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Old 13th October 2011, 11:57   #10085  |  Link
nand chan
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Join Date: Jul 2011
Location: BW, Germany
Posts: 380
Quote:
Originally Posted by THX-UltraII View Post
I just had contact with the ISF professional again and he told me that a ICC profile is not made by with the standard calibration my JVC got. A ICC profile only is made when running content from a HTPC which is what I do of course

Will he need to do a re-calibration for my pj for the best result?
He will not have to re-do your calibration. Profiling is an additional step.

Quote:
Do you only play with rendering programs, video editing for BT605 and rec709bt?
If you ONLY play movies or games than the calibration as I did it is correct. For a ICC calibration you pay € 250,- extra, and again, this is only done for people who play with blackmagic or AJA cards.
For a HTPC it is normal to make a standard ICC profile and calibrate on that profile, otherwise every other source you will connect to your display device other than your HTPC will not be correct. A ICC profile is a extra profile and is only beeing used in systems with a ''locked'' hardware system. And again, only for special purposes, not for HTPC usage. I also will have to make the profile with two analysers, one for the ICC profile (auto process via HTPC) and after that a calibration with the spectrum analyser.
It doesn't matter whether he calibrates to BT.709 or not, even after calibration he can still provide an ICC profile so you can smooth out all of the calibration inaccuracies, and do crazy stuff like provide a 134217728-entry 3D LUT for the absolute best results. I highly, highly doubt that your projector has a 512x512x512 LUT, it's probably more like 16x16x16.

Quote:
You have to read carefully. Do you have a blackmagic card or AJA? I gave you a perfect calibration, the signal that is send out by your PC is 100% according to the standard, gives you a D6500 greyscale with a 2.3 gamma (as close as possible) and a REC709 colorspace.
As I explained before a ICC profile if you run colormanaged software like a renderer, final cut pro in combination with a AJA or blackmagic card of if you use another very specific setup. For normal HT usage, as you do (watching movies) I gave you the correct calibration.
It should not matter whether you use an AJA or blackmagic card - the point here is that the PC tries its “best” to get a D65/2.3/BT709 signal, and the projector tries its “best” to display that. But no matter how good you get this, the projector will usually always be the weak link, since it'll never be a perfect D65/2.3/BT709 (unless your projector has hundreds of megabytes of memory for the calibration ).

The point here is that you should get the projector as close as possible to BT.709 (he's done this), then *profile* it so you have a detailed report of all of the inaccuracies. You should do this over at least 2000 sample patches, but I'd recommend more. An optimal profiling should probably have been done overnight, as they can take many hours at several thousand samples.

Then, you can use your very, very powerful (compared to the projector) HTPC to adjust for all of the tiny little differences. You'll probably be able to cut the delta E in half that way. I doubt you'll see a difference with the eye, but better is always better, right?


Quote:
ICC profiles are for HTPC usage in fact not needed. You just have to have a correct D6500, gamma 2.3 and REC709 calibration. You DO use a ICC profile by the way, but that s 'generic' standard ICC profile. Look in your projector settings and you will see this.
Let me be clear again:
If you use ICC we are talking about setups that work with AJA or blackmagic cards or a very specific colormanaged workflow where you convert from 1 colorspace to another, THERE IS NO HTPC SOLUTION THAT CAN DO THIS. What you do is just play a dvd or videofile and for this is absolutely no ICC profile needed
They're not needed, but they're still useful. A “correct” D6500 / gamma 2.3 / REC709 calibration is not always as “correct” as one wants it to be. This is why I spend up to 10 hours generating massive charts for my playback device. Even those are not perfect, usually because my monitor is limited to 10 bit precision.

Quote:
or a very specific colormanaged workflow where you convert from 1 colorspace to another, THERE IS NO HTPC SOLUTION THAT CAN DO THIS
Tell him this is plain WRONG. madVR is perfectly capable of doing this. That's the whole reason for the ordeal. We *CAN* convert color spaces ourselves, and we do know what we are doing, and have complex software for the task.

Quote:
Originally Posted by THX-UltraII View Post
And here is my calibration report.

ps. Rename the .txt to .xls to see the report!
Upload your attachment somewhere else, getting them approved on doom9 can take quite a while.
__________________
Forget about my old .3dlut stuff, just use mpv if you want accurate color management

Last edited by nand chan; 13th October 2011 at 11:59.
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