Official JVC RS20 / HD750 Calibration and CMS thread (NEW FIRMWARE V1.1) - Page 5 - AVS Forum
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post #121 of 1634 Old 04-29-2009, 11:04 AM - Thread Starter
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First of all, thanks for all the help regarding my meters dilemma.

I have solved it by opening a second i1pro that has been sent to me by mistake and that hasn't been collected after 3 weeks and many emails.

It returns exactly the same values as the one I have.

As my eyes also tell me that the i1pro is right, and as the greyscale it returns is superior (ie more neutral) to the greyscale returned by the d2, which is slightly on the warm side, I have decided to put the matter to rest and declare the i1pro the reference and the d2 the off one, which is logical.

The consequence is that THX, at least on my PJ, is seriously undersaturated, but that also tallies as you all know, with my experience of THX (again, on my PJ).

I have put my new lamp back in to clarify that this was not an issue either, so this calibration is done in exactly the same condition as my first attempt (new lamp, i1pro). The main thing that's gone is the human error (too much brightess on green, which induced the slight lack of linearity in my first attempt).

So I have redone a greyscale (just color temp, no work on gamma yet, apart from selecting a 2.3 custom default) using the i1pro. I reckon the greyscale is now flat enough for not being an issue (I made sure I was as close as possible to D65 at 100 IRE).

I have then recalibrated the gamut at 75%, as I realised that it needed much less correction at this level of stimulus to get an almost perfect gamut, and the gamut at 100% is just as good.

I have also run the saturation measures for Stereodaman to dissect.

The conclusion is that the new firmware gets a clean bill of health.

It's as linear as one can wish (I don't think anyone has reported a consumer product with such a good linearity).

And it's as straightforward to use as one could wish, as it is now working as intended. There is very little interaction between the controls, which are now reasonably separate.

Based on my experience, I would just warn about pushing brightness too high, which I did by mistake in my first attempt and which generated the initial slight lack of linearity on green, and to calibrate at 75% rather than 100% as the results are at least as good, with less correction applied which I assume is better.

Here are my settings for those who are not entirely put off by the meter dilemna:

Custom color temp (new lamp)
Gain R = -30
Gain G = 0
Gain B=-58
Offset R=0
Offset G=-4
Offset B=0

CMS (HSB)
R= -4 -22 3
Y=6 -46 37
G=-11 -43 31
C=-3 -51 39
B=30 0 -7
M=1 0 -5

I wish I had posted this as my first attempt, and hope you'll forgive me for the confusion, but hopefully this sets the record straight.

Note: the greyscale and saturation data is in the 3rd attempt HCFR file, as this was my main calibration. The 100% just shows what you get at 100% stimulus, and only the gamut info is relevant in this file.
LL
LL
LL
LL

 

3rd attempt HCFR files.zip 17.83203125k . file
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post #122 of 1634 Old 04-29-2009, 11:06 AM - Thread Starter
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Here are the results at 100% stimulus
LL
LL
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post #123 of 1634 Old 04-29-2009, 11:07 AM
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Quote:
Originally Posted by lovingdvd View Post

I'll defer to Tom and others for the formal explanation, but the bottom line is that if your grayscale is not flat, your colors will not be right, period (particularly hue).

No this has nothing to do with your meters but rather - a flat grayscale is mandatory for proper colors.

A poor grayscale will effect the hue of the secondaries, but it wouldn't have any substantial effect on the primaries. Since Manni's main problem is with the green primary, I don't think that this is the problem.

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post #124 of 1634 Old 04-29-2009, 11:16 AM
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Manni, Did the change in lamp affect the CMS much?
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post #125 of 1634 Old 04-29-2009, 11:16 AM
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Quote:
Originally Posted by GlenC View Post

As Craig and others mentioned before, many of the non-expensive meters can measure gray scale with some accuracy but really go off when trying to measure primaries.

This one of these calibration myths that just refuses to die.

Try the following: measure white and red with a reference spectro and then measure white and red with a decent low-cost colorimeter--the Chroma 5 or even D2. I'll bet that you'll find that the colorimeter's reading of red is MORE accurate than its reading of white.

Colorimeters do have a problem with green and sometimes yellow and/or cyan, but in my experience they generally do better with red, magenta and blue than they do with white. On average they are no more or less accurate with color than they are with white.

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post #126 of 1634 Old 04-29-2009, 11:19 AM - Thread Starter
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Quote:
Originally Posted by JeffY View Post

Manni, Did the change in lamp affect the CMS much?

