AVS Forum banner

Official JVC RS20 / HD750 Calibration and CMS thread

210K views 2K replies 129 participants last post by  tstybr 
#1 ·
This thread is the official calibration thread for the RS20 and HD750. Please post any CMS and other calibration (greyscale, gamma, etc.) tips, techniques and tweaks into this thread. Please use the owners thread and other RS20/HD750 threads for other discussions not relevant to calibration. As time goes on I'll update this post with links to key posts and other references related to calibration.


Due to lack of time I haven't been able to post a formal writeup that recaps most of what is in this thread. Manni01 has graciously taken the time to do this though and you can read his write up here:
http://www.avsforum.com/avs-vb/showt...6#post15654856


When the final writeup is done I'll be sure to maintain the link above and also add any new links that come along.
 
#253 ·

Quote:
Originally Posted by dvectord /forum/post/15375079


Lawguy:

I'd also appreciate any other settings you are willing to supply. I plan on trying out several and seeing which works best on my particular one.


Please include lamp setting, and color temp and any offsets.

I'd also like to know if you have a hi power screen since I have one.


Thanks in advance and enjoy the new toy!

I use the high lamp setting and have a high power screen.


I won't supply any of my greyscale numbers because I am convinced that it would do everyone more harm than good. OOTB, the 6500k setting was pretty close for me through most of the greyscale. Use that, if you can't calibrate on your own.


The gamut numbers are probably hit or miss as well but I know from having spent time with the Lumagen HDQ and the RS1 that those numbers translated pretty well among machines. Hopefully it is true here as well.


Subjectively, things are looking very nice.



I watched a bit of Narnia on TV last night and the colors, dimensionality and pop of the picture were amazing. The outdoor ice and snow scenes looked appropriately icy and intentionally desaturated. Outdoor and forest scenes looked appropriately lush and vibrant.


Dark Knight tonight!
 
#254 ·
BAD NEWS.



I did a 100% and 75% measurements on my user1 calibrated profile and while 100% is close to perfect 75% colors are wayyyys off.


The same measurements on THX show 100% and 75% close.

So it seems that CMS doesn't work properly, if you set correct values at 100% you will get wrong values at 75%.

attached files.

Tom: what do you think about?

 

calib. 30h.zip 5.4111328125k . file

 

calib. 30h 75%.zip 2.7119140625k . file
 

Attachments

#257 ·
LG: I've tried out your settings (though on 'normal' lamp, and iris = -10) and fine them very nice. I'm alternating between them and Jason's; the pics are very similar, though with diffs. For some pics I like Jason's better, and for others yours. It's been very helpful since I haven't had time to play with it at all, and also lack any CMS experience.


PS Of course Jason's settings are specific to my pj. But what's so remarkable is that they are SO different from what you come up with. E.g., color = -25, Br = -5, Cst = 15, etc., and CMS is vastly diff. I have the feeling that there are many different combinations of settings that yield very similar pics, making it a very 'ill posed' problem.
 
#258 ·

Quote:
Originally Posted by capitano /forum/post/15378658


BAD NEWS.



I did a 100% and 75% measurements on my user1 calibrated profile and while 100% is close to perfect 75% colors are wayyyys off.


The same measurements on THX show 100% and 75% close.

So it seems that CMS doesn't work properly, if you set correct values at 100% you will get wrong values at 75%.

attached files.

Tom: what do you think about?

It looks like the CMS effects are VERY non-linear.


Here are DVD test patterns for WRGBCYM at 100%, 75%, 50%, and 25% if anyone wants to test this further.


Click here for an iso file.

Click here for DVD files.
 
#259 ·

Quote:
Originally Posted by Manni01 /forum/post/15366223


from your mini-review


It would be great if people with a colorimeter trying our settings could send back the charts they get. It may help people to realise the limited use of copying settings from another PJ if it sits on the opposite end of the scale.


Hello Manni01,


Thanks for the good job you are doing, mainly for the very detailed procedure you wrote and re-wrote. This will help to understand the nature of the CMS and the way it might work (?).


I entered your data strictly as they are from your test nbr 4. Just to see.

I'm using a Spyder2 probe and the lamp was 6/8 hours old.

I didn't work the greyscale. I have to report that this point is out of the specs by more than 500K for all modes, out of the box.

The source is my notebook and I have with HCFR all the material to check the saturations. One can see the undersaturation concern.


Anyhow, each new set of parameters you provided, improved the quality of the image.


