measure HDNet's resolution wedges and report effective resolution accurately. 'Right display' means a 1080p or equal if you assume HDNet's resolution wedges originally (satellite uplink/downlink) provide ~1920X1080, and you further assume no limition of that 1920X1080 in resolvble detail by your program delivery source, tuner, and display hardware. And still, if FIOS effective rez is typically ~1300 lines, displays with ~1366-pixel horizontal resolution should be adequate.

I've only seen one report (above) of measured effective resolution from FIOS with HDNet. That's GeekGirl's 1333-line measurement above. Registering (not measuring) a FIOS delivered format resolution of 1920X1080 versus 1280X720p (etc.) for any number of channels, as we all know, is entirely different. A full 1920X1080 HD-format signal can deliver zero effective resolution if it's an all-gray screen--or any resolution between zero and 1920. Mixing DirecTV's HDLite into the discussion seems misleading here because their reformatting to 1280X1080 totally lops off any details >1280.

Making this HDNet resolution-wedge measurement is no more difficult than taking a temperature reading--well, maybe in C with conversion to F. So FIOS or cable subscribers with DVRs can record HDNet's Sunday* 6:50 am ET pattern, watch the last 4 mins (of 10), observe the 'grayout' merge point where vertical converging wedge lines can no longer be resolved, then multiply the number beside the wedge by 100 (lines/picture height), then by 1.78 to obtain lines/16X9 picture width.
*(Or maybe Tuesday same time? They seem to switch. Check at HD.Net).

If other typical FIOS readings are ~1300 lines, maybe the cable-type STBs used are a limitation. And perhaps if FIOS assigns higher bit rates to both SD and HD, and presumably doesn't rate shape (http://www.avsforum.com/avs-vb/showthread.php?p=8011489&&#post8011489) with requantization like bandwidth-limited delivery systems, that accounts for the better PQ with motion video compared to static test-pattern images that have very limited bit rate requirements. -- John

I'm not sure the Samsung HL-R6768W is an ideal display for measuring horizontal resolution since it only has 960 horizontal pixels on the chip. Does anyone have any data on whether it can actually achieve an effective resolution of 1920 lines/picture width using the "wobulation" technique?

Btw, the method of multiplying the vertical wedge measurment by 16/9 to get # of vertical lines/picture width only works if you have square pixels. My display does not (16x9 = 1024x768) so when I measure the vertical wedge I get 7.5x100x1.33=1000 which is what I should get.

edit: An additional note about FiosTV, the HDNET stream is 5C encrypted so I can't probe the mpeg stream for format but unencrypted streams like FOODHD and MTVHD delivered at the same bit rate (18 Mbps) is 1920x1080.

I'm not sure the Samsung HL-R6768W is an ideal display for measuring horizontal resolution since it only has 960 horizontal pixels on the chip. Does anyone have any data on whether it can actually achieve an effective resolution of 1920 lines/picture width using the "wobulation" technique?
A good point that also occurred to me earlier. One of the few 1080p display (RPTV) reviews I've read mentioning failure to resolve 1920 lines horizontally was a Mits model (http://archive2.avsforum.com/avs-vb/showthread.php?p=6896427&&#post6896427) tested by CNET. But a few threads, 1-2 years back in the RPTV forum, included screen shots of full 1920 line resolution with a number of wobulation-chip DLP displays. And all the more recent reviews I've seen of wobulation or SmoothPicture (TI's term) 1080p displays have published 1920 line readings. Maybe owners or anyone interested in pinning down the Samsung capabilities can confirm whether it, too, has 1920 resolvability from reviews; (no it doesn't; see my edit below). And of course a DIY confirmation of 1920X1080 resolution for any display is possible with the latest 1080i test DVDs mentioned in this forum, or using the variety of computer software programs generating 1920-line patterns. One reading of 1333 line effective resolution using FIOS should only be a starting point and clearly needs more confirmation with additional measurements.

Btw, the method of multiplying the vertical wedge measurment by 16/9 to get # of vertical lines/picture width only works if you have square pixels. My display does not (16x9 = 1024x768) so when I measure the vertical wedge I get 7.5x100x1.33=1000 which is what I should get. Interesting point. Multiplying by 1.33 is also the factor used for converting 4X3 NTSC resolution measurements/picture height into resolution lines/picture width. Seems best, then, to use a 1920X1080i/p display for confirming full (test-pattern) resolution, or at least 1366X768 displays for measuring suspected effective test pattern resolutions of typically ~1300-lines for STBs and/or delivery systems. If HDNet's pattern was very crisp out to 1366 lines, then you'd want to try a higher-resolution display to measure STB limitations. (DirecTV's reformatted HDNet resolution to 1280X1080 from 1920X1080 isn't suitable either.)

