Official JVC RS20 / HD750 Calibration and CMS thread - Page 32 - AVS Forum
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post #931 of 1782 Old 01-10-2009, 04:15 PM
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Originally Posted by Manni01 View Post

I know, that's why I dismissed it too, I thought, if the gamut is not adjustable, why bother with it, but in fact, when I spent more time watching it, I really liked it, and found it dfficult to spot noticeable differences with THX+5 from a color accuracy pov, with the added bonus of a higher gamma and flat greyscale (not as flat as the one I'm tweakin now though!)

I'll spend some time A/B testing it against my CMS settings and report back how I like cinema1 in comparison. Thanks.
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post #932 of 1782 Old 01-10-2009, 04:25 PM - Thread Starter
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I haven't checked it yet but from initial reports its starting to sound like that is what they did with cinema1, plus adds a little oversaturation to spruce things up. Except of course they didn't provide a way for us to get at the internal settings so we can change the saturation to taste. Clearly this is not using the same approach as the CMS.

It's the THX+wider gamut that's the issue for me. I have no problems with people preferring a wider gamut and by the time I'm done tweaking, I may end up preferring that option. But I'd like to have a rec.709 reference that tracks well where the color temp and greyscale is calibrated properly. So that's why I had high hopes for Cinema1. It would be useful for example to toggle back and forth between this rec. 709 reference and your rec. LVDVD settings.

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It still seems very odd they would provide a CMS that doesn't act like a full CMS, and then use their own method internally to provide two separate gamuts that track linearly (THX and cinema1).

Yes, odd indeed. They may have had the THX and Cinema1 settings and processing done and then added the CMS in later. Or perhaps there was a realization that the CMS couldn't quite get to rec.709 properly so they added the other settings later. Hard to say.
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post #933 of 1782 Old 01-10-2009, 05:57 PM
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Originally Posted by lovingdvd View Post

I'll spend some time A/B testing it against my CMS settings and report back how I like cinema1 in comparison. Thanks.

I did some A/B testing between THX+5 and Cinema1. To my eyes, Cinema1 is a clear winner, because apart from certain shades of green (for exemple balloons that look green in the UP trailer look paler in THX+5), it's almost imposible to tell the difference as long as you're happy with the slight oversaturation.

For me, the fact that I can adjust gamma (by the way my last greyscale was extremely flat all accross, but I definitely don't like 2.4 reference, I lose too much dark details, so it's going to be 2.3 ref for me, which gives around 2.2 average) makes all the difference. Also it forces me to move brightness up a notch, so I suppose 2.3 also improves my on/off compared to 2.4.

Given the fact that THX is slightly undersaturated to my taste, and also given the fact that I can confirm it still has a slight green tint even with a greyscale as close as color temp can get you, Cinema1 really deserves to be tried with your favorite gamma settings and some real material. Don't let the way the gamut looks put you off, try it first and see for yourself. I would say it's in between Rec709 and RecLDvd (as it showed up on my PJ, so it may in fact be quite close to RecLDvd).

Cinema1 has definitely passed the subjective visual test for me (I watched clips of TDK, Spiderman3, Wall-E, Up, and they were all better than anything I've watched until now).

Tomorrow I plan do run a last batch of contrast measurements (both on/off and ansi), and hopefully I'll be set to resume watching movies on Monday.
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post #934 of 1782 Old 01-10-2009, 07:04 PM - Thread Starter
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Manni and lovingdvd, thanks for all of your effots. Combined you guys have saved us a lot of time and tinkering (maybe a full bulb lifetime worth lol). When I get some free time I'll experiment with Cinema1 and RecLDvd both sound promising.
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post #935 of 1782 Old 01-10-2009, 07:26 PM
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Well, either my client lucked out and just got a good unit, or you guys have got unrealistic expectations for this display. The RS20 is one of the best-measuring displays I have ever encountered. It is like a Pioneer Kuro Elite, except it is a front projector. I simply can find no grounds to criticize this thing, other than of course the fact that the CMS is broken. However, the THX mode on this unit was so good that custom color tweaks were barely necessary.

Here are the numbers.

