JVC RS1 review!!! (of sorts) - Page 4 - AVS Forum
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post #91 of 451 Old 12-24-2006, 07:57 PM - Thread Starter
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Quote:
Originally Posted by Bulldogger View Post

I have a feeling Williams Phelps is going to be a very busy man. He hasn't developed an optimization for this projector yet as it obviously is still not in production. When it does ship and I get mine, I want to be one of the first to let William work his magic.

Yeah the shading comments alone suggest that the RS1 will greatly benefit from a little post-sales tuning. Anyone know when Wm will be offering his services? All in all it sounds as though JVC is following Sony's lead to letter as far as how the Ruby was released. If this unit is any indication it sounds as though in order to meet this sort of price point that QC will come in a little lower than we had hoped, but still better than Sony.

Also has anyone heard final word if the HD1 will be sold here in the US with the silver faceplate via the JVC consumer division while the JVC Pro division simultaneously sells the RS1 with a black faceplate? The US JVC consumer division website implies exactly such. If this happens it implies that JVC may be undercutting some of their higher-end dealers similar to what Sony did with the Ruby. Back to your point though, if Sony and JVC engage in a price war and start cutting corners, Wm is going to be a very busy man lol.
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post #92 of 451 Old 12-24-2006, 07:58 PM
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Quote:
Originally Posted by Mark Petersen View Post

LOL! I hate being the messenger.. they always get shot (or worse) I'm glad that people haven't run me out of town.
.

Mark, thanks a lot. You are doing a great job. I was happy with 10000:1 contrast. If I get that spec with 650 or so lumens, that's KILLER.

Never become so involved with something that it blinds you.
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post #93 of 451 Old 12-24-2006, 07:59 PM
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Originally Posted by oliverlim View Post

To be fair to many, this "misconception" probably came about due to auto iris implementation. Look at it this way, Ruby/Pearl/LCDs with 10K:1 to 17k:1 ONOFF contrast ratio and about 200-300:1 Ansi. Flat picture compared to a 3000:1 ONOFF and 400:1 ansi looking 3D with pop. You draw your own conclusions. Note I said misconception as it may turn out to be true in the end.

However with a autoiris implementation, you still get about 1500:1 to 3000:1 contrast ratio at any one time. That probably means that a DLP with 3000:1 with only about 400:1ansi will have more 3D pop then any of the above examples I gave. But a projector with 4 to 5 times more NATIVE ON/OFF but maybe twice as little ansi contrast, who knows? The massive increase in NATIVE ON/OFF may actually outgun the twice lower Ansi Contrast.

Then we have MTF being thrown into the picture. I have seen the JVC 2K and although it is mightly sharp, it does have this haze and the picture just does not seem to pop up compared to the S11 at the same place. So if DLP cant do MTF well but the JVC 2K does MTF well, can we draw any conclusions from this? I do not know.

Again,hopefully the 2 parties with the JVC can get their hands on a Sharp or S11 or maybe even a Mit 3100 side by side to confirm if this is true :-p

Oliver

Yes auto iris puts a whole new side to the argument, all of my posts was considering native ONOFF and only native ONOFF.

I don't believe you can "discuss" auto iris in this manner since there are so many factors in the implementation that makes its behavior very unpredictable.

The only auto iris out there that i consider doing a "good" job is the Sony irises, and i have seen and calibrated on almost all of the auto iris PJ out there.

Again i am not bashing ANSI at all, i would my self love to have 500+ ANSI, but for know i consider ONOFF to be the great weakness and increases in NATIVE ONOFF at this time has IMO a greater impact on overall contrast performance.

My purpose was to shed some light on the subject so that people perhaps can see the interplay of the parameters and not only say "Dark scenes is ONOFF, mixed are ANSI"

What is mixed? the ANSI checkerboard is 50APL that is NOT a mixed scene in a movie which is below 20.

