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Steve Phillipps
04-20-2008, 02:36 PM
Am I right in thiking that Red RAW footage has "linear" gamma, and that it needs a gamma curve putting onto it in post processing? Not a real expert at this so forgive me, but on Phantom HD the camera has gamma set at 1 which I believe is a straight line and looks quite flat, and for viewing it needs a gamma curve of about 2 applying.
Can anyone with more expertise than me contribute?
Thanks,
Steve

Graeme Nattress
04-20-2008, 02:38 PM
Yes, the sensor and recording are linear light data. To see that, select gamma=1 in Redcine or Linear Light in Red Alert.

Graeme

Steve Phillipps
04-20-2008, 02:58 PM
So when it gets recorded as REDCODE it's got gamma correction included yes?
I keep forgetting that it's not recorded as RAW.
Steve

Graeme Nattress
04-20-2008, 02:59 PM
RAW get recorded and RAW data is linear light.

Graeme

Steve Phillipps
04-20-2008, 03:08 PM
Excuse my confusion, I said I wasn't an expert. So in Red Alert or Cine you'd typically select gamma=2.2 or similar?
Steve

Graeme Nattress
04-20-2008, 03:10 PM
I'd expect to normally use REC709 gamma curve, which is more suitable than a straight power function most of the time, or REDLOG.

Graeme

Steve Phillipps
04-20-2008, 03:13 PM
Thanks Graeme.