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-   -   "TrueColor" Scene File Tests (https://www.dvinfo.net/forum/jvc-gy-hd-series-camera-systems/66305-truecolor-scene-file-tests.html)

Earl Thurston April 30th, 2006 03:30 PM

"TrueColor" Scene File Tests
 
I had the opportunity last weekend to try out Paolo Ciccone's excellent "TrueColor" scene file for the HD100. I had previously been testing a file I named "WIDELAT2," based on one of Tim Dashwood's scene files, and wanted to see how they compared. I also tried a third variation, which combined the "TrueColor" matrix settings with Tim's wide latitude settings.

The TrueColor variations certainly display much more vibrant and natural colour than the HD100's un-adjusted matrix. Highly recommended. But I also noticed that the third (combined) variation, while looking a slight bit more washed, also exhibited more detail in the shadows.

Paolo measured his latitude at about 7 stops, but I think that the combined setting may eke out just a little bit more.

Here are some comparisons for one particular example scene (I did about 10 scenes, which I will post on my site a bit later):

Original "WIDELAT2" settings:
http://ethur.stargate.ca/neopics/QEPark_07_widelat2.jpg

Paolo Ciccone's "TrueColor" scene file:
http://ethur.stargate.ca/neopics/QEPark_07_truclrpc.jpg

Combined "TrueColor" with "widelat" variations:
http://ethur.stargate.ca/neopics/QEPark_07_truclret.jpg

Crop showing difference in the shadows:
http://ethur.stargate.ca/neopics/QEP...r_compared.jpg

And for reference, here are the settings:

WIDELAT2
Master Black -1
Detail MIN
Black STRETCH3
White Clip 108%
Knee MANUAL
Level 80%
Cinelike CINELIKE
Color Matrix OFF
Adjust (all NORMAL)
Gamma STANDARD
Level NORMAL
Color Gain NORMAL

TRUCLRPC (Paolo Ciccone)
Master Black -2
Detail MIN
Black STRETCH1
White Clip 108%
Knee MANUAL
Level 90%
Cinelike OFF
Color Matrix STANDARD
Adjust
- R Gain 3
- R Rotation 4
- G Gain 2
- G Rotation NORMAL
- B Gain 3
- B Rotation -3
Gamma CINELIKE
Level -1
Color Gain NORMAL

TRUCLRET ("widelat" variation)
Master Black -1
Detail MIN
Black STRETCH3
White Clip 108%
Knee MANUAL
Level 80%
Cinelike OFF
Color Matrix STANDARD
Adjust
- R Gain 3
- R Rotation 4
- G Gain 2
- G Rotation NORMAL
- B Gain 3
- B Rotation -3
Gamma CINELIKE
Level NORMAL
Color Gain NORMAL

Earl Thurston April 30th, 2006 07:12 PM

(By the way, if anyone read the above posting before 6:10pm tonight [April 30], I had some of the settings backwards. They've been corrected above.)

Soroush Shahrokni April 30th, 2006 07:43 PM

Earl, the links doesnt work!

Chad Terpstra April 30th, 2006 08:33 PM

Quote:

Originally Posted by Soroush Shahrokni
Earl, the links doesnt work!

Indeed. -Thrilled to see them, but the links don't work.

Earl Thurston May 1st, 2006 10:32 AM

Please send me a screen shot of the exact error message you are getting. The links work fine for me, so I need to know more in order to fix it.

Marty Hudzik May 1st, 2006 10:36 AM

Quote:

Originally Posted by Earl Thurston
Please send me a screen shot of the exact error message you are getting. The links work fine for me, so I need to know more in order to fix it.

I'm getting a basic "page cannot be displayed" message. Very generic.

Earl Thurston May 1st, 2006 10:43 AM

Hi again. My tech guys think they found the problem. Please try again and let me know if the links are working now. If not, I'll move them to a different server.

(I work for an ISP, BTW.)

