THE SONY SERVICE CODES - Articles, Comments, Discoveries - Page 12 - AVS Forum
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post #331 of 2973 Old 07-26-2005, 02:41 PM
 
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It's great now because i can clearly look at a dvd transfer and see any flaws in it with these enhancements off.

like on the fifth element superbit edition, picture was much sharper now but EE was evident more clearly now.

This way the tv won't add any EE and get it from the dvd instead.To compensate for 480i and lower rees sources that needed sharpening i left sharpness in the middle and put SYSM at 1. for good material like dvd 480p and above a setting of SYSM 3 looks best.

Thank you for your discoveries in making my day better with my sony
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post #332 of 2973 Old 07-26-2005, 06:46 PM
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KenTech,

Thanks so much for the info in this thread. I bought a brand new Sony KV24fs120 for my bedroom on closeout at Walmart for $160 (an incredibly low price) last month and, naturally, it had some of the very irritating geometry problems associated with this set and commented on ad nauseum at the Circuit City website. Otherwise, the set was fantastic in every way, and there was no way I was going to return it for the low price I paid.

Until yesterday, I did not even know what a "service menu" was. But last night I made adjustments to the TRAP, PAMP, UPIN, and LPIN settings in both the 4:3 and 16:9 modes and now the geometry problems are probably 95% corrected. Thanks for the clear instructions, without which I would never have attempted these changes, especially since I don't feel like purchasing the service manual for this set. The only keying difference in your general instructions was that the KV24FS120 writes changes merely by hitting the mute button (rather than mute - enter).

I have a US Digital HDTV set top box for receiving over-the-air HDTV signals. I set it to 480i and watch digital programs in the 16:9 mode, which squeezes the 480 lines on the 24" Sony from 14 inches vertically to about 10.5 inches. The resultant increase in picture intensity is amazing, and to my eyes much closer to high definition than standard definition. Prior to last night's adjustments, however, viewing in 16:9 intensified the geometry problems, which are now a thing of the past thanks to your invaluable instructions.

Hope I did not distract too much from your more technical posts. Just felt like I had to say "Thanks!!!"
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post #333 of 2973 Old 07-27-2005, 01:50 PM - Thread Starter
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Quote:
Originally Posted by BTT View Post

Thanks for the clear instructions, without which I would never have attempted these changes, especially since I don't feel like purchasing the service manual for this set. The only keying difference in your general instructions was that the KV24FS120 writes changes merely by hitting the mute button (rather than mute - enter).

You're very, very welcome! I'm quite boggled that what has been posted here in the way of *specific* instructions were of value to you. Who knew they would apply to your set, too? Power to the Paying Customer!

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post #334 of 2973 Old 08-01-2005, 12:35 PM
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Just wanted to let everyone know that the green spot in the corner of my TV has improved slightly over the last week. Either that, or I'm just getting used to it. Either way, it's good news for me.

-Reagan

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post #335 of 2973 Old 08-03-2005, 05:00 PM
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unplug your tv andplug it back in

I had this happen to me and the green spot went away.

Fixes it for me everytime.
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post #336 of 2973 Old 08-03-2005, 07:55 PM
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I had a green smear on my Sony once. I freaked out! I thought it was permanent!

The first thing to do is remove the cause. It could be a poorly shielded speaker. In my case, it was a desktop decorative gadget with a strong magnet inside. I casually put the gadget on top of the TV not thinking about the magnetic effect!After removing the cause of the problem, I turned the TV off and on at intervals for a few minutes. The click sound you hear when the TV turns on is degaussing (demagnetizing) the tube. This solved most of the problem. It went away completely after 2 or 3 days.
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post #337 of 2973 Old 08-05-2005, 12:14 AM
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I just picked up a 34XS955 and it has some pincushion distortion and convergence issues. Its just a couple of days old, and I was curious if I called Sony, they could send someone out to fix this in home? This is a noob question, but I am a noob and don't feel comfortable messing around in the service menu quite yet.

It seems Sony should do this under warranty right? Circuit City (where I got it from) doesn't sell it anymore, so an exchange isn't an option.