For grayscale (low lamp), pre-calibration I got almost exactly what Kris Deering measured. The 6500K preset is blue-deficient, giving the image a somewhat yellowish tinge. Post-calibration, it was nearly perfect. Figuring out how to custom calibrate the white point in THX mode was a breakthrough. One point about this. Getting into the SM is a pain in the ass. I tried it a half a dozen times before the key combination worked. You have to press the keys VERY fast, otherwise nothing happens. I was about to give up when the client succeeded after his 4th or 5th try (he must have faster fingers than I).





The color was exemplary. Perfect? No, but better than 95% of the displays out there. My Sharp 20K is better after CMS calibration, but not by a lot. I doubt that most people--even those with discriminating eyes--would be able to tell the difference.









The pre-calibration gamma was way off because the client had the black level set much too high. But post-calibration, the gamma on this unit was as good as any I have ever seen. It was an almost ruler flat 2.3. The on/off CR was an astounding 34,000:1. This is nearly twice as good as what I measured from the RS2 and nearly quadruple the RS1 performance. I set the iris at -4. Lower than that began to seriously compromise light output with only a very small improvement in black level. With a black level any lower, I would not have been able to read any light output at all at 0% stim. As it was, all I got was 0.01 Lux (the meter's lowest level) at about 6 feet from the lens.



I just don't have anything negative to say about this. I generally prefer DLPs, because I am not rainbow sensitive and I like DLPs' white field uniformity, sharpness, and depth. But the RS20 gives up nothing in these areas and offers what looks like a nearly infinite black floor to boot.

Some of you may recall that I was very critical of the RS1. I still am. It's gamma was too low. The grayscale control was 1-dimensional and thus not very effective. The image could sometimes look flat and a little noisy. The optics were mediocre. And, finally, the color was abysmal. The RS20 has addressed ALL of those issues.

Jason indicated that he was seeing quite a bit of unit-to-unit variation, so maybe this was just a good one. But based on what I saw on the client's 110" StudioTek, this is the PJ to beat certainly in the sub-$10,000 category.

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post #936 of 1782 Old 01-10-2009, 08:39 PM
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Thanks for the report Tom. How did things look below 25% without a custom gamma to rein that in? That is one of the primary reasons folks want a working CMS - so they can get Rec 709 without being locked out of features such as custom gamma.

Also can you describe in some detail what the convergence looked like?

So given the option would you trade your 20K for the RS20? It sounds like you think the RS20 has clear advantages here but I'm wondering to what extent you think the two compare.
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post #937 of 1782 Old 01-10-2009, 09:14 PM
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Ric, one of the differences between owners and those who work on these things professionally, is that I am under certain constraints--time primarily--compared to those who live with the unit and have a virtually endless amount of time for tweaking. The client had 2 displays he wanted me to work on and it took several hours to finish. I just didn't have time for things like checking white balance below 20%, so I can't say.

There was a little color fringing when I arrived, but that was because of some misalignment in the installation. Once we got the PJ perfectly level, any convergence errors were invisible from any reasonable viewing distance. It looked sharp as a tack.

I'd have to see them side-by-side to be certain, but the RS20 has most of the advantages of the 20K but with a much lower black level. So, yes, I think I probably would trade if I could afford it, which I can't right now. Although since I have the Radiance, I'd go for the RS10. My only concern is that panel alignment errors are something of a crapshoot with 3-chippers, so I would want to make sure I got a good one.

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Thanks for the report Tom. How did things look below 25% without a custom gamma to rein that in? That is one of the primary reasons folks want a working CMS - so they can get Rec 709 without being locked out of features such as custom gamma.

Also can you describe in some detail what the convergence looked like?

So given the option would you trade your 20K for the RS20? It sounds like you think the RS20 has clear advantages here but I'm wondering to what extent you think the two compare.


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post #938 of 1782 Old 01-10-2009, 10:33 PM - Thread Starter
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Tom, thanks for the report. Glad to hear that you like the RS20. I agree there is little to criticize about it other than the broken CMS, Rigidity of THX mode (and lack of documentation on the color presets and CMS).

Yes the SM is a pita! I gave up on it and LG had to PM me and let me know that they key combo hadn't changed.

Fwiw, I would like to be able to fine tune the sub 50 IRE greyscale on mine...
Attachment 129306

The RS20 has solved all of my gripes about the RS1 too and the contrast with simultaneous lumens is pretty amazing. It should be much brighter than your 20K in high contrast mode with a simultaneously lower black level.
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post #939 of 1782 Old 01-10-2009, 11:03 PM
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Just got through some extensive A/B testing of cinema1 compared to my customized CMS settings and THX. While cinema1 is certainly much better than OOTB, I easily prefer THX +x color or my customized CMS settings.