I also produced the charts in user1 and custom1 mode as out of the box, but at 18 hours, sorry. The greyscale improved a bit during this time. One can notice the proper saturations, not perfect but pretty good shape. I did this test with the iris full open. I compared charts produced with position 0 and -14; As I expected, they are identical; this can help for an improved sensitivity of the probe at low IRE. Of course one should balance contrast and brightness with the correct iris setting.


IMO greyscale should be first fine tuned with offset, gain and gamma RGB curves before copying the advanced settings from other PJ.


I will start my own tests as from tomorrow.

My intend is to check one particular point at the step "color"; to get cie and saturation charts with different values in order to draw the response curves. Then for a given "color" adjustment, looking at the response to tint and saturation.

There are so many interactions...a Taguchi design of experiments would be great!


Mr JVC, what does "THX Certified" really involve?





 
#260 ·

Quote:
Originally Posted by capitano /forum/post/15378658


BAD NEWS.



I did a 100% and 75% measurements on my user1 calibrated profile and while 100% is close to perfect 75% colors are wayyyys off.
The same measurements on THX show 100% and 75% close.

So it seems that CMS doesn't work properly, if you set correct values at 100% you will get wrong values at 75%.

attached files.

Tom: what do you think about?

Isn't the CMS unavailable under THX? If so, could it be that JVC was very aware of the CMS limitations and knew if it was used to tweak the THX settings, they would no longer track accurately and possibly void the THX license? If so, they also knew the CMS as implemented would not only have limitations regarding the ability to set fully accurate colors at any IRE, once set, these values wouldn't track accurately as the stimulus changed! I guess what I am really asking is, in order to obtain THX certification does a display not only have to have accurate colors, but that they have to remain accurate across stimulation levels per some THX specification? If so, it follows that consumers should be able to do this for Rec 709 by whatever means JVC used for the THX preset! I really hope there is a fix in the service menu.
 
#261 ·

Quote:
Originally Posted by karrih /forum/post/15379419


I am beginning to feel that JVC should offer some guidance about proper usage of CMS and if it turns out that it is not possible to achieve good results across the gamut with the instructions a fix would be in order.

It will never happen with the RS series. JVC Professional markets their units to professional installers. The authorized resellers/installers are supposed to know how to do the setup and provide support to their customers..... The Consumer HD series, well we all know how the retail market supports their customers. Go to your local BB and try to see if they know what CMS is.
 
#262 ·

Quote:
Originally Posted by Lawguy /forum/post/15378155


OK. Here is the data. I have little idea if this is good performance:


R: 0: x .305, y .322; 25: x .387, y .321; 50: x .455, y .318; 75: x .528, y .317, 100: x, .642, y .333


G: 0: x .307, y .325; 25: x .308, y .392; 50: x .308, y .438; 75: x .307 y .489; 100: x .300, y .603


B: 0: x .302, y .318; 25: x .268 y .237; 50: x .239, y .172; 75: x .202, y .112; 100: x .153, y .070


Y: 0: x .309, y .326; 25: x .333, y .363; 50: x .353, y .398; 75: x .377, y .436; 100: x .421, y .509


C: 0: x .308, y .325; 25: x .287, y .329; 50: x .271, y .333; 75: x .254, y .334; 100: x .215, y .328


M: 0: x .305, y .323; 25: .308, y .275; 50: x .313, y .233; 75: x .312, y .193; 100: x .316, y .153


These are readings from Saturation patterns. I don't think that this is the kind od data that you wanted after reviewing you linked post. I don't have those kinds of patterns, other than 75%.

Thanks Lawguy. Wow these numbers are not very encouraging - seem to be over the place. How do the colors look as you move up %-wise in the patterns? Can you see a very visible shift in the color or does it just become brighter?


For instance the plot of red at 75% with x of .528 is grossly undersaturated. This color would be more of a pink/magenta. Does the pattern look like that (hope not!) or just a less bright version of red at 100%?


For this data did you calibrate at 100% levels or 75% levels. I wonder if the results would be different if done the opposite.


Also you published the xy values only. I think Tom was mainly after the Y portion (of the xyY) which was not posted. The idea was to see if Y tracked properly and did not clip - and that question remains. Can you please post the Y to go along with the xy data you provided for the 25-100% levels?