Thanks
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post #338 of 2973 Old 08-05-2005, 12:59 AM
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I'd like to thank everyone in this thread. I got a 30hs420 about 10 days ago. After reading the thread several times I final went into the SM and am able to change values and such and I have my defaults recorded. I visually adjust my whites with the g & b drvs, but the cuts offs is a little confusing. I went with one of the procedures later in the thread in calculating some of the cut offs where you drive to a yellow. Anyway I seem to be driving towards Kens values so I just threw in his numbers on drvs, cutoffs and the gain. Everything seems pretty good. With Vivid I put Kens P4 image processing values and some of the noise seems to have gone. Standard seems to have the most detail and I use that for TV. Movie and Pro I might switch to for upscaling 1080i DVDs. I may try and figure where Std is getting some of that extra detail and put it in Pro. Although all my modes are converging to be very similar. I leave everything in Neutral color. I'm pretty impressed so far. The strong fleshy tomes are gone. My Gamma pic from Avia shows Std & Movie to be 2.2 and Pro looks to be more like 2.0 and Vivid 1.9. My Gamm for Pro is default 0. Is there some way to boost Pro gamma to something more like 2.2? Thks
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post #339 of 2973 Old 08-05-2005, 11:00 AM
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Quote:
Originally Posted by ramuman View Post

I just picked up a 34XS955 and it has some pincushion distortion and convergence issues. Its just a couple of days old, and I was curious if I called Sony, they could send someone out to fix this in home? This is a noob question, but I am a noob and don't feel comfortable messing around in the service menu quite yet.

It seems Sony should do this under warranty right? Circuit City (where I got it from) doesn't sell it anymore, so an exchange isn't an option.

Thanks

I would definitely call either Sony or CC. I'm not sure which would be the correct one to call first. Let them take their best shot at it before trying it yourself. They owe it to you to correct such problems so early in the game.

Good Luck!
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post #340 of 2973 Old 08-06-2005, 01:27 PM - Thread Starter
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Quote:
Originally Posted by Hef View Post

My Gamma pic from Avia shows Std & Movie to be 2.2 and Pro looks to be more like 2.0 and Vivid 1.9. My Gamm for Pro is default 0. Is there some way to boost Pro gamma to something more like 2.2?

Trouble is, the factory settings for Standard and Vivid (and a bit with Movie) invoke a *dynamic-contrast* feature in the set, controlled by the settings for 2170P-4/BLK and the following three codes: DCTR (dynamic contrast ?), APED, and DSBO (dynamic sub-brightness offset?) BLK is a combo preset for those next three. Any picture mode that sets BLK at 0 turns OFF any dynamic-contrast activity: Pro on all inputs; Movie on all but a few 480i inputs plus ATSC (tuner) 1080i and 720p; and Standard and Vivid on all inputs. So in Pro mode, your black-level settings (SBRT) and xDRV and xCUT settings are seen as you have set them, and gamma is as you have set. On the other picture modes, the wildcard of dynamic-contrast affects both contrast/brightness and apparent gamma based on the video content.

Gamma settings for GAMM=0 (GAMx = 0) *are* max; on my 36XS955 it is about 2.45 in Pro mode. When I change the three GAMx settings to 3, I get a measured display gamma of about 2.2. I have made sure that dynamic-contrast effects are not working *anywhere,* as I don't want the TV making decisions like that based on the video material. I know "Dynamic Picture Control" serves some purposes for unsophisticated viewers and store demo, but it's not to my liking at all.

Bottom line: Do not trust the results of color, brightness, or gamma tests in anything but Pro mode out-of-the-box. (And caution: your black-level settings, SBRT or the Brightness slider, greatly affect the measurement of gamma. Make sure you have set it correctly in low room lighting.)