In comparison, cinema1 was over saturated. This seems to be different than what some others are reporting when using my settings, so I suspect a different like my custom gamma or unit to unit variation.

With cinema1 on my unit the over saturation causes the colors to look off. For instance bright cyan/blue looks somewhat purple-ish (Wall-E) test. I had this same exact result from one of my early calibration attempts. I saw a few other examples of this while watching some parts of SNL.

In cinema1 yellows tend to look a bit orangish, oranges tend to look a bit redish, and reds tend to be a bit darker than expected. Also the huge shift in green toward cyan (incorrect hue) is clearly visible with some content, especially "The following preview is rated..." type of screens. Pause that screen right before the "UP" preview, then switch over to THX mode. You will see a very significant difference in the hue.

I took some photos that I'll post tomorrow. Although you can't go by colors in a such photos, I do think you can judge them relative to each other, so you can see a few examples of what I experienced.

This testing has also reinforced for me that I am very satisfied with the custom CMS I am using. Although I have spotted a few places where clipping could be seen (upon pausing and careful examination), I have yet check any scene and find my colors are off in hue or overall tone. There is the intentional over saturation which is to be expected, but oranges still look orange, yellow is still yellow etc etc.

For those looking for a quick set it and forget it, I think cinema1 is decent as a quick fix. However I would encourage those of you who have been working on this to keep at it until you can get a custom CMS you can be happy with. I think its well worth the effort. Let me know if I can help.
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post #940 of 1782 Old 01-10-2009, 11:56 PM
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Regarding this sub-20% grayscale stuff, I am very skeptical.

The only way to get a reliable color reading at that low light level (less than 0.06 fL) is to take a direct reading placing the meter very close to the lens using a diffuser.

Just as a matter of standards, this conflicts with SMPTE guidelines that all readings should be taken off the screen.

Furthermore, once you start taking direct readings with a diffuser you introduce a whole host of variables that can easily impact the accuracy of readings at all other levels of stimulus.

I am not saying that you can't get good readings this way. Rather, I question the cost-benefit ratio of doing so.

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post #941 of 1782 Old 01-11-2009, 12:47 AM
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Figuring out how to custom calibrate the white point in THX mode was a breakthrough. One point about this. Getting into the SM is a pain in the ass.

You're welcome.
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post #942 of 1782 Old 01-11-2009, 01:11 AM
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On another note, I was in sports-watching mode with my RS20 today and found that my custom gamma curve didn't take kindly to red uniforms (such as the AZ Cardinals or my beloved NJ Devils ), which looked rather flat and lifeless. I know it was the gamma curve causing this because temporarily switching to any preset gamma curves at or above 2.2 with my customized settings was bringing them back to life. I quickly figured too much of my gamma curve was below 2.2, so after the games ended I went to work with rebuilding a new one. For this new one I also targeted a gamma of around 2.4 for the bulk of the curve, but instead of starting as low as 1.8 - 1.9, I instead went for the beginning of the curve starting at close to 2.2 and very quickly rising to the 2.4 level (fully doing so by 15% stimulus), at which point it's essentially flat the rest of the way. This new curve still accomplishes the original goal of the punchier image of a higher gamma but gives you the good shadow detail of a lower gamma, essentially the best of both worlds.

For any kind of custom gamma curve building, here's what I've found is the basic procedure you should do. First, have your grayscale already tracking close to D65. At this point, I believe most of us should already have this accomplished. Then, load up the JVC preset that most closely matches what you want to target, keeping in mind that the JVC presets all track between .05 - .1 lower than what they claim. They also have a slight dip at the very top end that you should not bother trying to correct, as this is at exercise in frustration (at best) where you will endlessly be chasing around some other point of nonlinear gamma tracking if you do. Anyway, to create a lower gamma starting point, just take the 5% input point and raise it on up so its output value is close to the 5% output value of where you want the gamma curve to start. For instance, JVC's 2.2 gamma curve has the 5% output at 48, so to have your gamma curve begin at 2.2, you'll want to set your 5% output at around 50 (remember, JVC's gammas track a bit low). That should be all, but before you go into further grayscale tweaking with the individual RGB gammas, do a full grayscale reading to both make sure that your grayscale settings are still optimized as much as possible with your current gain and offset color temperature settings and that the gamma is really tracking as you want it to.