I cant wait to see this JVC, it is the PJ i have been waiting for
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post #94 of 451 Old 12-24-2006, 08:06 PM - Thread Starter
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Quote:
Originally Posted by Bulldogger View Post

Mark, thanks a lot. You are doing a great job. I was happy with 10000:1 contrast. If I get that spec with 650 or so lumens, that's KILLER.

Thanks! This is the busiest job I've ever had - it's a good thing that it pays well lol!! I also agree with you, I'll be ecstatic with 10K:1 and 250:1 with 650 or so lumens. This is a 5x increase in on/off CR and a 2.5x increase in ANSI and a nearly 50% increase in brightness from what I have right now - and I'm happy with what I have right now with the exception that I'd like for dark scenes to be more convincing. The RS1 should be quite the upgrade...
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post #95 of 451 Old 12-24-2006, 08:14 PM
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Quote:
Originally Posted by oliverlim View Post

Flat picture compared to a 3000:1 ONOFF and 400:1 ansi looking 3D with pop. side by side to confirm if this is true :-p
Oliver

Nonsense! There are many people who have moved from a 3,000:1 / 400:1 ANSI CR DLP who will tell you that a Ruby/Pearl has a much better 3D picture.
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post #96 of 451 Old 12-24-2006, 08:18 PM
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Quote:
Originally Posted by Mark Petersen View Post

Yeah the shading comments alone suggest that the RS1 will greatly benefit from a little post-sales tuning. Anyone know when Wm will be offering his services? All in all it sounds as though JVC is following Sony's lead to letter as far as how the Ruby was released. If this unit is any indication it sounds as though in order to meet this sort of price point that QC will come in a little lower than we had hoped, but still better than Sony.

Reality starts to set in.

What facts do we have to support this repeated claim that the JVC units will be a lower number of out of spec units that the Sony?
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post #97 of 451 Old 12-24-2006, 08:46 PM
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Can somebody PM me the price on the Preorder, so I can see if it is near my price bracket.

Thanks
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post #98 of 451 Old 12-24-2006, 08:46 PM - Thread Starter
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Quote:
Originally Posted by HoustonHoyaFan View Post

Reality starts to set in.

We all knew our sky high expectations were just a tad too high

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What facts do we have to support this repeated claim that the JVC units will be a lower number of out of spec units that the Sony?

None whatsoever. It's rampant speculation lol . Well it's *slightly* better than that. We have the comments on this particular unit from our anonymous reviewer comparing this unit to his Pearl and also the comments by the JVC reps at the Expo who have said that the RS1 shading should be similar to current JVC projectors. I agree though the proof will be in the pudding. Which is why I can't wait to hear Jason, gregr's and other reviewers comments. The more people post the more of a feel we will get about these units.
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post #99 of 451 Old 12-24-2006, 08:49 PM
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"Yeah the shading comments alone suggest that the RS1 will greatly benefit from a little post-sales tuning."

From what I can tell all we're talking about is a slightly elevated black level in the corners on full blackout.

If William can lower the black level in the corners, that's great, but I'd guess he'd have to raise the black level in the middle.

If that's the case, I'd rather keep the better on/off CR in the middle of the picture and save my money.

Noah
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post #100 of 451 Old 12-24-2006, 09:00 PM - Thread Starter
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Originally Posted by noah katz View Post

"Yeah the shading comments alone suggest that the RS1 will greatly benefit from a little post-sales tuning."

From what I can tell all we're talking about is a slightly elevated black level in the corners on full blackout.

If William can lower the black level in the corners, that's great, but I'd guess he'd have to raise the black level in the middle.

If that's the case, I'd rather keep the better on/off CR in the middle of the picture and save my money.

Check post #77, the reviewer thought that shading was better than his Pearl but that there was still room for improvement. I may not have posted this (sorry, my bad) but he also said that there was slight white field coloration.
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post #101 of 451 Old 12-24-2006, 09:38 PM
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Hi Mark - thanks for the hard work on this! I was wondering if you could get a few more questions answered:

1) How did the unit calibrate at the low end, say from 5-30 IRE? cine4home could not test I am am wondering how evenly it calibrates down low.