Of course, as I have, you can re-program the three other modes to be anything you wish. It takes a long time to go to all of the relevant settings for each mode and change them, but I believe it's worth it. (See article #05 - Customizing Picture Modes, in this thread.) I supposed one could leave one of the modes as-is for uncritical bright-afternoon viewing of kids programs or football, which is what may be intended by Sony. But I have never regretted making Pro and Movie *exactly* alike, then altering gamma for Movie to 2.2 (GAMM=1 and GAMx=3). I use that reduced gamma a lot for dark HD programming and some SD material where it's warranted. (CSI/Miami, Lost come to mind.) If it looks better in Movie mode, that's what I use instead of squinting at the shadows!

Glad you're being successful in improving your set, Hef! It will leave you feeling like you have more control, and you will get it to work like *you* wish it to.

KenTech
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post #341 of 2973 Old 08-06-2005, 01:38 PM - Thread Starter
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Quote:
Originally Posted by ramuman View Post

Its just a couple of days old, and I was curious if I called Sony, they could send someone out to fix this in home?

Right. Your *service* warranty lasts for 90 days. As justsc said, you have every right to expect reasonably minimal defects out of the box (although *none* is hoping for too much). You could wait a little longer for the set to "settle in" before calling a service tech, maybe a month or two, but I have no proof that significant changes occur during that time -- especially with geometry and convergence.

Tip: Instead of calling any Sony national 800-number, you might mosey over to a high-endish dealership for Sony, be friendly, and ask them for a service-shop referral. Then call the shop directly. You are likely going to get a more-sympathetic response to your wishes from a local person than from a Sony-service call center! I had *no* problem with this 7 days before the warranty expired, and he was able to correct a global up/down red shift. Then he explained the nightmare of doing small local corrections that might throw off the otherwise-excellent convergence elsewhere. (It all interacts; I know this from experience.) Having his superior wisdom in the house for a while was a definite benefit!

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post #342 of 2973 Old 08-06-2005, 02:38 PM
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Does anyone know how to correct overscan for 1080i sources only, without it affecting 480p? I have a Sony 30xs955.
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post #343 of 2973 Old 08-06-2005, 08:39 PM
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Ken,

FWIW, I just ran across an updated version of the PNG gamma tutorial posted previously which gives average CRT gamma as 2.2 instead of 2.5.

http://www.libpng.org/pub/png/spec/1...aAppendix.html

Here's the previous version of the document for comparison which assumed a 2.5 CRT gamma. Note that the "viewing gamma" (now referred to as the "end-to-end exponent") for a dim surround was also changed accordingly from 1.25 to 1.14.

The source of these changes may have been the HP CRT survey mentioned in this document.

These documents are geared a bit more toward web applications though. So I kinda wonder if they might have gotten a little different average gamma readings if they'd sampled home theater CRTs instead of computer monitors.

More discussion re gamma & DVDs: http://www.avsforum.com/avs-vb/showt...71#post5999871

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post #344 of 2973 Old 08-09-2005, 11:26 AM
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Re 2.2 vs. 2.5... I did a test to see what difference black level makes in the gamma reading on my 34XBR800 using the patterns posted earlier in the thread.

If I use RGB=0 as my black reference, then I get a gamma reading of about 2.25.

If I use RGB=16 as my black reference, then I get a gamma reading much closer to 2.5.

Perhaps that's the source of some of the confusion re the average CRT gamma. Maybe the video guys are adjusting for something approximating RGB=16, and the Internet guys are adjusting for RGB=0. I think gamma patterns like the ones posted here are really intended for use with a full 0-255 RGB "computer palette" though, rather than a 16-235 "video palette"* (with black level adjusted lower). And my guess is that HP did their survey using RGB=0 as well, and that's how they arrived at an average CRT gamma of ~2.2.

Ken,

Do you remember which way your black level was set when you took your gamma readings? Was it set for RGB=16, or RGB=0?

*I put "computer palette" and "video palette" in quotes because digital video input devices may use either a 16-235 RGB palette, or a 0-255 RGB palette.

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post #345 of 2973 Old 08-09-2005, 01:46 PM - Thread Starter
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Quote:
Originally Posted by ADU View Post

Do you remember which way your black level was set when you took your gamma readings? Was it set for RGB=16 (~7.5 IRE), or RGB=0?