Presumably, then, the 7.5X100X1.33 reading (overlooking scaling) would mean, with a square-pixel 16X9 display, this HDNet reading, if that's what it was, would be 1335 lines (7.5X100X1.78). If so, that's a typical cable STB reading, especially using a HDMI hookup with a 1080p display (as here (http://www.avsforum.com/avs-vb/showthread.php?p=8865051#post8865051).) Then again, measuring 1335 with a 1024-limited display doesn't make sense!

edit: An additional note about FiosTV, the HDNET stream is 5C encrypted so I can't probe the mpeg stream for format but unencrypted streams like FOODHD and MTVHD delivered at the same bit rate (18 Mbps) is 1920x1080.
Assume most know that the format resolution of 1920X1080, reported on many STBS or cable-STB diagnostic modes, differs entirely from measured effective resolution (http://archive2.avsforum.com/avs-vb/showthread.php?p=5667245&&#post5667245). Always useful to confirm a program or delivery source is using the standard 1920X1080, of course. -- John

EDIT: Here's an extract from CNET's review (http://reviews.cnet.com/projection-tvs/samsung-hl-r6768w/4505-6484_7-31335745.html) of the Samsung display used for the FIOS effective resolution measurement:
Resolution is a mixed bag, as the Samsung HL-R6768W didn't actually deliver all 1,920 lines of horizontal resolution. However, unlike many HDTVs, the Samsung does process HD accurately, retaining the resolution in the signal.
So, as mentioned earlier, test disc, software, or pattern-generator confirmation of the actual limitations would be useful, as well as FIOS effective resolution measurements with other displays wtih HDNet's patterns.

The Mits model linked above measured ~25% too low by CNET, or ~1440 lines. But even that would be adequate if a STB and/or delivery system was limiting effective resolution to ~1300 lines.

The Mits model linked above measured ~25% too low by CNET, or ~1440 lines. But even that would be adequate if a STB and/or delivery system was limiting effective resolution to ~1300 lines.

I think it's even more complicated than that. To measure the line frequency shouldn't you oversample by at least 2 pixels (Nyquist)?

I think it's even more complicated than that. To measure the line frequency shouldn't you oversample by at least 2 pixels (Nyquist)?
Greetings, zoyd. You might have missed my addition above about your 1000 line reading and whether that equals ~1335 with a square pixel 16X9 display; not sure if that was from HDNet or not. Doesn't seem feasible, BTW, to measure 1335 lines with a 1024-pixel-limited display.

Interesting point about the Nyquist oversampling. That 1440 number was effective resolution (~25% off 1920).

Guess I've assumed HDNet's test patterns are electronically or computer generated. Recall years back speculating here whether it's more useful for testing HD delivery (matching TV camera or telecine 74-MHz HD sampling) to point a camera at test patterns rather than using pattern generators. Using a pattern generator or computer software at home avoids the Nyquist limitation of 74-MHz sampling, about twice that of the highest HD frequency, which boils down to a limiting resolution (http://archive2.avsforum.com/avs-vb/showthread.php?p=5667245&&#post5667245) of ~1700 lines horizontal rez for 1920X1080. Since folks have reported measuring ~1920 lines from HDNet in the past, it seems they're not using a TV-camera-sampled source. (Or, on 2nd thought, perhaps you're getting into DLP mirror and wobulation sampling.)-- John

Greetings, zoyd. You might have missed my addition above about your 1000 line reading and whether that equals ~1335 with a square pixel 16X9 display; not sure if that was from HDNet or not. Doesn't seem feasible, BTW, to measure 1335 lines with a 1024-pixel-limited display.

Yes, it was from HDNET and my point was that my set limits me to measuring at most 512 cycles/picture width due to the sampling frequency. So for me the set and not HDNET source/STB decoding/etc... may be the limiting factor.


Interesting point about the Nyquist oversampling. That 1440 number was effective resolution (~25% off 1920).

Guess I've assumed HDNet's test patterns are electronically or computer generated. Recall years back speculating here whether it's more useful for testing HD delivery (matching TV camera or telecine 74-MHz HD sampling) to point a camera at test patterns rather than using pattern generators. Using a pattern generator or computer software at home avoids the Nyquist limitation of 74-MHz sampling, about twice that of the highest HD frequency, which boils down to a limiting resolution (http://archive2.avsforum.com/avs-vb/showthread.php?p=5667245&&#post5667245) of ~1700 lines horizontal rez for 1920X1080. Since folks have reported measuring ~1920 lines from HDNet in the past, it seems they're not using a TV-camera-sampled source. (Or, on 2nd thought, perhaps you're getting into DLP mirror and wobulation sampling.)-- John

Thanks for the pointer back to that advisory committee report and past discussions. I prefer their nomenclature (cycles/spatial dim. for "resolution" and "scanning format" for pixel pitch) So from that should I conclude that the best one could hope for from a static B&W test pattern would be (1638x800) x 0.85 (mpeg decode hit) = 1392x680 (~340 cycles/picture height)? Or do we only apply the mpeg degradation for dynamic images?

edit:

Well, the vertical resolution parth of my conclusion seems to be contradicted by GeekGirl's measurements:
"Vertical resolution (horizontal wedge): 950 = 9.5 (playing) * 100, 750 = 7.5 (pause) * 100"
Although this doesn't agree with overall behavior of the measurements in the technical report which all showed a lower vertical resolution then horizontal resolution. From the report:

Hres=460 (lines=460x2x16/9 =1636)
Vres=400 (lines=400x2=800)

I also found it interesting from that report that color 720p has significantly better vertical resolution than 1080i.

Thanks for the pointer back to that advisory committee report and past discussions. I prefer their nomenclature (cycles/spatial dim. for "resolution" and "scanning format" for pixel pitch) So from that should I conclude that the best one could hope for from a static B&W test pattern would be (1638x800) x 0.85 (mpeg decode hit) = 1392x680 (~340 cycles/picture height)? Or do we only apply the mpeg degradation for dynamic images?
Never did like the cycles/PH, etc. outlined in the ATSC committee's Resolution (http://www.atsc.org/news_information/papers/1995_acats/tsreport.pdf) intro paragraph for its measurements (table 2.3), so that's why I converted it for this table (http://archive.avsforum.com/avs-vb/showthread.php?postid=326565#post326565) oriented to 16X9 HD displays.