No, not massively. It had more impact on the greyscale.
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post #127 of 1634 Old 04-29-2009, 11:23 AM
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Quote:
Originally Posted by Manni01 View Post

Based on my experience, I would just warn about pushing brightness too high, which I did by mistake in my first attempt and which generated the initial slight lack of linearity on green, and to calibrate at 75% rather than 100% as the results are at least as good, with less correction applied which I assume is better.

In what circumstances do you think someone may accidentially drive green brightness too high? I ask because you also mentioned that the controls are now very responsive and do what you'd expect them to do - so I'm trying to understand what conditions would cause someone to drive green too much. Unless it is just the case of a bad/inaccurate meter - which if I am following along you are basically saying that if your meter isn't right then you could wind up driving green too much?

I just might have to re-prioritize some work so I can get some play time in!
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post #128 of 1634 Old 04-29-2009, 11:30 AM - Thread Starter
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Quote:
Originally Posted by lovingdvd View Post

In what circumstances do you think someone may accidentially drive green brightness too high? I ask because you also mentioned that the controls are now very responsive and do what you'd expect them to do - so I'm trying to understand what conditions would cause someone to drive green too much. Unless it is just the case of a bad/inaccurate meter - which if I am following along you are basically saying that if your meter isn't right then you could wind up driving green too much?

I just might have to re-prioritize some work so I can get some play time in!

I did yesterday's calibration very quickly, and I simply made a human error when setting green's brightness. The controls have always worked as intended, it's just that yesterday, I found a lack of linearity in my first attempt and instead of questionning my abilities, and double check my calibration or redo it, I questioned the new firmware.

Bad mistake, lesson learnt.

But by all means, come and save the world!

As I said, we can't wait for you to join the party...
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post #129 of 1634 Old 04-29-2009, 11:38 AM - Thread Starter
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Quote:
Originally Posted by lovingdvd View Post

In what circumstances do you think someone may accidentially drive green brightness too high? I ask because you also mentioned that the controls are now very responsive and do what you'd expect them to do - so I'm trying to understand what conditions would cause someone to drive green too much. Unless it is just the case of a bad/inaccurate meter - which if I am following along you are basically saying that if your meter isn't right then you could wind up driving green too much?

I just might have to re-prioritize some work so I can get some play time in!

Oh and just one more thing, I don't know how you calibrate, but I use HCFR along with Stereodaman's excellent excel spreadsheet to calculate my brightness target for each color, based on the Y value for white at 100% (if there is a way to get this automatically from HCFR, I haven't found it and it would be a #1 request for the feature list for the next version).

Although the spreadsheet is great, navigating between Excel and HCFR may have induced the error, as it is a manual process (involving me!).

If you look at brightness for green, it says 44 in my attempt one, versus 31 in my last attempt.

If I have a bit of time later, I will put it back to 44, and check if my linearity issue is back.
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post #130 of 1634 Old 04-29-2009, 11:43 AM
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Quote:
Originally Posted by Manni01 View Post

No, not massively. It had more impact on the greyscale.

Thanks, that is what I expected.
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post #131 of 1634 Old 04-29-2009, 12:01 PM
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Quote:
Originally Posted by Manni01 View Post

Oh and just one more thing, I don't know how you calibrate, but I use HCFR along with Stereodaman's excellent excel spreadsheet to calculate my brightness target for each color, based on the Y value for white at 100% (if there is a way to get this automatically from HCFR, I haven't found it and it would be a #1 request for the feature list for the next version).

Yea it would be nice if HCFR would show this. IIRC its something I requested to their developers a while back.

I use Greg's excellent free app (can't find a link to it tho). Essentially you put in your #s for white and based on the gamut you select such as Rec 709 (or a custom gamut) it shows you the target x y and Y for RGBCMY.
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post #132 of 1634 Old 04-29-2009, 12:03 PM - Thread Starter
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Quote:
Originally Posted by lovingdvd View Post

Yea it would be nice if HCFR would show this. IIRC its something I requested to their developers a while back.

I use Greg's excellent free app (can't find a link to it tho). Essentially you put in your #s for white and based on the gamut you select such as Rec 709 (or a custom gamut) it shows you the target x y and Y for RGBCMY.

Yes, this is what Strereodaman's spreadsheet does, but it also gives you targets for gamma, saturations, prim/sec at 75% or 100% stim etc...

Here is the link http://www.avsforum.com/avs-vb/showt...7#post15607437.
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post #133 of 1634 Old 04-29-2009, 12:42 PM
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@Manni:I have try your CMS setting and attached you can find the result. Either the difference comes from the meter (i1 LT) or/and the PJ.