But in the meantime you may have highlighted even a more significant issue... I'm hoping this is just a measurement or operator error of some sort. Hart to imagine the color could be this far off as the Y % changes. I BRIEFLY played around with the CMS to dial in a quick gamut I was happy with, and in my very limited testing I didn't see any gross errors so I am hopeful this is not an actual issue (because such errors would be quite easy to spot - i.e. something magenta instead of red).
 
#263 ·
Hi,


I'm thinking about the information coming from Jason and when he said we must decrease the general saturation (color) setting. You can see here the effects of this decrease on a gamut. Those settings have no effect on 100 % but they are at 75, 50 and 25¨%




IMHO, if we must change the general saturation setting (with an effect at 25, 50 and 75 %) and after give the good place at 100 % with the CMS, it must have a problem. Maybe, it's the explanation for the (eventual) "bad" result under 100 %.
 
#264 ·
Have any of you with a RS2 & the RSVP2 processor as well as the RS20 compaired the end color result between the two?
 
#265 ·

Quote:
Originally Posted by leDahu /forum/post/15379791


Hello Manni01,


Thanks for the good job you are doing, mainly for the very detailed procedure you wrote and re-wrote. This will help to understand the nature of the CMS and the way it might work (?).


I entered your data strictly as they are from your test nbr 4. Just to see.

I'm using a Spyder2 probe and the lamp was 6/8 hours old.

I didn't work the greyscale. I have to report that this point is out of the specs by more than 500K for all modes, out of the box.

The source is my notebook and I have with HCFR all the material to check the saturations. One can see the undersaturation concern.


Anyhow, each new set of parameters you provided, improved the quality of the image.


I also produced the charts in user1 and custom1 mode as out of the box, but at 18 hours, sorry. The greyscale improved a bit during this time. One can notice the proper saturations, not perfect but pretty good shape. I did this test with the iris full open. I compared charts produced with position 0 and -14; As I expected, they are identical; this can help for an improved sensitivity of the probe at low IRE. Of course one should balance contrast and brightness with the correct iris setting.


IMO greyscale should be first fine tuned with offset, gain and gamma RGB curves before copying the advanced settings from other PJ.


I will start my own tests as from tomorrow.

My intend is to check one particular point at the step "color"; to get cie and saturation charts with different values in order to draw the response curves. Then for a given "color" adjustment, looking at the response to tint and saturation.

There are so many interactions...a Taguchi design of experiments would be great!


Mr JVC, what does "THX Certified" really involve?

Hi LeDahu,


Thanks very much for the feedback. One because it's nice to know that my efforts were useful to you, second because with Christmas I didn't have time to run tests at less than 100% sturation and your data in the saturation charts before and after calibration doesn't look encourraging (but is nevertheless very useful!). It looks like as soon as you try to correct the gamut I was working with 100% patterns), everythingis all over the place and actually only tracks at the level you have calibrated. I'll run tests today with my own settings if I can, using the files kindly provided by Tom and will report.


Let's not dismiss the THX mode too early, if it gets better re greyscale after a few hundred hours, it may become our fallback mode if it's then only mode to be accurate at all saturation levels...


Have a good test session today, hope you'll improve your greyscale, and also be careful if you change the contrast settings from it's defautl, it is likely to adversely affect the gamut (at 100%!).
 
#266 ·

Quote:
Originally Posted by GlenC /forum/post/15380434


It will never happen with the RS series. JVC Professional markets their units to professional installers. The authorized resellers/installers are supposed to know how to do the setup and provide support to their customers..... The Consumer HD series, well we all know how the retail market supports their customers. Go to your local BB and try to see if they know what CMS is.

Are you saying that professionals are able to get everything right? Any way, JVC does provide a manual so it would seem more than proper that also advanced topic would be covered. I guess a couple pages on a website somewhere could do the trick. This of course would require some interest in aftermarketing from JVC.
 
#267 ·

Quote:
Originally Posted by karrih /forum/post/15381663


Are you saying that professionals are able to get everything right? Any way, JVC does provide a manual so it would seem more than proper that also advanced topic would be covered. I guess a couple pages on a website somewhere could do the trick. This of course would require some interest in aftermarketing from JVC.

Hi,


for laughing, JVC doesn't give information on the latest firmware on the HD1/RS1 (i.e. : 064) so more details on the CMS, it must be a dream.


.....................sorry
 
#268 ·

Quote:
Originally Posted by lovingdvd /forum/post/15381088


Thanks Lawguy. Wow these numbers are not very encouraging - seem to be over the place. How do the colors look as you move up %-wise in the patterns? Can you see a very visible shift in the color or does it just become brighter?


