Color Profiles and White Balance at DVinfo.net

Alex Raskin · April 26th, 2010, 06:39 PM

I missed that day in the video kindergarten, so please be gentle OK :)

Say, shouldn't I use SiliconDVR's LUTs to save color profiles for each scene?

That would ease color correction in post, I gather.

Plus, it probably will make it easier to match footage shot on different cams... or with different lenses... or all the same gear, but the location lighting changed.... etc.

And if yes, then what test charts should be used?

Will this chart work?

Alex Raskin · April 26th, 2010, 10:23 PM

Found this, which I think is very informative for the color correction "savants" like me:

YouTube - Robert Goodman on DSC Labs CamAlign Charts

And it would appear that the most economical but still good enough version of the DSC chart is this FrontBox:

DSC Labs | FrontBox Pro Test Chart | FBP | B&H Photo Video

Did I get it right?

And... what would be the correct workflow for using the charts with SI-2K?

Bob Hart · April 27th, 2010, 08:40 AM

Alex.

Take this as my personal preferences only, not the gospel of the SI2K.

I usually shoot with the "default" look selected. If I want a quick edit-assembly, I select in the "default" look and trim on that in post. I trust the builders to have made the best call on what the "default" look should be.

If I want to go more filmic and get the most out of the latitutude, then it seems it may be best to grade off the raw image.

The in-camera looks as I understand them are more of a pre-visualisation tool. None of the looks are as they say "baked in" to the camera recorded image.

I also have arrived at the preference of using the fixed white-balance settings, 5600K and 3200K.

I don't know enough about this craft of colormetric charts, camera calibration and edit suite monitor calibration to advise you furthur except to suggest a shot of a dumonde chart at beginning of the first of a series of the same shot at the subject's position can't hurt. If there is a lighting trim, then another shot of the chart at the subject's position.

A chart would also be shot for each white-balance change or selection and for each lens change unless the lenses are a matched set of good cine primes.

Having these references apparently makes the colorist's job of arriving at a baseline for all shots to grade from a bit easier.

When we shot the Sonic Sessions concerts in Fremantle, I talked them into having a shot by each camera of a dumonde chart in the same position on the stage to enable the camera images to be matched.

On that shoot there was a SI2K, two RED Ones, two JVC GY-HD100s and a Sony PMW-EX1. There was a mixed bag of non-cinema lenses on the digital cinema cameras each with its own color bias or maybe not. As we are likely to be using un-matched sets of prime lenses or even a selection of different lenses and brands the chart seems to me to be a good idea.

Alex Raskin · April 27th, 2010, 10:03 AM

Yes, Default look for previz on location is fine, but I did bump into situations where lens changes on the same cam introduce obviously different color reproduction, that needs to be corrected in post. And god forbid there's a second cam of different type - then how do I match the footage for intercutting in post?

And I do 2-cam shoots with SI-2K and Canon 7D as second video camera, a lot.

Surely DuMonde would be fine, but I cannot afford over $1K cost of it. So it'd be cool to hear from someone using FrontBox Pro - made by the same company DSC...

April 26th, 2010, 06:39 PM	#1
Alex Raskin Trustee Join Date: Sep 2003 Posts: 1,435	Color Profiles and White Balance I missed that day in the video kindergarten, so please be gentle OK :) Say, shouldn't I use SiliconDVR's LUTs to save color profiles for each scene? That would ease color correction in post, I gather. Plus, it probably will make it easier to match footage shot on different cams... or with different lenses... or all the same gear, but the location lighting changed.... etc. And if yes, then what test charts should be used? Will this chart work?

April 27th, 2010, 08:40 AM	#3
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Alex. Take this as my personal preferences only, not the gospel of the SI2K. I usually shoot with the "default" look selected. If I want a quick edit-assembly, I select in the "default" look and trim on that in post. I trust the builders to have made the best call on what the "default" look should be. If I want to go more filmic and get the most out of the latitutude, then it seems it may be best to grade off the raw image. The in-camera looks as I understand them are more of a pre-visualisation tool. None of the looks are as they say "baked in" to the camera recorded image. I also have arrived at the preference of using the fixed white-balance settings, 5600K and 3200K. I don't know enough about this craft of colormetric charts, camera calibration and edit suite monitor calibration to advise you furthur except to suggest a shot of a dumonde chart at beginning of the first of a series of the same shot at the subject's position can't hurt. If there is a lighting trim, then another shot of the chart at the subject's position. A chart would also be shot for each white-balance change or selection and for each lens change unless the lenses are a matched set of good cine primes. Having these references apparently makes the colorist's job of arriving at a baseline for all shots to grade from a bit easier. When we shot the Sonic Sessions concerts in Fremantle, I talked them into having a shot by each camera of a dumonde chart in the same position on the stage to enable the camera images to be matched. On that shoot there was a SI2K, two RED Ones, two JVC GY-HD100s and a Sony PMW-EX1. There was a mixed bag of non-cinema lenses on the digital cinema cameras each with its own color bias or maybe not. As we are likely to be using un-matched sets of prime lenses or even a selection of different lenses and brands the chart seems to me to be a good idea. Last edited by Bob Hart; April 27th, 2010 at 08:43 AM. Reason: error

April 26th, 2010, 10:23 PM	#2
Alex Raskin Trustee Join Date: Sep 2003 Posts: 1,435	Found this, which I think is very informative for the color correction "savants" like me: YouTube - Robert Goodman on DSC Labs CamAlign Charts And it would appear that the most economical but still good enough version of the DSC chart is this FrontBox: DSC Labs \| FrontBox Pro Test Chart \| FBP \| B&H Photo Video Did I get it right? And... what would be the correct workflow for using the charts with SI-2K?

April 27th, 2010, 10:03 AM	#4
Alex Raskin Trustee Join Date: Sep 2003 Posts: 1,435	Yes, Default look for previz on location is fine, but I did bump into situations where lens changes on the same cam introduce obviously different color reproduction, that needs to be corrected in post. And god forbid there's a second cam of different type - then how do I match the footage for intercutting in post? And I do 2-cam shoots with SI-2K and Canon 7D as second video camera, a lot. Surely DuMonde would be fine, but I cannot afford over $1K cost of it. So it'd be cool to hear from someone using FrontBox Pro - made by the same company DSC...