It's been a few years since I mulled all this over, but fairly sure you'd have to distinguish between non-sampled test pattern images and those made with a camera (74-MHz sampling). The HDNet wedge patterns seem to be non-sampled and should provide close to ~1920X1080. Recall Gary Merson's review of the first 1080p RPTV, with HDNet via pre-HDLite DirecTV a few years back got that, and he wrote his signal generator then supplied a full 1920X1080 resolution.
edit:

Well, the vertical resolution parth of my conclusion seems to be contradicted by GeekGirl's measurements:
"Vertical resolution (horizontal wedge): 950 = 9.5 (playing) * 100, 750 = 7.5 (pause) * 100"
Although this doesn't agree with overall behavior of the measurements in the technical report which all showed a lower vertical resolution then horizontal resolution. From the report:

Hres=460 (lines=460x2x16/9 =1636)
Vres=400 (lines=400x2=800)
Never pinned it down, but the ATSC-approval measurements may imply using sampled signals as well as interlaced CRTs (for 1080i) in the mid-'90s. The test committee has a series of notes (1--5) under table 2.3 (link just above) qualifying some of the readings including vertical resolution (800 lines static). All static-pattern Vres readings of ~1080 from HDNet obviously don't involve the standard Kell factor loss of ~0.7 X format line count, or the additional vertical filtering of 1080i--smearing lines vertically--that further reduces Vres. (BTW, figure A3 (http://www.ebu.ch/en/technical/trev/trev_308-hdtv.pdf) of a recent European report on 720p/1080i compares expected readings with both the Kell factor and more filtering.) Something to factor in with 1080p display might be how 540p bobbing--using 540-line TV fields to create 1080p frames--may be influencing Vres; it's often used with 1080p displays as Merson's tests/lists (http://www.avsforum.com/avs-vb/showthread.php?p=9178202#post9178202) show.

The loss from MPEG-2 decoding I mentioned in my earlier linked table, I've always assumed, was part of the ~20% loss in Hres the video experts predicted in their resolution 'graph intro, even though it appears their measured loss from 1920 (table 2.3) is closer to 15%. Again, their table 2.3 notes 1-5 fudge it a bit more.

I also found it interesting from that report that color 720p has significantly better vertical resolution than 1080i.
Can't find them now, but have posted a variation of my simplified table (http://archive.avsforum.com/avs-vb/showthread.php?postid=326565#post326565) showing the three measurements with higher 720p values than with 1080i by coloring the three. But they're easy to spot visually. Whether the report's table 2.3 notes 1--5 fudges those values isn't clear.

What's needed IMO are some new independent authoritative re-measurement of test patterns--as well as measured values from various major cable head ends, DBS, C-band dishes, etc. Some spectrum analyzer comparisons of program material instead of test patterns would be interesting, too. Suggested this to the SMPTE but so far no reports of pending tests. -- John

Thanks for the great info, I have been interested in this subject but until recently haven't had time to go poking around for info. So the HDNet patterns shouldn't suffer from any camera sampling/filtering degradation because they are computer generated but doesn't the de-interlace at the panel introduce smearing (vertically)? And if you don't have 1:1 pixel mapping you should throw in the Kell factor also, shouldn't you?

So the HDNet patterns shouldn't suffer from any camera sampling/filtering degradation because they are computer generated but doesn't the de-interlace at the panel introduce smearing (vertically)? And if you don't have 1:1 pixel mapping you should throw in the Kell factor also, shouldn't you?
Sure seems as though HDNet patterns are either computer or produced with pattern generators. AIUI, interlaced 480i or 1080i have additional vertical filtering added at transmission (or earlier) to prevent 'twittering' of finer details when they're displayed partially with one TV field, then the other field 1/60 sec later (on interlaced CRTs). Static test patterns may not need this vertical smearing (filtering) of lines. Progressive displays, of course, either combine the half-frames (fields) into frames--or 'bob' each field separately into frames, losing vertical resolution.

Consultant Michael Robins, in an article (http://broadcastengineering.com/aps/acquisition/broadcasting_hdtv_format/index.html) outlining 720p, points out that the 0.7 X line count (Kell factor) lowering vertical resolution applies to progressive images unless they originate from computers. So, with HDNet's patterns, reportedly measured close to 1080 lines with some 1080p displays, the Kell factor isn't entering. Best I've measured for Vres with my year-2000 9"-gun 64" CRT 1080i RPTV is ~800 lines (using HDNet).

Don't have any data on scaling and 1:1 mapping. But, somewhat aside, it may be that viewing telecined movies on 1024X768 displays delivers most of the resolvable detail present. As quotes and sublinks in this post (http://www.avsforum.com/avs-vb/showthread.php?p=9314235&&#post9314235) point out, 800-1000 lines (motion-video equivalent) maximum effective horizontal resolution is very typical of 1080/24p master tapes used for HD-delivered movies. Whether newer 4k scans downconverted to 1080/24p and used for some HD discs provide far more Hres hasn't been measured yet, although many reports cite 'crisper' images. -- John

I'm not sure the Samsung HL-R6768W is an ideal display for measuring horizontal resolution since it only has 960 horizontal pixels on the chip. Does anyone have any data on whether it can actually achieve an effective resolution of 1920 lines/picture width using the "wobulation" technique?And the other postings after that. Interesting discussion, but the point is that I'm trying to measure the resolution of my Samsung display, not vice versa. As long as the test pattern has better resolution than the "Display Under Test" why is there a problem?