You are confusing the concept of black level as input-standard (a voltage representing 0 or 7.5 IRE) with black level as observed (set, say, with a PLUGE pattern). As observed, black is black if properly adjusted no matter what the input is that represents black. In my case, I see a slight screen glow for *absolute* digital black, which is an orthodox result from a DVD PLUGE calibration using *my* player. One can confirm with the "digital black" screens on, say, the DVE DVD.

I did PLUGE only once for my DVD input, since there is little variation among high-quality DVDs, and that was with Brightness at 31. That is generally satisfactory.

For broadcast video, tapes, etc., black level is empirical: I adjust Brightness until the observed black level appears correct -- relatively easy. Brightness = 31 is only a starting point! I don't care if the source-black is 0, 7.5, or any other bizarre IRE level (some cable channels are way off!), it ends up *looking* black.

It would be best to refer to screen brightness as percent-white, not IRE. My measurement of gamma occurred after confirming a perfect black level in low-level evening room lighting.

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post #346 of 2973 Old 08-09-2005, 03:59 PM
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You are confusing the concept of black level as input-standard (a voltage representing 0 or 7.5 IRE) with black level as observed (set, say, with a PLUGE pattern).

Or perhaps not stating my question very well. What I meant to say was-- what color black were you using as your reference when setting the Brightness/black level on your TV prior to taking your gamma readings, RGB=0 or RGB=16? It's probably irrelevant though since I don't have enough info about the rest of your setup to put that information into a useful context, so just forget I asked.

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post #347 of 2973 Old 08-09-2005, 04:04 PM
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One thing with that very thick piece of glass on the face of the tube, black levels suffer significantly with bright image content. This is one main reason Ken sees a slight glow with his black level setting. Anything lower and you have major losses in black detail.

The Pluge pattern can be used to set black level, but you should check it with a high APL pattern too.

I agree that there are many video sources that can be improved by tweaking Picture and Brightness, DVD, SD broadcast and HD.

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post #348 of 2973 Old 08-09-2005, 04:55 PM - Thread Starter
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Quote:
Originally Posted by GlenC View Post

One thing with that very thick piece of glass on the face of the tube, black levels suffer significantly with bright image content. This is one main reason Ken sees a slight glow with his black level setting.

How are these two statements related? The slight glow is generated by the tube, easy to see, since I have a 4:3 tube, and the boundary of a 16:9 display is clearly visible if there is a glow.

The thick, dark glass reduced the brightness of all light emission evenly, bright and dim. Picture and Brightness settings compensate for it completely. That the glass is dyed dark reduces the effect of room light on the tube face, making the shadow detail much clearer. (Room light has to pass thru the glass *twice.*)

If you set "black" to absolute black (no light emitted), the darkest shadow colors are too saturated and shadow detail is lost. The "toe" of the emission curve is also polluted by room light. I have experimentally adjusted black levels up and down with great sources (usually DVDs), and the best results are with video-black for the source chosen set *slightly* above absolute black for the CRT. The resulting picture qiality proves the point: anything else doesn't look right.

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post #349 of 2973 Old 08-09-2005, 06:07 PM
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I agree... sort of. In general though, I don't think you should be able to see a glow from a black screen in your normal ambient lighting. (Unless you have no choice but to use Brightness to compensate for other issues in the CRT's design or adjustment.)

FWIW, if you set your black level with your normal ambient viewing light on, and just try to dial down your reference black till you achieve what appears to your eyes to be a perfect match with a 0-voltage area of the screen* (but no lower), then you should be leaving just enough room for the toe**... something you can probably verify by turning all ambient light off, and then confirming there's a slight glow from the screen.

If there's a detectable glow on a black screen when your ambient light is on, then darker scenes may appear to ride on a pedestal of dark grey.

If colors look excessively saturated with black set this way, then your gamma (or contrast) may need some further tweaking. Just my 2c.

*...or using whatever method your calibration DVD recommends.
**...if there is one.