It would be great if other user try and measure different CMS settings and post the results. This would help us to find out if we could exchange the CMS settings and where we can expect the difference. From my measurement the Y is the biggest problem.
LL
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post #134 of 1634 Old 04-29-2009, 12:55 PM - Thread Starter
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Quote:
Originally Posted by Shepardos View Post

@Manni:I have try your CMS setting and attached you can find the result. Either the difference comes from the meter (i1 LT) or/and the PJ.

It would be great if other user try and measure different CMS settings and post the results. This would help us to find out if we could exchange the CMS settings and where we can expect the difference. From my measurement the Y is the biggest problem.

Thanks very much for this, but I can only see some of the information on the screenshot (only y and Y). Indeed Y seems much lower for all the colors on your PJ/with your meter. I have no idea why. I can't see the x info on your screenshot, where is green on your gamut with my settings? On rec709, or outside the gamut? Does it look right or oversaturated? And visually, how do my settings look on your PJ?
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post #135 of 1634 Old 04-29-2009, 02:05 PM - Thread Starter
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I have done some first critical viewing with my latest settings, the usual suspects (Wall-E, Cars, Dark Knight, Tropic Thunder).

The only thing I can say is that I have never seen the PJ looking that good.

The i1pro definitely looks like the right reference to use. There is no clipping, an amazing depth to the picture, I checked green in Tropic Thunder and it's definitely not oversaturated, the skin tones in Dark Knight are perfect, the whites are white...

It feels like there was a veil in front of the lens and it's been taken away!

Hope you'll experience the same, but personally, I couldn't be happier.

Hats off to JVC for the upgrade, it performs flawlessly as far as my eyes can see.
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post #136 of 1634 Old 04-29-2009, 03:37 PM
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Manni,

Thanks alot!!! Just ordered a i1pro, software, and a signal generator.......can't wait to start the learning curve.

Rick
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post #137 of 1634 Old 04-29-2009, 03:46 PM - Thread Starter
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Quote:
Originally Posted by Googer View Post

Ah, I've been keeping an eye out for the new firmware and now I see it's out with very positive impressions. I'll be updating my RS20 and recalibrating sometime in the next few days, after which I should be posting my new settings.

Looking forward to it
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post #138 of 1634 Old 04-29-2009, 03:49 PM - Thread Starter
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Originally Posted by RickS View Post

Manni,

Thanks alot!!! Just ordered a i1pro, software, and a signal generator.......can't wait to start the learning curve.

Great, let us know how your i1pro read THX, both 008 and myself would be interested to find out
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post #139 of 1634 Old 04-29-2009, 08:20 PM
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In case there are any Mac users out there, I updated my HD750 with no problems from a MacBook Pro, running Boot Camp/Windows XP. Worked perfectly....


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post #140 of 1634 Old 04-29-2009, 08:51 PM
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Originally Posted by thrang View Post

In case there are any Mac users out there, I updated my HD750 with no problems from a MacBook Pro, running Boot Camp/Windows XP. Worked perfectly....

Thanks for this. Im running a MacBook pro with Parallel/XP and will upgrade tomorrow evening.
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post #141 of 1634 Old 04-29-2009, 10:51 PM
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Thanks for this. Im running a MacBook pro with Parallel/XP and will upgrade tomorrow evening.

FYI
I tried with a MacBookPro running Parallels/Vista (64 bit) and no go! Had to move my vista desktop in the HT to get it done.
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post #142 of 1634 Old 04-30-2009, 12:22 AM - Thread Starter
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Originally Posted by CraigN View Post

FYI
I tried with a MacBookPro running Parallels/Vista (64 bit) and no go! Had to move my vista desktop in the HT to get it done.

This is probably because of Vista 64bits (the driver is for XP/vista 32).
As it seems to be running with boot camp, parallel with XP/Vista32 should work. This is good news for Millerwill...
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post #143 of 1634 Old 04-30-2009, 01:15 AM
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Originally Posted by Shepardos View Post

@Manni:I have try your CMS setting and attached you can find the result. Either the difference comes from the meter (i1 LT) or/and the PJ.

It would be great if other user try and measure different CMS settings and post the results. This would help us to find out if we could exchange the CMS settings and where we can expect the difference. From my measurement the Y is the biggest problem.