Perhaps the unanswered question is how the "wobulation" works to trick the human eye. Popular Science has an interesting article that shows the technique: http://www.popsci.com/popsci/bown/2004/homeentertainment/article/0,22221,767810,00.html. It's not that technical, but it shows the concept. My thinking is that since the mirror moves at 2x60 Hz, the processor is putting pixels on top of- and adjacent to- each other in subsequent mirror flips. The (native?) resolution should be 960 and the effective resolution somewhere between 960 and 1,920. As nature works in logarithmic ratios (like human eye sensitivity), I would take the geometric mean between the two: sqrt(960 * 1920) = 1,358, which is close to my measurement.

Data repeated below. Multiply by 16/9 or whatever ratio you think applies. I still see 7.5 horizontal, but it's a judgment call (7 to 8, depending on where the lines blur together).

Display: Samsung HL-R6768W (67" DLP), room lighting = low ambient
Source: Motorola QIP6416-2 HD-DVR, Verizon FiOS, 1080i, HDMI interconnect.

Vertical resolution (horizontal wedge): 950 = 9.5 (playing) * 100, 750 = 7.5 (pause) * 100
Horizontal resolution (vertical wedge): 1,333 = 7.5 (pause or playing) * 100 * (16/9)

- Can someone tell me why I can't see the "10" using a YCC 4:4:4 color space, but it's just fine using RGB color space in the STB? Still confused on this.

And the other postings after that. Interesting discussion, but the point is that I'm trying to measure the resolution of my Samsung display, not vice versa. As long as the test pattern has better resolution than the "Display Under Test" why is there a problem?


The raw test pattern has enough resolution but the discussion was geared towards what happens during transmission, i.e. can you expect the line frequency to be maintained by the time it hits your display.


- Can someone tell me why I can't see the "10" using a YCC 4:4:4 color space, but it's just fine using RGB color space in the STB? Still confused on this.

I did comment on this in the 6416 thread, I don't see this behavior with my moto, I can see the "10" in either RGB or YCC settings.

zoyd - Thanks. Missed yesterday's post. I asked here since I wasn't sure if it was an STB problem or something related to a pure color space concern (for this forum).

Perhaps the best method for establishing wobulation-display (or others) maximum effective resolution is using HD test discs, the resolution wedges on Blu-ray discs, pattern generators like the AccuPel, or computer software. Published reviews help. Then less-certain sources, such as HDNet via FIOS or standard-cable systems, can be measured for a maximum. -- John

Just ran across this statement at filmbug.com

"Due to technical reasons having to do with the video equipment, recording technologies, and the 19.2 Mbit/s-limited ATSC channel, some HDTV signals will not reach their nominal resolution. Most notably, 1080i60 is impossible to broadcast without artifacts at this bandwidth using ATSC. Most 1080i broadcast signals actually are filtered to 1440 horizontal samples to allow adequate compression"

If this is the case then the HDNET test pattern will not be adequate for horizontal resolutions > 1440. I've got a 1920 LCD display I can hook-up my moto box to this weekend and I'll try to verify.

Spotted similar comments about a 1440-line limitation almost from day 1 of HD broadcasting. Gets murky as well as tricky IMO: Don't doubt that the ATSC broadcast format of 19.39 Mbps (~17 Mbps video payload (http://archive.avsforum.com/avs-vb/showthread.php?postid=2516871#post2516871)) can't deliver full-motion 1920X1080i with the same effective resolution (http://archive2.avsforum.com/avs-vb/showthread.php?p=5667245&&#post5667245) as this standard-format resolution. But keep in mind that HD's standard 74-MHz sampling (cameras, telecines) requires Nyquist filtering to prevent aliasing, reducing 1920 lines to ~1700 lines effective resolution. To obtain an effective resolution of 1920X1080 matching the format resolution, sampling at ~148 MHz (double) is needed, with downconversion to 1920X1080 in order to boost the limiting resolution (~1700) to ~1920.

The ATSC MPEG-2 codec uses lossy compression so that as motion increases in images fine details are 'tossed out' to achieve a ~17 Mbps payload (or often less). So, prefiltering at some stations may well filter effective resolutions to ~1440 lines, although the broadcast format would still be 1920X1080i. Encoding hardware efficiency varies. Also, widely used HDCAM recorders deliberately limit 1080 resolution to <1440 lines, although tape signals are upscaled to 1920X1080 before broadcasting. The prefiltering of frequencies between 1440 and 1920 eliminates noise and sometimes film grain that makes HDCAM ~140 Mbps bit rate and tape speed possible. Networks now use newer HDCAM-SRs without 1440 limitations, although the earlier HDCAM is still used for production, too.

Test patterns such as HDNet's delivered at 17 Mbps video payload are mostly static images, requiring very little of the full bit rate, so resolution wedges achieving 1920-line effective resolution are possible.

Guess this all relates to calibration and the thread topic by trying to pinpoint HDNet's current maximum test pattern resolution from typical sources (FIOS, standard cable, C-band, DBS, although not D*'s HDLite, or even the few reported OTA stations relaying HDNet). Earlier above, believe I mentioned the typical max HDNet test pattern readings most viewers have been reporting at AVS (~1300 lines), with one claiming ~1920 lines from HDNet with a 1080p LCD RPTV on a smaller cable system, using a SA8300HD STB. -- John

The ATSC MPEG-2 codec uses lossy compression so that as motion increases in images fine details are 'tossed out' to achieve a ~17 Mbps payload (or often less). So, prefiltering at some stations may well filter effective resolutions to ~1440 lines, although the broadcast format would still be 1920X1080i.