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post #350 of 2973 Old 08-09-2005, 06:46 PM - Thread Starter
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Quote:
Originally Posted by ADU View Post

If I use RGB=0 as my black reference, then I get a gamma reading of about 2.25. If I use RGB=16 as my black reference, then I get a gamma reading much closer to 2.5.

This illustrates the difficulty of measuring gamma with any type of screen pattern. The usual pattern juxtaposes two areas: (1) a specific composite "gray" that is composed of black and white in some pattern, say alternating black and white scan lines. (If black is truly black, that is a (linear) 50% brightness relative to the white level). And (2) a real solid gray of calculated density such that for a given gamma, say 2.2, the brightness of the solid gray appears exactly the same (average) brightness as the b/w composite gray. You blur your eyes, if that helps. Raising the black level with the Brightness control screws up the relationship between those two "gray" areas, giving a false reading.

In actual fact, Brightness (black level) setting has *no* effect on real gamma: In practice, the measured brightness response of any CRT display is composed of a fixed-brightness pedestal plus a curve relating video input to additional screen brightness. Changing the pedestal height (adding a screen glow or eliminating it or making it negative) does not change the power factor of the curve: the gamma. But measuring this would require a photometer aimed at the screen and a variable, calibrated video-level generator as input. Then you could draw the graph, separate the curve from the pedestal, and determine the exponent of the curve. *That* would be measureing gamma! But we're stuck with using patterns, and so one has to be careful to calibrate screen-black to a digital-black signal, and the whole measurement must be done in a very dark room. That is how I estimated the inherent max gamma of my set for GAMM=0 at 2.45. It amounts to an interesting tidbit, and one can set other gammas with the GAMx codes (3 yields about 2.2). But I yearn for a true Gamma Control, and *that* would be correctly labeled "Contrast." I set gamma to suit the program material, and the max setting is usually the best, especially with DVDs and SD broadcast. But then there are those few super-contrasty broadcasts that lose a lot in the shadows. Lower gamma to the rescue!

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post #351 of 2973 Old 08-09-2005, 06:53 PM
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I have a 34XS955 and I've been monkeying around for the past few weeks in the service menu trying to make my TV look better and I have a question and a few problems that I can't seem to get rid of.

My question is this: Is it better to make adjustments, both geometry and picture, in the 2170P and 2170D groups, or the MID5 group?

Now, to my problems:
1) I have a stripe that runs down the center of the screen that is slightly brighter then the rest of the screen. It's hard to see unless there is a light, fairly uniform background, but on pictures of the sky or anything like that, it's really noticeable. I can't see any way to smooth that out.

2) The left side of the screen shows a distortion about 1/4 of the way from the edge that looks like it's being pinched together there. It makes horizontally panning images look wavy. I originally thought that it was an issue with the horizontal linearity, but I can't seem to get it smoothed out.

Well, thanks in advance for any assistance anyone can render.
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post #352 of 2973 Old 08-09-2005, 07:02 PM - Thread Starter
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Quote:
Originally Posted by ADU View Post

If colors look excessively saturated with black set this way, then your gamma (or contrast) may need some further tweaking.

Or raises the bigger problem of broadcast quality control. The ideal is that correct shadows and correct dark-color should occur with the same black-level adjustment.

But I regularly encounter video that doesn't fit that description: Colors are oversaturated in shadows even though the shadow brightness (black level) is fairly high! Everybody in the scene has orange-red colors under their chins and noses and behind their ears, but there is no real black in the picture -- what to do? I diddle Brightness for a good compromise, then enjoy the show.

I regularly see meticulously set up video from the big three networks on their HD programming -- set black level to a real black, and the results are just about perfect. But there's a lot that doesn't conform.

My TV is calibrated for Brightness = 31 and Color = 31 to be a best-possible average. For DVDs it's perfect. Then I watch an ABC program called Brat Camp and can't get black levels right until I jack Brightness to 36. Color is fine. Later, the local ABC news requires me to set Brightness back to 31.

On a Friday evening I watch some PBS half-hour news programs, and I have to crank Brightness down to 25 and Color to (get this) 21 for a reasonable picture! Why is PBS transmitting 150% chroma?? Who is minding the store? Am I worried about gamma? Hah!