For instance the plot of red at 75% with x of .528 is grossly undersaturated. This color would be more of a pink/magenta. Does the pattern look like that (hope not!) or just a less bright version of red at 100%?


For this data did you calibrate at 100% levels or 75% levels. I wonder if the results would be different if done the opposite.


Also you published the xy values only. I think Tom was mainly after the Y portion (of the xyY) which was not posted. The idea was to see if Y tracked properly and did not clip - and that question remains. Can you please post the Y to go along with the xy data you provided for the 25-100% levels?


But in the meantime you may have highlighted even a more significant issue... I'm hoping this is just a measurement or operator error of some sort. Hart to imagine the color could be this far off as the Y % changes. I BRIEFLY played around with the CMS to dial in a quick gamut I was happy with, and in my very limited testing I didn't see any gross errors so I am hopeful this is not an actual issue (because such errors would be quite easy to spot - i.e. something magenta instead of red).

Those measurements are of saturation (25% saturation, etc.) so the lower numbers hould look unsatuated. I misunderstood what Tom was looking for. I'll do what he asked now that I have access to the proper patterns.
 
#269 ·
All right. Bad news confirmed.


Using Tom's patterns (which, by the way measure differently than the AVS patterns (which is right?)) I have confirmed that things go decidely pear shaped when moving from 100% colors to 75% or under.


It is not as if the results track a little bit off. They are WAY off with some of the colors.


This is very disappointing.


I also confirm that the THX settings do not realy vary from 100% to 75%. The THX settings generally are pretty close, btw.


I recommend using the THX settings, even though you can't adjust gamma or anything else for that matter.
 
#270 ·

Quote:
Originally Posted by Lawguy /forum/post/15382095


All right. Bad news confirmed.


Using Tom's patterns (which, by the way measure differently than the AVS patterns (which is right?)) I have confirmed that things go decidely pear shaped when moving from 100% colors to 75% or under.


It is not as if the results track a little bit off. They are WAY off with some of the colors.


This is very disappointing.


I also confirm that the THX settings do not realy vary from 100% to 75%. The THX settings generally are pretty close, btw.


I recommend using the THX settings, even though you can't adjust gamma or anything else for that matter.

Thanks for doing this Lawguy, it's just the info I'm looking for before making my final purchase decision as the CMS is the primary reason for the change. Your numbers appear to be consistent with the impressions which I interpreted as color under saturation/offness with CMS engaged reported by at least four members up to this point, DarinP2 and Kris Deering being two of them.


After plotting your numbers I would think the image would take on an overall purplish color as all the reds and blues below 100% saturation steer in that direction, is the what you're seeing on the screen? Unfortunately the THX setting, if anywhere near accurate out of the box, might be useful for purposes of relative accuracy for about two to three hundred hours, after that it won't serve much purpose. I'm thinking there must be something in the service menu to allow, at least THX qualified, calibrators to adjust settings to maintain THX criteria as the lamp and PJ age otherwise "THX Approved" serves imo no material purpose in the projector arena aside from a marketing $tamp of approval.
 
#271 ·
This is totally going in the wrong direction. Here is a hint: Start from -25 saturation and do the proper CMS adjustment, that will give you a much better result. Later you have to compensate for the saturation loss in the source. I don't know why JVC did this crazy design, but this was the only approach I could get good results, howver the results are much better than with the THX settings.


No purple look or whatsoever.


The HD750/RS20 is a major step forward, don't get confused.
 
#272 ·

Quote:
Originally Posted by Lawguy /forum/post/15382095


All right. Bad news confirmed.


Using Tom's patterns (which, by the way measure differently than the AVS patterns (which is right?)) I have confirmed that things go decidely pear shaped when moving from 100% colors to 75% or under.


It is not as if the results track a little bit off. They are WAY off with some of the colors.


This is very disappointing.


I also confirm that the THX settings do not realy vary from 100% to 75%. The THX settings generally are pretty close, btw.


I recommend using the THX settings, even though you can't adjust gamma or anything else for that matter.

1) Is this with you calibrating the CMS at 100% or at 75%? Which ever way it is, have you tried it the other way? For instance, say you calibrated at 100%. Perhaps if you calibrate at 75%, then maybe things will hold up much better when going up to 100% and down from 75%.