I don't think they filter the horizontal information in the way you are thinking. I've noticed this on some of my stream captures of HD stations that are not 5C protected. The format is 1920x1080 with an anamorphic 1440x1080 payload. That way 33% of the image is black leading to a higher compression ratio. I guess the mpeg2 decoder must know to remap the 1440 back to 1920 horizontal pixels.

edit: Did subsequently find that wrapping a smaller anamorphic image within a larger format is done all the time in the dvd world (anamorphic 4:3 displayed as 16:9). The mpeg header carries the image offsets and aspect ratio so that the display can reconstruct the proper image.

I don't think they filter the horizontal information in the way you are thinking. I've noticed this on some of my stream captures of HD stations that are not 5C protected. The format is 1920x1080 with an anamorphic 1440x1080 payload. That way 33% of the image is black leading to a higher compression ratio. I guess the mpeg2 decoder must know to remap the 1440 back to 1920 horizontal pixels.
Hadn't heard that before. Only encountered mention of anamorphic-type compression with Fox's 480i/p, and there believe it was only from the network to stations in anamorphic form. Suggest posting such a finding in the HD programming forum for some of the gurus. -- John

Edit: A bit of Googling suggests this 1440 technique is used in HDV, the prosumer tape format.

Edit: A bit of Googling suggests this 1440 technique is used in HDV, the prosumer tape format.

yes, it allows you to get an hour onto a minidv format tape. I'm going to get some frame grabs of several of the in-the-clear HD channels to see if some are using anamorphic compression or not and also measure the HDNET pattern using a true 1920 display. I have read elsewhere on the forum that the PQ on HDNET movies is not as good when watching the same movie on the premium HD channels, maybe this is the reason. I'll post any results I get to the HDTV forums.

A bit of Googling suggests this 1440 technique is used in HDV, the prosumer tape format.Is that an issue of pre-filtering, or an issue of the sensors only producing a max of 1440 pixels in the 1080i camcorders (specifically Sony)? I do know that the JVC prosumer cameras (being adopted by several stations) have full 720p x1280 resolution onto HDV, and that's roughly the same bitrate as 1080i x 1920.

Is that an issue of pre-filtering, or an issue of the sensors only producing a max of 1440 pixels in the 1080i camcorders (specifically Sony)? I do know that the JVC prosumer cameras (being adopted by several stations) have full 720p x1280 resolution onto HDV, and that's roughly the same bitrate as 1080i x 1920.
Mulling it over a bit more, believe the prosumer HDV format is specified at 1440X1080. Camcorder sensors might be capable of higher resolutions, but tape size and speed require such limits because of the restricted bandwidth. AIUI, a 1440X1080 signal feed to some displays would be automatically upscaled to 1920X1080i/p (or downscaled, as needed). Or, more likely, the HDV playback hardware could perform the upscalling to 1920X1080i.

Sony's prefiltering for it's pro HDCAM hardware is similar in that 1440 is a cutoff resolution (for the tape, not the camera). During production processing or before transmission that 1440X1080 is upscaled to 1920X1080i. Perhaps, to speculate, both HDV and HDCAM are using FIR (finite impulse response) filtering (http://archive.avsforum.com/avs-vb/showthread.php?postid=1423815#post1423815) that averages and samples 'missing' resolutions/frequencies (1440--1920), and these stored samples can then be used to enhance PQ during upscaling to full 1920. Codec engineer dr1394, who wrote that linked post, mentioned ATSC doesn't permit such filtering.

Also, Fox's network-to-station delivery of so-called 'anamorphic' 480i (before their switch to 720p) I mentioned above was meant for expansion to 16X9 480p from 4X3 480i, as I recall. Seems to be an electronic adaption of the optical meaning of anamorphic; that is, using a special lens that horizontally squeezes images while recording them, then a different lens to widen optically compressed images during playback. -- John

The contrast between 1920X1080i measurements made during mid-'90s approval of the ATSC HD formats and readings from HDNet's 1080i test patterns are significant. The reasons aren't entirely clear. The ATSC approval final report appears at the ATSC site (http://www.atsc.org/news_information/papers/1995_acats/tsreport.pdf) and table 2.3 summarizes measurements while the "Resolution" intro paragraph summarizes their approach. As mentioned above, I posted this simplified table (http://archive.avsforum.com/avs-vb/showthread.php?postid=326565#post326565) of table 2.3 data.

Here's what one reviewer, Gary Merson, using HDNet's resolution-wedge patterns to test Toshiba's now discontinued 1080p RPTV for the May/June '03 "The Perfect Vision, wrote:
...While the test transmission clearly showed the 1080 lines of resolution vertically, the broadcast's horizontal resolution fell a tad short. (Resolution is determined by taking the highest number of lines viewable and multiplying it by the picture width--in this case, 1000 lines times 1.777, which equals 1770 pixels or lines.) My test generator confirmed that the few missing lines were likely caused by a limitation of the camera and/or compression and not by the Toshiba display.
Merson used a pre-HDLite (1920X1080 NOT reformatted to 1280X1080) DirecTV receiver. About that time another AVSer measured HDNet's res patterns and concluded (http://archive.avsforum.com/avs-vb/showthread.php?postid=2112611#post2112611) they were computer generated, not from a camera. Earlier above I linked an authoritative article pointing out non-sampled computer-generated images needn't undergo the sharp (0.7 X line count) vertical resolution loss from the Kell factor of sampled (camera, telecine) images. One other member (http://www.avsforum.com/avs-vb/showthread.php?p=8509731&&#post8509731) reported measuring >1900 lines from HDNet with a LCD 1080p via his TWC head end and a 8300HD. Most have posted measuring ~1300 lines maximum effective lines of horizontal resolution from HDNet. Other HDNet readings, such as those planned by zoyd above, would help pin down differences.