One other tip I'll share for final gamma tweaking is that you really should use 2 custom gamma curves during tweaking thanks to JVC's finicky gamma controls. The reason for this is because you don't want to make a change to a fine-tuned gamma curve only to find that JVC's interpolation / smoothing with your change actually made things worse than they previously were. For this reason, anytime you make a change that improves the tracking, copy it to the the other custom gamma you're working with, and continue working on that one. Anytime you make a change that degrades tracking, all you need to to do revert back to your prior settings is switch back to the other custom gamma mode, rather than go through the painful effort of trying to undo the changes to the gamma curves that you made. Good luck!
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post #943 of 1782 Old 01-11-2009, 02:02 AM
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Originally Posted by Googer View Post

On another note, I was in sports-watching mode with my RS20 today and found that my custom gamma curve didn't take kindly to red uniforms (such as the AZ Cardinals or my beloved NJ Devils ), which looked rather flat and lifeless. I know it was the gamma curve causing this because temporarily switching to any preset gamma curves at or above 2.2 with my customized settings was bringing them back to life. I quickly figured too much of my gamma curve was below 2.2, so after the games ended I went to work with rebuilding a new one. For this new one I also targeted a gamma of around 2.4 for the bulk of the curve, but instead of starting as low as 1.8 - 1.9, I instead went for the beginning of the curve starting at close to 2.2 and very quickly rising to the 2.4 level (fully doing so by 15% stimulus), at which point it's essentially flat the rest of the way. This new curve still accomplishes the original goal of the punchier image of a higher gamma but gives you the good shadow detail of a lower gamma, essentially the best of both worlds.

For any kind of custom gamma curve building, here's what I've found is the basic procedure you should do. First, have your grayscale already tracking close to D65. At this point, I believe most of us should already have this accomplished. Then, load up the JVC preset that most closely matches what you want to target, keeping in mind that the JVC presets all track between .05 - .1 lower than what they claim. They also have a slight dip at the very top end that you should not bother trying to correct, as this is at exercise in frustration (at best) where you will endlessly be chasing around some other point of nonlinear gamma tracking if you do. Anyway, to create a lower gamma starting point, just take the 5% input point and raise it on up so its output value is close to the 5% output value of where you want the gamma curve to start. For instance, JVC's 2.2 gamma curve has the 5% output at 48, so to have your gamma curve begin at 2.2, you'll want to set your 5% output at around 50 (remember, JVC's gammas track a bit low). That should be all, but before you go into further grayscale tweaking with the individual RGB gammas, do a full grayscale reading to both make sure that your grayscale settings are still optimized as much as possible with your current gain and offset color temperature settings and that the gamma is really tracking as you want it to.

One other tip I'll share for final gamma tweaking is that you really should use 2 custom gamma curves during tweaking thanks to JVC's finicky gamma controls. The reason for this is because you don't want to make a change to a fine-tuned gamma curve only to find that JVC's interpolation / smoothing with your change actually made things worse than they previously were. For this reason, anytime you make a change that improves the tracking, copy it to the the other custom gamma you're working with, and continue working on that one. Anytime you make a change that degrades tracking, all you need to to do revert back to your prior settings is switch back to the other custom gamma mode, rather than go through the painful effort of trying to undo the changes to the gamma curves that you made. Good luck!

Thanks Googer, this is excellent and exactly what I needed at this stage (I have managed to get an almost perfect greyscale at 30 IRE and above using color temp solely, but although I got it completely flat with gamma tweaking all accross, my gamma curve is not right and these tips will be extremely helpful.

Talking of which, could you please confirm that I need to adjust the gamma reference in HCFR to the gamma reference set in the PJ before reading the greyscale to get a correct gamma graph and a correct average calculated? I had never looked into this but my last gamma graph and average looks too wrong to be close to reality...

I understand the effect of gamma, but I need to improve my theoretical grasp of it to improve the way to control the curve and the way it measures. It would also help me to decide which gamma ref I prefer if I manage to get it to track correctly. Until now, I was chosing a gamma reference, and using the RGB gamma controls primarily to flatten the greyscale, but I understand that there is a way to control at the same time the gamma curve itself (although I'm not sure I understand how you control both at the same time). Is it by working on the white points levels for gamma and RGB levels separately for the greyscale? I know this must be obvious, but I'm quite new to this game...

