redspace difference

[martin bendersky]

Hi, my name is Martin Bendersky. I'm working as a DIT in a big tv show with two cameras (build 20.1.3). I notice that with the same configuration in the two cameras the color is deferent. It's possible that the red-space in each camera has a difference? I tried tree deferents cameras with the same exposure, same lens, same F stop and same light with a human face, 18% grey and a chroma check card and i still see the difference.
If you have any suggestion or comment i would love to hear it.

[Tim Sutherland]

What are you seeing the difference on? The camera monitor? HDSDI Monitor? In the computer?

Besides possible differences in the monitors, try going to Video -> Look -> Clear on each camera and see if you still see the difference.

[David Mullen ASC]

I've seen the same issues between multiple RED cameras, some slight color cast variations. I suspect they exist in all digital cameras, it's just that a Sony or whatnot applies a certain amount of signal processing to allow matching between cameras, whereas the RED is designed to be a RAW camera, so no signal processing other than for simple on-set monitoring purposes -- you're basically recording what the sensor is responding to.

Related to this, I've noticed with digital in general, you can now see a lot of color variations between lenses in real time.

[Rainer Fritz]

Have you done a blackshading on all 3 cams ? Are any looks applied? Best is when checking out at the rental to flash the cams new, so they are fresh, doing a blackshading and setting them up as u like... after that i saw also differnces between cameras, but in a value which is absolutely in a range that is ok....

[martin bendersky]

I've seen the same issues between multiple RED cameras, some slight color cast variations. I suspect they exist in all digital cameras, it's just that a Sony or whatnot applies a certain amount of signal processing to allow matching between cameras, whereas the RED is designed to be a RAW camera, so no signal processing other than for simple on-set monitoring purposes -- you're basically recording what the sensor is responding to.

Related to this, I've noticed with digital in general, you can now see a lot of color variations between lenses in real time.

Yes... the big problem is that all the material is compress first to a pro res 4:2:2 and then to a 14:1. We send all the footage to italy (we are shooting in Argentina) attach to the camera lut (in this case the redspace) and they make an offline with this footage. It's annoying to see the offline with a variation in color between cameras (is a big variation).
I went to the post house in Argentina and i saw the material in the scratch. And there it was, again, the color variation, in raw and in redspace. One camera was a nice tungsten and the other one was a scary magenta.
Finally at the end of the week i changed the camera. Now everything is ok. With the bad camera i restored all the camera values and i did a black shading. I couldn't compare it again yet. Tks for listening...

[martin bendersky]

Have you done a blackshading on all 3 cams ? Are any looks applied? Best is when checking out at the rental to flash the cams new, so they are fresh, doing a blackshading and setting them up as u like... after that i saw also differnces between cameras, but in a value which is absolutely in a range that is ok....

Yes i did it. But one is a nice tungesten and the other one is a scary magenta.

[martin bendersky]

What are you seeing the difference on? The camera monitor? HDSDI Monitor? In the computer?

Besides possible differences in the monitors, try going to Video -> Look -> Clear on each camera and see if you still see the difference.


I saw the image in monitor panasonic BT LH 1760 hdsdi, a mac book pro 13'' with the red alert and in the post house with the scratch

[Raphael Varandas]

I had a problem like this in a project with 2 cams, but it was a preview issue.
There was everything right in the RAW.
Otherwise shooting in b.21 no problem at all with 2 or 3 cams.

My 2 coins in 21.3.2...

Cheers

D.I.T on Machado de Assis " Uns Braços" - work in progress - RED One Build 21.3.2 4K 2:1 Especial Episode for RECORD TV- Brasil

[J. Eric Camp]

No what Martin is talking about is not a simple sensor variation. "scary magenta" sounds like an issue with a specific camera.

[Raphael Varandas]

No what Martin is talking about is not a simple sensor variation. "scary magenta" sounds like an issue with a specific camera.

Reasonable...agreed