2) Are there any controls for moving the hue, saturation or lightness of the primaries/secondaries (in other words ANY sort of color management)?

3) Can we get some comments from the reviewer about just how sharp it is especially compared to the Ruby and Pearl, and perhaps the Sharp 20K if the reviewer has experience with that? I know he said it looked sharp, but I'm wondering just how sharp.

4) How about some comments from the reviewer about overall how this pj compares to others in its class in terms of overall PQ?

Thanks!

Also related to the on/off measurements... I wanted to point out (as also touched on by Phelps) that just a slight measurement error (either human error or instrumentation rounding even) can make the difference between at 13,000:1 reading and a 15,000:1 one. Also I imagine there's enough variation within the production units to account for this difference. I'll be interesting to see more calibration results as others get these units.
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post #102 of 451 Old 12-24-2006, 09:41 PM
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Quote:
Originally Posted by Mark Petersen View Post

Check post #77, the reviewer thought that shading was better than his Pearl but that there was still room for improvement. I may not have posted this (sorry, my bad) but he also said that there was slight white field coloration.

Problem is, the Pearls vary from unit to unit. Despite everyone wth some prior JVC experience ensuring me otherwise, this may end up being the case with the RS1 as well. I realize the JVCs have a better rep over the last 1/2 dozen years, than the Sonys do over the last two- but since JVC is making a concerted effort to play against Sony in the same ballpark, it just may stand to reason that they start to play by the same rules as well- and may have to begin to adopt a more liberal set of tolerences -simply out of economic neccessity.

could it be that both sets of number are correct and that we are seeing the first hints of the spectrum that individual production units will fall somewhere within?
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post #103 of 451 Old 12-24-2006, 09:50 PM
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So if DLP cant do MTF well but the JVC 2K does MTF well, can we draw any conclusions from this?

A high quality DLP like the Marantz is capable of delivering a higher system MTF than any other technology to date....around 90% if memory serves.
Quote:


However with a autoiris implementation, you still get about 1500:1 to 3000:1 contrast ratio at any one time.

That depends on the projector. The Ruby is capable of roughly 3k:1 to 5k:1 at any one time....close to twice what you seem to think is possible.
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The only auto iris out there that i consider doing a "good" job is the Sony irises, and i have seen and calibrated on almost all of the auto iris PJ out there.

Agreed 100%...but I haven't seen them all.
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post #104 of 451 Old 12-24-2006, 09:58 PM - Thread Starter
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Lovingdvd, I'll try and get some answers to your questions along with lumens vs throw. It won't happen until after Christmas though.

I also agree with you that there is a fine difference between 13k:1 and 15k:1, the reviewer exhaustively checked his equipment (actually tried a few different sensors to ensure accuracy and all matched each other very closely). He also made sure that the contrast settings were at their rails and HDMI was set to PC levels etc. He also treated the projector and sensor with blackout cloth to make sure ANSI wasn't affected (it wasn't). Like I mentioned though the CT at 100IRE was low and the CT at the bottom was high so a good D65 calibration will likely raise lumens and CR to some extent (although not to 15k:1).

Paulidan, I totally agree that JVC's QC with the RS1 is so far a big unknown. Only time will tell. It's also quite likely that these and Cine4home's numbers are accurate and we're just seeing deviation in production units. If, down the road someone just happens to get a magic 18k:1 model and wants to sell it PM me
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post #105 of 451 Old 12-24-2006, 10:30 PM
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Quote:
Originally Posted by HoustonHoyaFan View Post

Reality starts to set in.

What facts do we have to support this repeated claim that the JVC units will be a lower number of out of spec units that the Sony?

The only thing I can think of is Matsushita's impending sale of JVC to possibly Kenwood (they're in talks despite some inconsistent public denials). Ever tried Kenwood's customer service for warranty issues? You don't want to know...
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post #106 of 451 Old 12-24-2006, 10:39 PM - Thread Starter
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Originally Posted by Bob Sorel View Post

A high quality DLP like the Marantz is capable of delivering a higher system MTF than any other technology to date....around 90% if memory serves.