Re the last tip (backup!), it was also in my last list of tips

Getting a very close greyscale with color temp makes it a very close toss up between tweaked THX and cinema1, especially if one is happy with a gamma of 2.2 or 2.3 (which is my case).

I'm going to perfect my greyscale and gamma curve to the limit of my ability , then do a bit more compare. But last night, THX looked MUCH better with a very good greyscale (and color adjusted to at +5 to compensate for the slight undersaturation). So I would need to get a REAL improvement from my gamma settings to make up for the weird gamut of Cinema1 (the button on the remote control is not enough for me).

2.4 ref (my starting point before my gamma tweak yesterday) was too high to my taste (too much detail lost in dark scenes). I didn't have time to start over, but I prefered it when I adjusted "on the fly" down to reference 2.3 (which I know corrupts the results somehow).

So I plan to start again with a 2.3 ref and follow your tips. Thanks again.
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post #944 of 1782 Old 01-11-2009, 02:30 AM
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Manni and lovingdvd, thanks for all of your effots. Combined you guys have saved us a lot of time and tinkering (maybe a full bulb lifetime worth lol). When I get some free time I'll experiment with Cinema1 and RecLDvd both sound promising.

You're welcome, but although others used less bandwidth than LD and I did lately - probably because they gave up on the CMS before we did - they made great contributions (Googer and Capitano for example to name just two, without them we wouldn't be able to tweak the THX preset, which is probably the single most important finding of this whole thread). Not to mention yourself and all the others...

I'm the one who is learning here, so my trade off was to offer lamp hours and midnight oil to gain priceless knowledge and experience in calibration. A bargain! Thanks again to all here who accepted a complete rookie and shared generously their knowledge with me, while remaining politely silent every time I publicly embarrassed myself. The learning curve was (and still is) steep, but the amount I've learned - or at least believe I've learned - here is amazing, you guys rock!
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post #945 of 1782 Old 01-11-2009, 02:43 AM
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Originally Posted by TomHuffman View Post

One point about this. Getting into the SM is a pain in the ass. I tried it a half a dozen times before the key combination worked. You have to press the keys VERY fast, otherwise nothing happens. I was about to give up when the client succeeded after his 4th or 5th try (he must have faster fingers than I).

Yes, you need to be faster than on the RS1. Daphne fast.
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The on/off CR was an astounding 34,000:1. This is nearly twice as good as what I measured from the RS2 and nearly quadruple the RS1 performance. I set the iris at -4. Lower than that began to seriously compromise light output with only a very small improvement in black level.

I measured somewhere between 30000:1 and 50000:1. Black level measuring variance was too big for more precise statements.
I also find < -4 too dim. I actually went for 0. That gives me the best pop/depth in my bat cave most of the time.
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Some of you may recall that I was very critical of the RS1. I still am. It's gamma was too low. The grayscale control was 1-dimensional and thus not very effective. The image could sometimes look flat and a little noisy. The optics were mediocre. And, finally, the color was abysmal. The RS20 has addressed ALL of those issues.

The RS1 one needs an external video processor such as the Radiance to shine. Otherwise color and gamma are unacceptably off. With that fixed the RS1 is still no match for the RS20 but very watchable nonetheless.
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post #946 of 1782 Old 01-11-2009, 02:47 AM
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Originally Posted by TomHuffman View Post

Regarding this sub-20% grayscale stuff, I am very skeptical.
The only way to get a reliable color reading at that low light level (less than 0.06 fL) is to take a direct reading placing the meter very close to the lens using a diffuser.
Just as a matter of standards, this conflicts with SMPTE guidelines that all readings should be taken off the screen.

I see no need for that if you have a rather neutral screen. Anyway, it's not workable with projectors that have such dark grays for black. Even measuring from the lens with one position was not working any more. I had to use 2 positions. One for IRE 40-100 and one for 0-30.
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Furthermore, once you start taking direct readings with a diffuser you introduce a whole host of variables that can easily impact the accuracy of readings at all other levels of stimulus.
I am not saying that you can't get good readings this way. Rather, I question the cost-benefit ratio of doing so.