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post #353 of 2973 Old 08-09-2005, 07:48 PM
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Quote:
Originally Posted by KenTech View Post

This illustrates the difficulty of measuring gamma with any type of screen pattern. The usual pattern juxtaposes two areas: (1) a specific composite "gray" that is composed of black and white in some pattern, say alternating black and white scan lines. (If black is truly black, that is a (linear) 50% brightness relative to the white level). And (2) a real solid gray of calculated density such that for a given gamma, say 2.2, the brightness of the solid gray appears exactly the same (average) brightness as the b/w composite gray. You blur your eyes, if that helps. Raising the black level with the Brightness control screws up the relationship between those two "gray" areas, giving a false reading.

That might explain some of the difference in readings we're getting, because I set my black level with the ambient light on as described in my last post, prior to taking my measurements. If I had set the black level lower in an attempt to match the CRT's "absolute black" then it's quite possible I might have gotten a little higher reading than 2.25... but (as I rethink it) not necessarily a more accurate one.

You're more likely to get an incorrect reading from these gamma patterns if your Brightness is set too low than if it's set too high. So for the time being, I'll still stand by my 2.25 as the more accurate measurement of my CRT's true gamma.

If Brightness/black level is set so low that the darkest RGB values (ie, the black lines) in the gamma pattern become truncated (...something which might occur if you're using RGB=16* as your black reference, and/or trying to adjust black level in total darkness...), then the relationships between the swatches and B&W lines breaks down and the gamma reading becomes unreliable.

If Brightness/black level is set higher, then the swatches and lines should still maintain their brightness relationships and give you a pretty accurate reading, because they are all increased in brightness by the same amount.

*Just to clarify, I'm not trying to advocate here that people should use RGB=0 for their regular video setup, instead of RGB=16. Whether you use RGB=16 or RGB=0 (or some other black reference) in setting up your display for proper viewing depends entirely on the video source. My point here is that using RGB=16 as your black reference may simply yield an inaccurately higher reading from gamma measurement patterns which were designed with a full 0-255 computer monitor palette in mind.

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post #354 of 2973 Old 08-09-2005, 07:59 PM
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My comment was more to the effect the glass has on setting black levels with a mid or high (50%) APL. CRT is known for the best blacks, however the direct view CRTs, usually have the poorest ANSI contrast ratio performance of all. The thicker the front glass, the larger the affected area of internal light reflection. The light that reflects back at an angle from the front surface of the glass has more glass to travel through spreading the area. Any light source that hits a portion of the phosphor that is not the direct image, hurts black levels.

ABC is terrible about making their HD programs too dark.

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post #355 of 2973 Old 08-09-2005, 08:36 PM - Thread Starter
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Quote:
Originally Posted by GlenC View Post

The thicker the front glass, the larger the affected area of internal light reflection. . . . Any light source that hits a portion of the phosphor that is not the direct image, hurts black levels.

Oh, agreed. My black-level measurements are not made with bright material present. Program fade-outs give me an opportunity to see the edge of the 16:9 area relative to the unscanned area of the tube. Absent that, with a little practice, one can make decent judgements based on the appearance of the video. Either tow low or too high a black level will appear inferior to a satisfactory setting.

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post #356 of 2973 Old 08-10-2005, 09:06 PM
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Couple of questions:

1) I assume it's ok to have a little bit of a light (glow) emmit from the tube even if you have your source, let's say DVD player, off? I assume so.

2) My DVD player is upscaling to 1080i and I believe the TV is using the HD color matrix (SMPTE 296M), but my Zenith is using the SD color matrix (SMPTE 170M). I can go into the CXA2171 menu and change the MTRX from 1 to 0 and that will treat 1080i sources with the SD color matrix (someone found this out with their Sony TV), but it also treats C6 that way too and I have a HDTV tuner and it uses the HD color matrix. The differences seem subtle, but does anyone know a SM item that might correct this for my C5 1080i source only? TIA
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post #357 of 2973 Old 08-11-2005, 02:19 PM
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1) I assume it's ok to have a little bit of a light (glow) emmit from the tube even if you have your source, let's say DVD player, off? I assume so.