To be precise this is for 1080p source resolutions. It's interesting to point out that the quoted MTF numbers are the value at the resolution limit of the projector (1080p in this case). With a digital projector the MTF goes to 0 once the native pixel resolution is exceeded. A higher resolution projector like a 4k will go to higher frequencies (4k source resolutions) before hitting the wall and their sharpness at lower 2k source resolutions will be correspondingly high and may in fact be higher than the best 1080p DLP (I don't know if this has ever been published). Another interesting thing that happens is that non-fixed pixel devices (CRT) have a descending ramp shaped dropoff in MTF because they are only limited by bandwidth and spot size so even though they may have a much lower MTF at 1080p they may (depending on the CRT of course) actually have measurable (but low) MTF beyond 1080p and could arguably be considered as having better resolving ability at these higher resolutions (even if it looks terrible!). For consumer use though we are currently stuck at 1080p for the upper limit in source resolution so at these limits you're right 1-chip 1080p DLP is currently the best (excepting 4k projectors that is).

Also a MTF of 90% for 1080p DLP probably isn't far off the mark, but have you seen a white paper or measurements that actually show this? I've looked for this data but have so far come up empty
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post #107 of 451 Old 12-24-2006, 11:31 PM
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Quote:
Originally Posted by Mark Petersen View Post

Modified ANSI CR (using Greg Rogers methodology):
258:1 normal lamp setting.
260:1 high lamp setting.
...
Updated measurements:
Modified ANSI CR yields repeatably consistent numbers of 270:1 (273:1 max).

Thanks for the report. I guessed 260:1 in your thread where we were asked to guess the ANSI CR, so at first glance it and using Greg's modified ANSI CR approach my guess was 220:1, so it looks like I was overly conservative and JVC has come in higher. Always glad to see them do better than I expected.

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post #108 of 451 Old 12-25-2006, 12:40 AM
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This is going to be interesting. I was hoping for higher ANSI contrast numbers, but as several people have pointed out, there are several other factors to consider in determining what kind of image depth we will get from the RS1.

I just need Greg Rogers' review a few days before my unit is due to ship!
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post #109 of 451 Old 12-25-2006, 01:45 AM
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Quote:
Originally Posted by Mark Petersen View Post

... the reviewer exhaustively checked his equipment (actually tried a few different sensors to ensure accuracy and all matched each other very closely). He also made sure that the contrast settings were at their rails ....

Full-field (on-off) contrast ratio measurements have no relevance unless they are made using the projector's calibrated, normal operating settings. (Remember that the full-field contrast ratio is just a way of expressing the black level relative to the reference white level in normal operation.) I've never seen a case where the contrast setting (user or service menu) would be at maximum ("at their rails"). If you want to compare the contrast ratios of different projectors it is mandatory that they be fully calibrated (grayscale, etc) prior to making the measurements, and the calibration is not changed while making the measurements. For that reason I provide a plot (and table) of the grayscale dE deviation from D65 for the measurements. It is usually possible to simply increase the Contrast (white level) setting (or equivalent combinations of RGB gain controls) to increase the measured contrast ratio by 25% or more. However, the dE deviation is then unacceptable. I normally limit the dE deviation to 3 dE at the maximum white level used for the contrast ratio measurement (Note you must calibrate the remaining entire grayscale for minimum dE deviation - a single dE value at the white reference is meaningless - and therefore the contrast ratio can not be increased without degrading the grayscale). However, if there is a significant increase in lumens/contrast ratio available by increasing the dE slightly, I will also provide those lumens/contrast ratio vs dE numbers because the user may wish to run the projector in a brighter mode for non-critical viewing.