I use only readings from the lens with a diffuser. I'm not aware of any problems here.
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post #947 of 1782 Old 01-11-2009, 02:59 AM
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Originally Posted by TomHuffman View Post

Ric, one of the differences between owners and those who work on these things professionally, is that I am under certain constraints--time primarily--compared to those who live with the unit and have a virtually endless amount of time for tweaking. The client had 2 displays he wanted me to work on and it took several hours to finish. I just didn't have time for things like checking white balance below 20%, so I can't say.

There was a little color fringing when I arrived, but that was because of some misalignment in the installation. Once we got the PJ perfectly level, any convergence errors were invisible from any reasonable viewing distance. It looked sharp as a tack.

I'd have to see them side-by-side to be certain, but the RS20 has most of the advantages of the 20K but with a much lower black level. So, yes, I think I probably would trade if I could afford it, which I can't right now. Although since I have the Radiance, I'd go for the RS10. My only concern is that panel alignment errors are something of a crapshoot with 3-chippers, so I would want to make sure I got a good one.

Thanks for your report Tom, although I was naively hoping you would crack the CMS, not that you would settle for tweaked THX without even trying!

Generally, I agree with you, the RS20/HD750 offers one of the best picture at this price level, and if you remember I was one of those in the thread regularly trying to bring a bit of positivity while everyone was doom and gloom...

Indeed, the "broken" CMS is not such a big issue. But the very fact that you would go for an RS10 with a radiance illustrates why those like us who have paid for a 750 and not a 350 were not ready to give up on the CMS functionality that easily...

Yes, tweaked THX gives acceptable results, but we paid extra money for the 750 mainly to get a CMS allowing us to fine-tune the PJ to taste or to REC709, and to adjust gamma/greyscale, both of which the THX preset doesn't fully allow. It turns out what we get are two presets which give satisfying results depending on our priority (Cinema1 for gamma/greyscale or THX for color acuracy), but no full CMS (unless we have failed to understand how it really works) which would allow us to get both at the same time.
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post #948 of 1782 Old 01-11-2009, 03:05 AM
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Manni, Do you have Prince Caspian? If so can you check the beginning of the film (dark scenes in the castle and outside when he escapes). I find THX looks very different with these scenes to the other presets. With THX the greys are very green, with the others they are very blue. This is with using the same greyscale/color temp.
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post #949 of 1782 Old 01-11-2009, 03:19 AM
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Originally Posted by JeffY View Post

Manni, Do you have Prince Caspian? If so can you check the beginning of the film (dark scenes in the castle and outside when he escapes). I find THX looks very different with these scenes to the other presets. With THX the greys are very green, with the others they are very blue. This is with using the same greyscale/color temp.

I'll ask a friend if I can borrow it from him and I'll report. Anything in the trailer, which I have?

In the meantime, can you check the UP trailer on the Wall-E BD? I was checking THX against Cinema1, and found the green in THX very pale/yellow (or is it the opposite, and cinema1 more oversaturated, which would make sense?). It is probably due to the green oversaturation of the cinema1 preset, but it felt like THX wasn't right, not the opposite. I haven't seen it "right" (who knows what each ballon is supposed to look like), but I'd be interested to find out what you think, as this was one of the most obvious differences I noticed between the two presets.
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post #950 of 1782 Old 01-11-2009, 04:27 AM
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Just check the disney castle at the biginning of any disney movie and look at the sky , I believe the problem is cyan. THX Cyan is weak and greenish, with cinema1 it is far too blue. I also found the cinema1 colours to be far too dark. I still find my own setting to be a big improvement on both THX and Cinema1.
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post #951 of 1782 Old 01-11-2009, 04:29 AM
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Originally Posted by TomHuffman View Post

I simply can find no grounds to criticize this thing, other than of course the fact that the CMS is broken.

Exactly!

Thanks for the report Tom and it mirrors my own findings and is why I have not touched the CMS in a few weeks.

The Cinema 1 preset failed subjectively for me yesterday. Will Smith's skin color in Hancock looked completely unnatural. It was too red. I switched back to THX mode about two minutes into the movie.

I am now convinced that I have been exposed to the Color Accuracy virus, perhaps through some posting exchange with Bob Sorel.

Affable Nitwit
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post #952 of 1782 Old 01-11-2009, 05:20 AM
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Originally Posted by mhafner View Post

I use only readings from the lens with a diffuser. I'm not aware of any problems here.