I did try Mannis settings as well. Unfortunatetly I didn't save my D2 measurements, but dE was about 4 across and gamut triangle seemed to be shifted to right and below at all primaries. I get similar displacement in THX mode only for green primary. Anyway, I did use it yesterday evening and did not notice any problems. I will need to take a closer look to see if I would prefer it over the tweaked THX mode as it is now, but it could well be. Anyway it could be good starting point if I were to calibrate according to my measurements, so, thanks Manni.
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post #144 of 1634 Old 04-30-2009, 02:04 AM - Thread Starter
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Quote:
Originally Posted by karrih View Post

I did try Mannis settings as well. Unfortunatetly I didn't save my D2 measurements, but dE was about 4 across and gamut triangle seemed to be shifted to right and below at all primaries. I get similar displacement in THX mode only for green primary. Anyway, I did use it yesterday evening and did not notice any problems. I will need to take a closer look to see if I would prefer it over the tweaked THX mode as it is now, but it could well be. Anyway it could be good starting point if I were to calibrate according to my measurements, so, thanks Manni.

Thanks for the feedback Karrih. I guess the way it looks is more important than the way it measures, unless you can use a i1pro or better. There is too much uncertainty with uncertified tristim (they can be really good or a bit off and there is no way to know).
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post #145 of 1634 Old 04-30-2009, 03:23 AM
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Manni. I finished installation of the new firmware late this evening and put in your settings into Custom1. Since I have no metering capability all I can do is to observe the images.

What I found is very interesting indeed:
First, the color of everything I have looked at tonight (many selected Film and TV HD segments used since about January 20th) for the first time are very close to those when using the THX mode. The key difference is similar to what you are reporting.....THX looks slightly less saturated.
There is a pronounced improvement in the behavior of green...gone is the excessive intensity of green colors.
The reds of blood, coke signs and the British telephone booths are much closer to reality.

Second--and I don't think much has been reported about this area... The color decoders are now almost perfect....for the first time. I test the Color decoders with the DVE disk (Color Bars) and the colored supplied filters as outlined by Joe Kane. None of the various "make do" settings we used in the past did well when you looked at the color decoder performance. Now the improvement is very clear and striking.
I would suggest this may be the easiest test to see if the settings you and others may find with instrumentation calibration can really be usefully applied across a wider set of projectors by others on these threads-- with reasonably good results.

Hats off to JVC.
And Manni--a special thanks for your settings.
If my findings are repeated by others..for those of us who currently have no metering capability .. here is a way to bring the color performance of the RS20 way up from we were -- just 1 week ago.

EDIT: 1. I used your third attempt settings. 2. Using filters and DVE I had to make small adjustments to the main Color and Tint controls for both your settings and THX to bring the color decoders into line as I described above.

KT
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post #146 of 1634 Old 04-30-2009, 03:27 AM - Thread Starter
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Quote:
Originally Posted by KTTV Images View Post

Manni. I finished installation of the new firmware late this evening and put in your settings. Since I have no metering capability all I can do is to observe the images.

What I found is very interesting indeed:
First, the color of everything I have looked at tonight (many selected Film and TV HD segments used since about January 20th) for the first time are very close to those when using the THX mode. The key difference is similar to what you are reporting.....THX looks slightly less saturated.
There is a pronounced improvement in the behavior of green...gone is the excessive intensity of green colors.
The reds of blood, coke signs and the British telephone booths are much closer to reality.

Second--and I don't think much has been reported about this area... The color decoders are now almost perfect....for the first time. I test the Color decoders with the DVE disk (Color Bars) and the colored supplied filters as outlined by Joe Kane. None of the various "make do" settings we used in the past did well when you looked at the color decoder performance. Now the improvement is very clear and striking.
I would suggest this may be the easiest test to see if the settings you and others may find with instrumentation calibration can really be usefully applied across a wider set of projectors by others on these threads-- with reasonably good results.

Hats off to JVC.
And Manni--a special thanks for your settings.
If my findings are repeated by others..for those of us who currently have no metering capability .. here is a way to bring the color performance of the RS20 way up from we were -- just 1 week ago.

KT

Hi KT,

Thanks for the detailed feedback, and glad to hear my settings worked that well for you. I know they work for me, and it's good to know I'm not entirely color blind.
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post #147 of 1634 Old 04-30-2009, 03:29 AM
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Quote:
Originally Posted by Manni01 View Post

Oh and just one more thing, I don't know how you calibrate, but I use HCFR along with Stereodaman's excellent excel spreadsheet to calculate my brightness target for each color, based on the Y value for white at 100% (if there is a way to get this automatically from HCFR, I haven't found it and it would be a #1 request for the feature list for the next version).

I'm still relatively new to calibration although I am able to understand and run HCFR. I'm confused by this post, HCFR seems pretty comprehensive to me, why is this extra work necessary? I use HCFR to adjust the colors to fit the CIE curve and that works for me. I have read the thread and looked at the spreadsheet and it seems like Stereomandan is replicating HCFR in Excel.