Greg Rogers
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post #110 of 451 Old 12-25-2006, 02:34 AM
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thanks Zoomair, very very interesting commentary.
indeed, CRT was always raved about but it had very high on onff and poor ansi.
and a good CRT with a good scaled signal still remains king for many.
the HD1RS1 is reaching this level.
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post #111 of 451 Old 12-25-2006, 02:35 AM
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From the anonymous reviewer in Mark's updated first post:

Verbal description:
"But OMG, the depth and the detail. And when TheaterTek ends and the logo comes back up it's this amazing graphic in a sea of black. I can hardly see the screen.

The Pearl looks just OK compared to this. I'll take 12000:1 without DI over 15500 with DI any day. And very very little corner brightening

OMG is it crisp.

I doubt anyone who has one on order is going to regret it."


The specs and numbers are wonderul for discussion and are very exciting and informative, but this description, which seems to just keep coming from informed and experienced people seeing this unit is what really gets me going!

Can't get one of these puppies soon enough!

Disclaimer: Totally biased RS1 fanclown...cannot be relied upon for any type of objectivity regarding same. You have been warned.
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post #112 of 451 Old 12-25-2006, 02:44 AM
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Quote:
Originally Posted by Mark Petersen View Post

To be precise this is for 1080p source resolutions. It's interesting to point out that the quoted MTF numbers are the value at the resolution limit of the projector (1080p in this case).

Yes indeed, MTF (modulation transfer function) is a function not a single point. The shape of the curve is critically important to the perception of sharpness, while levels at the highest spatial frequencies determine the perception of resolution (fine detail).

Quote:
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Another interesting thing that happens is that non-fixed pixel devices (CRT) have a descending ramp shaped dropoff in MTF because they are only limited by bandwidth and spot size so even though they may have a much lower MTF at 1080p they may (depending on the CRT of course) actually have measurable (but low) MTF beyond 1080p and could arguably be considered as having better resolving ability at these higher resolutions (even if it looks terrible!).

This was particularly important when fixed pixel projectors were limited to 720p native pixel resolution. It was very common for CRT projectors to display higher resolution but much less sharpness with 1080i/p sources

Greg Rogers
Video Engineer/Product Designer

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post #113 of 451 Old 12-25-2006, 03:05 AM
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So, Greg, it looks like your CR measurements are taken with maximized video dynamic range and therefore minimum headroom before significant changes in color temperature take place (greater than dE of 3). Would this be a fair description of your methodology?

I know that a lot of people are capable of calibrating displays properly, but I also have to wonder how many of them take the time to extract maximum dynamic range (minimum headroom) during this calibration process versus how many of them simply work from a known starting point (factory calibration that may or may not be maximized) and then adjusting grayscale tracking from there without first checking and maximizing dynamic range. If this procedure is/was not done, then that could easily account for significant reductions in on/off CR, while not holding maximum white within a specified and consistent dE deviation (like the 3 dE number that Greg uses) could lead to overblown, inaccurate CR figures.
Quote:


The specs and numbers are wonderul for discussion and are very exciting and informative, but this description, which seems to just keep coming from informed and experienced people seeing this unit is what really gets me going!

Sooner or later the "specs and numbers" will be revealed that will explain scientifically why people are making the comments they are making. I'm pretty confident that it will be some sort of "magic combination" of on/off CR, intra-scene CR, optics quality,color and luminance uniformity, and colorimetry that will account for all of the "wows", and not be limited to a single factor such as ANSI CR.
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post #114 of 451 Old 12-25-2006, 03:28 AM
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Quote:
Originally Posted by wm View Post

I've never measured a properly calibrated CRT that exceeded 10000:1 On/Off.

Your idea of proper is not everybody else's. It involves visibly gray blacks for starters which are very improper to me.
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Is there a visible difference between 13200:1 and 15000:1???

It's minimal. The relevant difference is between 10000:1 and 100000:1 and more. Which you can have on CRT if you like with little to no lack of shadow detail. It's apparently improper to you. Others beg to differ.
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post #115 of 451 Old 12-25-2006, 03:45 AM
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Quote:
Originally Posted by Bob Sorel View Post

So, Greg, it looks like your CR measurements are taken with maximized video dynamic range and therefore minimum headroom before significant changes in color temperature take place (greater than dE of 3). Would this be a fair description of your methodology?