The ATSC measurements, presumably using the best-quality HD CRT monitors available at time, were 1638X800 for the static B&W pattern test. Whether these differences with HDNet are just a difference in years, pattern source (computer vs. TV camera), or display hardware, is still unknown. -- John

Mulling it over a bit more, believe the prosumer HDV format is specified at 1440X1080. Camcorder sensors might be capable of higher resolutions, but tape size and speed require such limits because of the restricted bandwidth. I checked some documentation (from Steve Mullen) that I have which confirms what you are saying. The HDV format is limited to1080i with 1440 pixels/line OR 720p with 1280 pixels/line. I had come to my conclusion that it was limited by the cameras based on the first 3 chip Sony prosumer camcorder (HDR-FX1) which had, I believe, 1080 x 960 sensors. By using a green pixel shift, these were able to produce a luminance signal with 1080 x 1440 pixels. Hence, my association of 1440 with the sensors, not the standards.

Good discussion, though.

Saturday, June 23rd, at 6:30 am ET
http://www.hd.net/program_search_results.html?keyword=test&whattosearch=title

Sunday or Tuesday mornings were slated for airings previously. To locate upcoming changes go to: hd.net, select schedules, then search programming, then HDNet, then use TEST as a TITLE search word ("HDNet test patterns"). -- John

Has anyone tried to use the HDnet Test Pattern for white-balance calibration or gamma measurement? — specifically, the "resolution pattern" at the 4min (remaining) mark? I called HDnet and talked to one of their techies, who assured me that the grayscale blocks at the bottom of that pattern go from 0% to 100% in 10% steps. Any pitfalls in using this pattern to set color temp and to read/compute luminance and gamma? In particular, is the APL of this pattern too high to get accurate readings on a plasma? The gray "background" of the majority of this pattern is identical to the 60% gray block. And are the steps accurate?

I've used this pattern to dial in the white balance using the User Mode controls of my Panny TH-50PH9UK, and to my eye, it took the panel's color accuracy from obviously wrong to extremely sweet, especially judging from sports uniforms, the kind of things I've seen live enough times to know what color they should be. I get screwy numbers when trying to measure gamma, though, which makes me skeptical of the accuracy of the grayscale steps, though this could have been pilot error as well.

Just curious what the experts think about this particular pattern for this particular application.

Thanks,
Jim S.

P.S. I should add that I'm using a Spyder2 and HCFR to do the calibration(s).

Saturday, June 23rd, at 6:30 am ET http://www.hd.net/program_search_results.html?keyword=test&whattosearch=title Sunday or Tuesday mornings were slated for airings previously. To locate upcoming changes go to: hd.net, select schedules, then search programming, then HDNet, then use TEST as a TITLE search word ("HDNet test patterns"). -- JohnFor Verizon FiOS, the program guide shows up as "Off Air" - transmitter maintenance. No hint of test patterns whatsoever.

For Verizon FiOS, the program guide shows up as "Off Air" - transmitter maintenance. No hint of test patterns whatsoever.I have found that HDNet is not too hot on getting programming updates to the data service providers (TVGuide & Tribune) that all the cable/satellite providers use. Titan simply lists HDProgramming for Saturday morning, but TW, here in Rochester, lists the test patterns for Sat AM OK. It will probably show up for you in a day to two.

Probably not. It's been a few weeks and "Off Air" is the only description shown. Program times are OK. A TiVo owner on Broadband Reports said that his program guide listed the title as "Test Patterns", but the description as "Vintage episodes of Canada's favorite game shows." http://www.dslreports.com/forum/remark,18411359

For Verizon FiOS, the program guide shows up as "Off Air" - transmitter maintenance. No hint of test patterns whatsoever.
Interesting. Thanks. Often my TWC guide, for the earlier SUnday/Tuesday HDNet test pattern showings, wasn't accurate until about one day before the showings. If Verizon's FIOS doesn't deliver the Saturday June 23 6:30 am patterns (HDNet search link above).... ! -- John

Has anyone tried to use the HDnet Test Pattern for white-balance calibration or gamma measurement? — specifically, the "resolution pattern" at the 4min (remaining) mark? I called HDnet and talked to one of their techies, who assured me that the grayscale blocks at the bottom of that pattern go from 0% to 100% in 10% steps. Any pitfalls in using this pattern to set color temp and to read/compute luminance and gamma? In particular, is the APL of this pattern too high to get accurate readings on a plasma? The gray "background" of the majority of this pattern is identical to the 60% gray block. And are the steps accurate?

I've used this pattern to dial in the white balance using the User Mode controls of my Panny TH-50PH9UK, and to my eye, it took the panel's color accuracy from obviously wrong to extremely sweet, especially judging from sports uniforms, the kind of things I've seen live enough times to know what color they should be. I get screwy numbers when trying to measure gamma, though, which makes me skeptical of the accuracy of the grayscale steps, though this could have been pilot error as well.