If you turn all your ambient light off, and wait till your eyes adjust to the dark, then yes, you probably should see a slight glow from scanned areas (to borrow Ken's term) of the screen, even with a totally black picture. You may even see a slight glow from unscanned/0-voltage areas. IMO though you should not really be able to see a detectable difference in black between the scanned and unscanned areas with your ambient light on. Just my 2c. YMMV. The "pedestal of grey" may be your best gauge though. If blacks in dark scenes look more like a very dark grey than black, then your Brightness may be a little too high. Some TVs (especially ones with badly adjusted grey scales) may lose too much shadow detail set this way though.
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2) My DVD player is upscaling to 1080i and I believe the TV is using the HD color matrix (SMPTE 296M), but my Zenith is using the SD color matrix (SMPTE 170M). I can go into the CXA2171 menu and change the MTRX from 1 to 0 and that will treat 1080i sources with the SD color matrix (someone found this out with their Sony TV), but it also treats C6 that way too and I have a HDTV tuner and it uses the HD color matrix. The differences seem subtle, but does anyone know a SM item that might correct this for my C5 1080i source only? TIA

That's an excellent question, Hef. This is an issue that I have only recently begun to delve into a bit myself, so take anything I have to say on this subject with a very large grain of salt... but I guess the developing consensus is that the player or video input device should make the necessary color adjustment when outputting 720p/1080i, to accomodate the HD color space on the TV.

I don't think I've run across an input level adjustment for the HD color space on my 34XBR800 so far, but that doesn't mean that there isn't one hidden somewhere else in the various codes. If noone else has an idea on this, then Sony's Non-Authorized Service Tech Support might be able to give a more definitive answer.

Since you brought the issue of different color spaces up...

***A word of advice regarding CXA2171/MTRX-- On my 34XBR800, this item does not work like most of the other SM items with respect to saving and recalling from memory. It appears to be one of a handful of settings which are memory-independent.***

In addition, I wouldn't be surprised if the CXA2171/CBGN, CRGN, YGN offsets were designed expressly for the purpose of making minor adjustments to color decoding between the SD and HD color matrices. (This is something we touched on a bit earlier in the thread.)

I'm not sure what the original MTRX setting was on my TV anymore, but somehow it also ended up at 0

If you can input color bars or a pattern like this at 33.75khz (1080i or 540p), then you can clearly see the changes in color decoding between the different MTRX settings by switching different color guns on and off with 2170P-2/RGBS.

Is there any chance Zenith might release a firmware update to correct any potential color issues on their 720p/1080i output?

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post #358 of 2973 Old 08-11-2005, 03:14 PM
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Just thought of a possibility re the MTRX setting...

You guys with newer Sonys have an advanced "Monitor" and "Default" display mode on your TV which can store different color decoder settings (which my 34XBR800 can't). So maybe those two advanced display modes can store different HD color matrices (MTRX) as well. Might be worth a try anyway.

[Edit: based on later info in the thread, this probably wouldn't be possible anwyay, since MTRX seems to work transparently/automatically outside the SM, rather than actually being user-defineable control.]

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post #359 of 2973 Old 08-11-2005, 04:07 PM
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Originally Posted by ADU View Post

Just thought of a possibility re the MTRX setting...

You guys with newer Sonys have an advanced "Monitor" and "Default" display mode on your TV which can store different color decoder settings (which my 34XBR800 can't). So maybe those two advanced display modes can store different HD color matrices (MTRX) as well. Might be worth a try anyway.

No Zenith is no longer doing firmware upgrades on this player. And on your quote above is the Advanced Monitor something in the service menu or the user menu? I'm not sure what or if I have this on my 30HS420 and where it is.
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post #360 of 2973 Old 08-11-2005, 04:14 PM
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I believe it should be somewhere in the User Menu... if the 30HS420 has it. Somewhere perhaps under Advanced Video options. You should be able to switch between the two modes without having to go into the SM.

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