Yes, because measurements are only meaningful if there is some way to normalize the measurement condition between products. I adjust each product for its best (most flat, minimum dE) grayscale performance across the entire grayscale range because that would be my normal operating/calibration process (i.e. best possible color/B&W performance). I then push the maximum level to a 3 dE deviation without disturbing the remainder of the grayscale, and take the contrast ratio measurement at that limit. (There are occasionally products where the dE value suddenly drops from 1 dE or 2 dE to 4 dE or greater, or pushing to 3 dE creates a significant deviation lower in the grayscale, so in those cases I would use the 1 dE or 2 dE value because there is no significant gain at 3 dE). That normalizes contrast ratio vs maximum brightness dE across projectors, but of course some projectors will produce a much better overall grayscale than others, which can be seen from my dE plots. The user (or his calibrator) must then decide how much headroom vs dE above the white reference level (i.e. 100 IRE) they may want to set during their own calibration. That will depend on the shape of the grayscale dE curve and their own preferences.

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post #116 of 451 Old 12-25-2006, 04:31 AM
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Quote:
Originally Posted by wm View Post

I've never measured a properly calibrated CRT that exceeded 10000:1 On/Off.

Is there a visible difference between 13200:1 and 15000:1???

A black level of 0.00114 vs. 0.00100 (given 15 foot lamberts at 100 IRE). A difference of 0.00014 foot lamberts (count the zeros). Maybe in a bat cave with fully dark adapted 10 year old eyes. Maybe... Break out the black flannel body suits, don't wear glasses, and turn off your cell phone!


William,

Are you going to be calibrating the HD1s?

R-S
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post #117 of 451 Old 12-25-2006, 05:43 AM
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He is. He has to actually have the RS1 to create an optimization for it. It will be after CES and likely in Feb. is what he responded via e-mail a few weeks back.

Never become so involved with something that it blinds you.
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post #118 of 451 Old 12-25-2006, 07:45 AM
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Greg - I took the "to the rails" comment to mean that the reviewer had the contrast maximized for the ideal setting without disturbing D65. If in fact he meant that he had the setting all the way maximized then we are in trouble and real on/off would be much lower. This is why I don't believe that was what he meant.
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post #119 of 451 Old 12-25-2006, 07:53 AM
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Quote:
Originally Posted by Mark Petersen View Post

I also agree with you that there is a fine difference between 13k:1 and 15k:1, the reviewer exhaustively checked his equipment (actually tried a few different sensors to ensure accuracy and all matched each other very closely). He also made sure that the contrast settings were at their rails and HDMI was set to PC levels etc. He also treated the projector and sensor with blackout cloth to make sure ANSI wasn't affected (it wasn't). Like I mentioned though the CT at 100IRE was low and the CT at the bottom was high so a good D65 calibration will likely raise lumens and CR to some extent (although not to 15k:1).

I don't quite get this though. I don't get why someone would go through all this trouble to measure and remeasure with multiple instruments without first dialing in the full grayscale exactly. Otherwise as Greg pointed out you wouldn't have a true indication of what the pj can do.

At any rate - the other option we have available is perhaps the color correction filters and driving G/B higher at the highend assuming this can be done without disturbing the color noticeably. If we can then that extra 10-15% lumens and CR should basically be a lock for getting into the 15,000 / 700 lumen that folks are driving toward.

Personally I'm not too concerned with what is being reported here regardling the lumens and CR coming up a bit short of expectations. For one, we don't know if this is inidicitive of the final results and/or if this is specific to this unit. Also I highly doubt anyone here would be able to tell the difference between 13,000:1 and 15,000:1. Remember we are talking about just a tiny fraction of lux that accounts for that difference.
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post #120 of 451 Old 12-25-2006, 08:37 AM
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Mark, thanks for relaying the information.

Any chance you could get them to measure lumens at max. zoom and max. tele?

Thanks and Happy Holidays!

Andy K.
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