Just curious what the experts think about this particular pattern for this particular application.

Thanks,
Jim S.

P.S. I should add that I'm using a Spyder2 and HCFR to do the calibration(s).
Yes, used the pluge pattern inset into the resolution-wedge screen a few years ago for checking my 64" CRT RPTV. As I recall, using a few live 1080i sports programs, sourced in bright sunlight, I then slightly readjusted brightness/contrast and even tint/color for the most realistic flesh tones and other colors. Not really a calibration expert, but since shadow detail was too low for the live 1080i I adjusted user controls until images looked 'normal'. Most programming has appeared normal since, and when color is off (rarely) I assume something's misadjusted by the program source, not my display. There's never been a huge difference between HDNet pluge settings and what appears better to my eyes. (Not a color-TV neophyte, having built and adjusted three color TVs from kits, and adjusted/repaired an Advent 1000 CRT FP for about 21 years.)

About the time I measured 1280-line (http://www.avsforum.com/avs-vb/showthread.php?postid=5175424#post5175424) effective resolution from HDNet's resolution wedges (and 1335 later with another cable system and different STB), a local ISFer measured and posted a 1290-line effective resolution using a 1366X768 plasma like yours. Some time later a local Ruby 1080p FP owner measured ~1335 lines (http://www.avsforum.com/avs-vb/showthread.php?p=8865051#post8865051) from TWC. Some other HDNet pattern users, besides this one who claims seeing >1900 lines (http://www.avsforum.com/avs-vb/showthread.php?p=8509731&&#post8509731) from a smaller Calif. cable system, may also be getting roughly full resolution. If so, suspect the measurement with a 1366X768 display would show clearly resolvable detail out to ~1366 lines (~7.67 on the wedges), indicating a higher-rez display would show more.

That's with test patterns, of course, while programming, going by AVS and other estimates posted for years, may be limited to ~1450 lines equivalent maximum effective horizontal resolution with good HD sources, but only 800--1000 lines (http://www.avsforum.com/avs-vb/showthread.php?p=9314235&&#post9314235) effective resolution from non-HD-disc movie sources. -- John

Yes, used the pluge pattern inset into the resolution-wedge screen a few years ago for checking my 64" CRT RPTV ...
Thanks John. I'm curious to hear if someone has used the 11 blocks at the bottom of that pattern to measure the luminosity curve and derive a gamma measurement.

Thanks John. I'm curious to hear if someone has used the 11 blocks at the bottom of that pattern to measure the luminosity curve and derive a gamma measurement.

I'll take a look at it this weekend (also the resolution using a 1920x1080 display), just haven't gotten around to it yet.

I can think of a few issues with trying to use the HDNet blocks at the bottom to measure the lumiosity:
1) Block may be smaller than the viewing angle of the measurement device - so you may also be measuring some adjacent areas as well.
2) The number in the middle of the block will add some error to the measurement
3) CRT sets and all RRPTVs have some uniformity issues - so those may also impact measurements.

Hi Dave. Good point on #1. As for #2, I'm talking about the pattern later on in the broadcast (http://www.avsforum.com/avs-vb/showthread.php?p=6664456&&#post6664456) which doesn't have the numbers in the blocks. And as for #3, I've got a plasma, so that doesn't apply to me specifically, but definitely applies to owners of those other display types. Thanks! -- JS

Hi Dave. Good point on #1. As for #2, I'm talking about the pattern later on in the broadcast (http://www.avsforum.com/avs-vb/showthread.php?p=6664456&&#post6664456) which doesn't have the numbers in the blocks. And as for #3, I've got a plasma, so that doesn't apply to me specifically, but definitely applies to owners of those other display types. Thanks! -- JSGotcha - I'm used to using the first ones (with the numbers) that I forgot about these.

I took some measurements this morning and results are below. Unfortunately the LCD display I used to test resolution would not accept a 1080i input (only 720p) so even though it has a native resolution of 1900x1200 the test pattern resolution measurement is inconclusive. I measured vertical resolution at 720 (as expected) and horizontal resolution at 680 x 1.78 = 1200 lines for 16x9 display. This is a bit lower than expected (1280) but probably within the accuracy of this method.

The gray scale was measured using the patches shown during the last test pattern using a spot meter (i1pro) in contact with my display. I compared the HDnet patterns from the moto6416 box via HDMI input to the getgray DVD patterns via the same input.

Correlated color temperature of the HDnet patterns agrees within the measurement scatter so these patterns can definitely be used for CCT calibration. Solid line=HDnet, dotted line=getgray

http://i64.photobucket.com/albums/h173/prairie_2006/hdnet_CCT.png

For gamma measurements I set the contrast so that the 100% HDnet pattern was the same luminance as the 100% getgray pattern. Overall, gamma was lower using HDnet patterns compared to the getgray patterns.

http://i64.photobucket.com/albums/h173/prairie_2006/hdnet_gamma.png

I can get the gamma responses to agree if I shift the HDnet stimulus scale by a flat 3.4%

http://i64.photobucket.com/albums/h173/prairie_2006/hdnet_gamma2.png

I see three possibilities for this difference:

1. The HDnet patterns have a 3.4% scale shift (i.e. 10% is really 13.4%)
2. The HDnet patterns use a slightly different gamma encoding function compared to the getgray DVD.
3. Difference in mpeg decoding between the dvd player and the moto box.