2) Have you displayed 50% red (for example), and then a 75% and 100% red sequentially, and when doing so can you see it shift in color? If things are ok then it should just get brighter but not actually shift in tone. Can you try this and let us know?


3) To me THX it is not an acceptable workaround for a number of big reasons. A big draw of the RS20 to me is the CMS controls, and from


4) Can you display a color saturation scales pattern? Do the colors look consistent?


5) Can you please post some CIE charts that show a few examples of the poor readings?


6) I am not totally discouraged by these reports. I did have a few moments to dial in the CMS and then do some very brief testing. In this brief testing I did not notice anything significantly wrong. If I'm reading some of this data correctly, then at some % levels red would look magenta (as just one example) - that's going to be hard to miss and I didn't see this type of issue. But as I said it was very brief and limited testing. The only thing that really drew attention to itself post-CMS calibration was that the overall picture level seemed to get brighter (almost like the gamma had gone down). But I didn't have time to go back and measure everything to see what was going on.
 
#273 ·
I can confirm what Lawguy found about 100IRE vs 75IRE measurements, this is exactly why I badly want the THX mode to be calibratable, and I still don't understand how THX can charge calibrators for calibration education, and at the same time allow THX certified products that are non-calibratable in THX mode.


BTW, I think a lot of people won't quite get the difference between a 25/50/75/100% saturation and a 25/50/75/100% brightness RGBCMY measurement... Perhaps someone can explain better than me what the difference is... And I believe that one could be correct while the other is off. Both should be correct for absolutely bullet-proof accurate color. I'm not sure any display in the world actually achieves that though, even within studios, so while it never hurts to know the goal, we shouldn't start bashing displays that don't achieve that too much.


When I get back to my own PC, I'll look for the measurements from the THX mode. I believe I god dE94 numbers of less than 2 for both RGBCMY and greyscale, in THX mode off-screen from a ST130. The fact that the CMS isn't as good as it should be, does not change my view that the RS20 is a significant upgrade from an RS2.
 
#274 ·
Otto, can you try my approach starting with something like -25 saturation and calibrate from there (including later compensation for the saturation loss by increasing the saturation level of the source)?!
 
#275 ·

Quote:
Originally Posted by clehner /forum/post/15382497


This is totally going in the wrong direction. Here is a hint: Start from -25 saturation and do the proper CMS adjustment, that will give you a much better result. Later you have to compensate for the saturation loss in the source. I don't know why JVC did this crazy design, but this was the only approach I could get good results, howver the results are much better than with the THX settings.


No purple look or whatsoever.


The HD750/RS20 is a major step forward, don't get confused.

From what I remember, starting with a large negative number for overall saturation (Color control) makes it so that you cannot raise brightness for Blue high enough with the CMS controls (leaves you way short). I first tried with -30 or -25 (can't recall) and that's what happened, so I had to use a higher value for Color (I think it was -17).
 
#276 ·

Quote:
Originally Posted by Otto J /forum/post/15382519


I can confirm what Lawguy found about 100IRE vs 75IRE measurements, this is exactly why I badly want the THX mode to be calibratable, and I still don't understand how THX can charge calibrators for calibration education, and at the same time allow THX certified products that are non-calibratable in THX mode.


BTW, I think a lot of people won't quite get the difference between a 25/50/75/100% saturation and a 25/50/75/100% brightness RGBCMY measurement... Perhaps someone can explain better than me what the difference is... And I believe that one could be correct while the other is off. Both should be correct for absolutely bullet-proof accurate color. I'm not sure any display in the world actually achieves that though, even within studios, so while it never hurts to know the goal, we shouldn't start bashing displays that don't achieve that too much.


When I get back to my own PC, I'll look for the measurements from the THX mode. I believe I god dE94 numbers of less than 2 for both RGBCMY and greyscale, in THX mode off-screen from a ST130. The fact that the CMS isn't as good as it should be, does not change my view that the RS20 is a significant upgrade from an RS2.

This raises an interesting question. Are you guys reporting these measurements based on patterns that use lower *saturation* or patterns that use a lower % level (i.e. 75% brightness vs 100%)?
 
#277 ·

Quote:
Originally Posted by lovingdvd /forum/post/15382554


cannot raise brightness for Blue high enough with the CMS controls (leaves you way short).

Hm, Blue never was a problem for me, only Red and esp. Green. Where did you end up with Blue? Oversaturated no matter what?


@Otto J: The difference between saturation and brightness can probably best explained using the three dimension of the CIE chart.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top