Quicktime reference files color space

[Miguel "Macgregor" De Olaso]

I come again with this matter since the old post seems to be lost when the server went down.

Now, i have tried to emulate with heavy color correction the colors of the quicktime reference files against the dpxs exported in 709. After hours of trying i simply cant. The color values seems to change along the gamma curve which makes it very difficult to judge by eye.

So has anyone achieved exactly the same look?
Grame, is there a way we could get a precise numeric values of what it is done to the color in the qt reference files?
You said it has an obsolote color space conversion. Whatever it is, i want it. It is how the blues/cyans are handled what i like.

 

[Graeme Nattress]

It's "cameraRGB" in RedAlert, not the newer, preferred, correct white point "CameraRGB2", with the REC709 gamma curve.

I can tell you how the data is generated from the RAW to the Quicktime or Tiff or DPX output, but Quicktime "does it's own thing" from that data, and that's where I loose control.

Graeme

 

[Miguel "Macgregor" De Olaso]

ok i have some data now. This is what happens when exporting with red alert 1.2b.4:

All settings at default/zero/reset. White balance at 5600.
We create a quicktme reference file and a 2k DPX in rec709 color space. They look different.

Now, we apply the following adjustmentes to the DPX, and voilá! Now the look the same (95% accuracy):

color temperature increased from 5600 to 7888º (or add +2288º to whatever you had)
input black 2150
gamma 1,2
color saturation -17%
(done in after fx 16bit per channel project, but it should be the same in most aplications)

 

[Graeme Nattress]

Use the CameraRGB colour space, not REC709 colour space.
Use REC709 gamma curve.

Nothing else should need to be changed - they should look the same.

Graeme

 

[Miguel "Macgregor" De Olaso]

Use the CameraRGB colour space, not REC709 colour space.
Use REC709 gamma curve.

Nothing else should need to be changed - they should look the same.

Graeme

I guess those only are available inthe latest redalert.
When you say use these you mean before creating the qt or when creating the dpx sequence?

 

[Graeme Nattress]

They're been in there for a long time..... They should be there in the version you have.

Those are the values that the QT generation assumes (at the moment) so to get the DPX to look the same, those values should also be used.

Graeme

 

[Noah Kadner]

Ah ok- I was a bit confused by that as well but figured it out. Graeme is referring to the Camera RGB color space that you select from the menu. Then use the Rec 709 Matrix that's a drop down in the main interface. I did that and now my QT Proxy exports look identical to what I see in Red Alert.

-Noah