There is no way I know of to tell the difference between these possibilities at the user end.

The color patch measurements were interesting showing a significantly smaller gamut. Getgray results on left, HDnet on right. The reference gamut shown is Rec709, the HDnet gamut is closer to a SMPTE-C gamut. The green luminance as a percent of white (lightness) was also much lower (-36%) than what it should be.

http://i64.photobucket.com/albums/h173/prairie_2006/hdnet_color.png

Great series of measurements, zoyd. Can't follow the 720p-only display input problem though. Reads like it might be a computer-type display (1200 rows) versus a consumer 1080p LCD display, so requires a progressive input? The mystery remains, with AFAIK, only one FIOS/HDNet/STB 1920X1080i reading of ~1333 lines max horiz. rez by GeekGirl above. -- John

Reads like it might be a computer-type display (1200 rows) versus a consumer 1080p LCD display, so requires a progressive input?

correct.

The mystery remains, with AFAIK, only one FIOS/HDNet/STB 1920X1080i reading of ~1333 lines max horiz. rez by GeekGirl above. -- JohnAs a refresh (pun intended), that's an eyeball measurement on a native 960 H pixel display (DLP mirror "wobulation" -> 960 x 1080). I should probably throw in something for tolerance - I can visually resolve down to about 0.5 steps, so take 1/2 of that.

Horizontal resolution (vertical wedge): 1,333 = 7.5 (+/- 0.25) * 100 * (16/9)
1,333 +/-44 = 1,288 to 1,377 lines

Any channels still broadcasting these patterns?

^^^
Hdnet

What time? I don't see it on their schedule

Edit: Found it. January 12th, 2008 at 6:30 am EST for 10 minutes

I'm looking for advice as to how to use HD Net test pattern's color bars to set "color" and "tint". I have the THX Optimizer glasses (came with the THX Optimizer disk from THX). Here are the glasses http://costore.com/thx/productenlarged.asp?peid=87&pid=930793

Can these be used with the color patterns on HD Net's test pattern to calibrate both color and tint? If so, what am I looking for when dialing in "color" and what am I looking for when dialing in "tint"?


Thanks

I'm looking for advice as to how to use HD Net test pattern's color bars to set "color" and "tint". I have the THX Optimizer glasses (came with the THX Optimizer disk from THX). Here are the glasses http://costore.com/thx/productenlarged.asp?peid=87&pid=930793

Can these be used with the color patterns on HD Net's test pattern to calibrate both color and tint? If so, what am I looking for when dialing in "color" and what am I looking for when dialing in "tint"?

ThanksUsefulness of the color bars in HDNet test patterns is limited because they are not "split" color bars.

I'm looking for advice as to how to use HD Net test pattern's color bars to set "color" and "tint". I have the THX Optimizer glasses (came with the THX Optimizer disk from THX). Here are the glasses http://costore.com/thx/productenlarged.asp?peid=87&pid=930793

Can these be used with the color patterns on HD Net's test pattern to calibrate both color and tint? If so, what am I looking for when dialing in "color" and what am I looking for when dialing in "tint"?

The 4th post in this thread has a link to a summary of test pattern use. I've DVRed the patterns and (rarely) borrow the blue filter with my Avia test DVD to ballpark tint/color with HDNet. The setting involves your HDNet source and STB channel, so tailoring user controls to specific programs may be necessary. And if your source in downrezzing HDNet, say from 1920X1080i to 1280X1080i, the resolution tests outlined earlier above may not apply: (displays >1280 horizontally). -- John

HDNet has disappeared from the Verizon FiOS IMG. It's not on the web site, so it's time to let HDNEt know about it. Time for Action! I just sent an email to: viewer@hd.netHello,

I own a home theater owner and have used your HDNet Test Patterns since HDNet started broadcasting them. I record them to my HD DVR and have come to depend on them as one of my "standards". Your HDNet Test Pattern broadcast has recently been dropped from your schedule. Can you please bring it back?

HDNet was founded on the promise of the very best quality video and audio programming. Not having this program available goes against this promise. I will be very disappointed if this program does not return and will no longer consider HDNet as the high quality channel it once was.

An earlier listing:
Sat, Mar 8 - 6:30 AM ET 3:30 AM PT hdnet Test Patterns
Wonder how your home theatre is doing? Wish you had test patterns to help set it up? Well, hdnet is here to help. This short program will help you get the most out of your home theatre setup by providing you with the same professional test patterns hdnet uses to set their gear.

Please put HDNet Test Patterns back! Any time of day is fine, I will record it. Thanks!

http://www.smartcalibration.com/hdnetpatterns.html

I don't see this on my guide (FIOS). There is regular programming shown on every Tuesday at 8am.

It is "off the air" on Saturday, 11/15 at 10am.

Same thing?

^^^
10am saturday is when it is on. time warners guide says HDNet Test Patterns. i recorded it last saturday.

The color patch measurements were interesting showing a significantly smaller gamut. Getgray results on left, HDnet on right. The reference gamut shown is Rec709, the HDnet gamut is closer to a SMPTE-C gamut. The green luminance as a percent of white (lightness) was also much lower (-36%) than what it should be.

http://i64.photobucket.com/albums/h173/prairie_2006/hdnet_color.png

I'm noticing the same thing, especially with the green luminance being much lower probably due to Zoyd's observation of HDNET's smaller gamut. Cyan and yellow are also noticably lower.

Has anyone else noticed this? Thanks in advance.