I'm obviously missing something here. Can someone explain what improvement to the calibration process the spreadsheet gives over HCFR?
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post #148 of 1634 Old 04-30-2009, 03:34 AM - Thread Starter
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Quote:
Originally Posted by deandob View Post

I'm still relatively new to calibration although I am able to understand and run HCFR. I'm confused by this post, HCFR seems pretty comprehensive to me, why is this extra work necessary? I use HCFR to adjust the colors to fit the CIE curve and that works for me. I have read the thread and looked at the spreadsheet and it seems like Stereomandan is replicating HCFR in Excel.

I'm obviously missing something here. Can someone explain what improvement to the calibration process the spreadsheet gives over HCFR?

This is because you are doing what I did when I started, ie look at x,y only and forget to adjust Y (brightness). HCFR shows you how close you are re x,y, but it only gives you a numerical value for Y. If you don't know which target value to use for Y for each color (a percentage or the Y value for white), you end up with a pretty looking CIE chart but the calibration is wrong because brightness (Y) for each color has not been adjusted.
This is what Dan's document gives you: you enter your Y value for white (measured by HCFR after a first run of the primaries/secondaries), and it tells you which target to aim for for the Y of each color. You can then go back to HCFR and adjust the brightness setting for each color until the Y indicated by HCFR reaches the Y calculated by the speadsheet.
You should read Tom's excellent guide here http://www.avsforum.com/avs-vb/showthread.php?t=852536, as CMS work is not really covered in the Dummies guide, and this is why we all fall in the trap
It would be great if HCFR gave a visual clue indicating how far we are from the Y target for each color (which Calman does in some of its layouts), as it would be more straightforward than going to and from the spreadsheet (or Greg's free calculator).

Edit: just found the link to Greg's calculator thread here: http://www.avsforum.com/avs-vb/showthread.php?t=1005676
Fantastic thread, with more info than you need to understand it all...
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post #149 of 1634 Old 04-30-2009, 04:36 AM
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This may be more meter-related than CMS related but is relevant to those who just want to plug in numbers and be done with it.

I entered both of Manni's calibration settings, the D2 and Pro. I measured his settings on my RS20 with my i1LT. Neither was usuable for me but this is what I found.

Manni's Pro figures were extremely close in xy (each color was slightly outside the triangle) but Y was FAR to low across the board. This was very visible in the colors themselves, which looked too drab. dEs were in the 20s.

Manni's D2 figures were not consistent for me. They were, in fact, helter skelter. Some colors were pretty good (dEs of under 10) but others were in the 30s and 40s.

Conclusion? I would like to believe that my i1LT is accurate as compared to Manni's Pro and that Manni's D2 has perhaps seen better days. This seems possible because his Pro settings showed very close xys when measured by my LT. Ys were terribly off but I suspect this may be just lamp to lamp and projector to projector variation. My lamp has over 800 hours on it now and that may account for my very low Ys. Based on this small experiment, I would not recommend just plugging in someone else's CMS numbers. It is just a crap shoot and it is likely that you will be doing more harm than good.

EDIT: I also measured THX mode yesterday and it still looks pretty good. dEs all under 8. I still say that if you don't have a meter or the time or the skills, THX mode is the way to go.

Side note: I don't know if it the new CMS or perhaps my lamp has just settled in but, it took me all of 5 minutes to get a flat grayscale with dEs of 3 or less yesterday.

Affable Nitwit
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post #150 of 1634 Old 04-30-2009, 04:37 AM
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Thanks Manny.

I thought I had the calibration approach licked but I have to go back to school now. Its a bit frustrating as this extra step was not explained in the dummies guide which is what I used to learn.

I think I understand - HCFR gives you the xy colour gamut accuracy but not what the brightness (Y) should be for the color based on the stimulus used (eg. 75%) & adjusted for relative screen brightness. So I assume you adjust the relevant colour brightness control in the CMS to hit the target Y (based on white brightness) when adjusting hue & saturation for each colour?? This seems like an obvious gap in HCFR, but it is free after all!

Is an Eye-One D2 probe good enough to measure white brightness? I have a large screen with the iris almost fully open (high brightness) and the D2 reads about 6-8 fL in HCFR which I thought is a bit too low for a new bulb, yet the image seems bright enough.

Should be pretty easy to add this extra step when calibrating with HCFR. What about the other sheets in this spreadsheet, the gamut, dE & saturation charts? Are these any better than HCFR?

So now along with a more stable lamp (140 hours), a better CMS, including the 'Y' calibration that I missed out when calibrating previously should mean I will get a good improvement post calibration this time around!
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