Chad Terpstra May 1st, 2006 11:04 AM

Thanks for posting these, Earl. I was wondering how one scene might be rendered differently with different settings. I personally much prefer having the widest latitude possible, so I'm with you on the combination of the two. The native True color version seems to crush the blacks a touch (or at least doesn't see into them). I prefer to bring the blacks down in post if need be.

Very good study with positive results.

Soroush Shahrokni May 1st, 2006 02:48 PM

Great job Earl, thanks for posting this, I liked your combo (TRUE/WIDE) setting alot, best of both I have to say!

Stephan Ahonen May 1st, 2006 07:56 PM

I like your variation, the original Truecolor looks a tad too saturated and contrasty, stretching the blacks more helped quite a bit.

Paolo Ciccone May 2nd, 2006 01:59 AM

Hi Earl.

It's 12:57am after a full day spent tweaking the Truecolor config on the set of 3 commercials and I have some more information about color matrix. This shoot gives us the oppurtunity to test the colors with good monitoring gear and the set has a lot of good saturated colors. Long story short, here is TrueColor v.3, for your testing pleasure ;)

Set Master Black to Normal (originally -2), no black stretch. This, IMHO, gives you more detail in the dark areas without affecting the midtones. If you really need to, use the lowest stretch but I wouldn't do it with controlloed lighting, the dramatic effect, without stretch, is stronger with good definition in the dark areas. Also, I had reports of people been able to affect those dark tones in post, a confirmation that TrueColor preserves the information even when, at first, it seems that parts of the picture are too dark.

Set Blue Gain to 1 (originally 3). The Blue gain will actually shift the red toward Magenta a little bit. It's a good combination if the camera seems to be too "red happy".
Dropping the blue to lower value will affetct the skin tones too much, a value of 1 or 2 seems to be a great adjustment to bring the reds a little more "under control" without sacrifice.
I'll be interested to know the Forum's opinions on this.

Earl Thurston May 2nd, 2006 10:31 AM

Quote:

Originally Posted by Paolo Ciccone
Set Blue Gain to 1 (originally 3). The Blue gain will actually shift the red toward Magenta a little bit. It's a good combination if the camera seems to be too "red happy".

Thanks for the update Paolo (and all the initial hard work as well!) It almost seems counter-intuitive that lowering the blue would make the red go more magenta. You'd think it should be the other way around (i.e. more blue = more magenta). I'll have to give it a try.

By the way, "red happy" seems to be the only major concern from people using the "TrueColor" file. Since red gain is set to 3, what have you found happens/goes wrong when that is lowered to 1 or 2?

Stephen L. Noe May 2nd, 2006 01:11 PM

Quote:

Originally Posted by Earl Thurston
(By the way, if anyone read the above posting before 6:10pm tonight [April 30], I had some of the settings backwards. They've been corrected above.)

I though you were going to write something like
"if anyone read the above posting before 6:10pm tonight" You get a prize.

Earl Thurston May 2nd, 2006 01:36 PM

Quote:

Originally Posted by Stephen L. Noe
I though you were going to write something like
"if anyone read the above posting before 6:10pm tonight" You get a prize.

Nah, for that I would've hidden a secret message in a pixel.

Steve Mullen May 2nd, 2006 02:44 PM

Quote:

Originally Posted by Earl Thurston
By the way, "red happy" seems to be the only major concern from people using the "TrueColor" file. Since red gain is set to 3, what have you found happens/goes wrong when that is lowered to 1 or 2?

Perhaps the name "True..." creates a naming problem.

I watch almost nothing but HD and it's clear that many productions, like the 2005 Grammies, have reds far more intense than anything seen in NTSC video. It looks very much like the HiVision I was seeing in Tokyo in the late `80's that I called "Hyper-Real."

So rather than modify the setting, I'd simply rename it as "HyperColor." It will be great at 60p!

I too wonder why one couldn't simply lower the R to 1 to get "TrueColor."

And, you are correct, lowering B should not move toward Mg but increase yellow.


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