It can depend on your meter and how linear it is with the diffuser. One thing readings from the lens misses is any color-shift that can be present in screens with gain coatings and some rooms with color on the walls. Contrast readings from the lens only check/confirm projector performance, not the entire system.

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post #953 of 1782 Old 01-11-2009, 05:29 AM
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It can depend on your meter and how linear it is with the diffuser. One thing readings from the lens misses is any color-shift that can be present in screens with gain coatings and some rooms with color on the walls. Contrast readings from the lens only check/confirm projector performance, not the entire system.

Naturally. I have a < 1 gain screen that is THX certified and should be quite neutral. The probe is an EyeOnePro.
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post #954 of 1782 Old 01-11-2009, 05:32 AM
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Originally Posted by mhafner View Post

Naturally. I have a < 1 gain screen that is THX certified and should be quite neutral. The probe is an EyeOnePro.

If you are using the diffuser shipped with the EyeOne Pro it is not color stable. It is also a very poor grade diffuser from a light transmission standpoint. The diffuser calibration for that diffuser will shift rather quickly with time.

I am a big fan of using diffusers, but you must understand the limitations of your equipment and use it all properly.
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post #955 of 1782 Old 01-11-2009, 05:54 AM
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Originally Posted by mhafner View Post

I also find < -4 too dim. I actually went for 0. That gives me the best pop/depth in my bat cave most of the time.

Are you folks using low or high bulb mode?

Also, mhafner, could you tell me what size/gain screen you are using?

Thanks,
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post #956 of 1782 Old 01-11-2009, 06:55 AM
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Originally Posted by Lawguy View Post

Exactly!

Thanks for the report Tom and it mirrors my own findings and is why I have not touched the CMS in a few weeks.

The Cinema 1 preset failed subjectively for me yesterday. Will Smith's skin color in Hancock looked completely unnatural. It was too red. I switched back to THX mode about two minutes into the movie.

I am now convinced that I have been exposed to the Color Accuracy virus, perhaps through some posting exchange with Bob Sorel.

I'll check Will in I, Robot.

In TDK, I did a lot of back and forth between c1 and THX to check skin tones, and it looked very close.

I'm sure you've not caught any virus, it's more probably me who is color blind. I' quite sensitive to colors for which I have a direct point of reference (ie skin tones), but otherwise as long as nothing looks obviously wrong especially in the greyscale, it's quite easy to keep me happy.
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post #957 of 1782 Old 01-11-2009, 06:56 AM
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Originally Posted by TomHuffman View Post

Getting into the SM is a pain in the ass. I tried it a half a dozen times before the key combination worked. You have to press the keys VERY fast, otherwise nothing happens. I was about to give up when the client succeeded after his 4th or 5th try (he must have faster fingers than I).

I plan to program a macro on my Pronto TSU9400 remote so that I can have a button that says Service Menu that sends the commands in order with a slight delay between them. If it works it should eliminate all of the key pressing.

Never become so involved with something that it blinds you.
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post #958 of 1782 Old 01-11-2009, 06:58 AM
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Quote:
Originally Posted by JeffY View Post

Just check the disney castle at the biginning of any disney movie and look at the sky , I believe the problem is cyan. THX Cyan is weak and greenish, with cinema1 it is far too blue. I also found the cinema1 colours to be far too dark. I still find my own setting to be a big improvement on both THX and Cinema1.

Will check when I get a chance. I know Cinema1 has a low luminance, but again in my settings it didn't look much darker than THX (but it did look darker than RecLDVD).

What are your own settings? A LDVD version? Are you using the Lumagen at all?
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post #959 of 1782 Old 01-11-2009, 07:00 AM
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Originally Posted by Bulldogger View Post

I plan to program a macro on my Pronto TSU9400 remote so that I can have a button that says Service Menu that sends the commands in order with a slight delay between them. If it works it should eliminate all of the key pressing.

That's a great idea. Do you think I could do the same on my Harmony One? Do we have a list of the control codes?

I don't think I would have succeeded entering the service menu without JeffY's kind help.

I asked for it in public though so everyone could benefit from my ignorance(my usual strategy as everyone will have noticed).
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post #960 of 1782 Old 01-11-2009, 07:30 AM
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That's a great idea. Do you think I could do the same on my Harmony One? Do we have a list of the control codes?

I do RS232 control and only have the codes for that. You should have the capacity to learn the IR codes?

Never become so involved with something that it blinds you.
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