View Full Version : 4K REDCODE original downsampled Vs 1080p original but never compressed?
04-25-2007, 07:37 PM
For music-video productions (and lots of keying), of 1080p resolution, which is better:
1) 4K REDCODE --> to 1080p uncompressed
2) 1080p uncompressed RED ONE Shooting with HD-SDI output --> captured and worked uncompressed
4K REDCODE (original), downsampled Vs 1080p (original) but never compressed?
3) 1080p uncompressed RED ONE Shooting with HD-SDI output --> captured uncompressed and worked compressed with a low-compression codec more compatible (for example Apple ProRes 422 HQ 1080p)?
04-25-2007, 07:47 PM
The 4k redcode stills posted a while back looked great for keying. If 1080p uncompressed is better than that's gravy, although I doubt it will be better. Tricks like difference keying operate on luma, so you have a vague advantage with 4k redcode. And you can likely do a better de-bayed in Redcine than straight off the camera... and Redcode artifacts are extremely minimal (didn't impact keying)... I would say stick with Redcode.
But then again, if 1080p uncompressed is better, then you're better off.
04-25-2007, 10:20 PM
Even using a pessimistic estimate of the resolution consequences of using a bayer sensor, Red is probably still at least a 3K camera. And wavelet compression tends to leave high-contrast edges (like the ones between your subject and the green screen) nice and sharp. So, my bet is on 4K REDCODE RAW. Do your keying before you downsample.
04-25-2007, 10:53 PM
The only answer is to TEST it when you get the camera in your paw. Anecdotaly I've found that downconverting has given favorable results for some clients.
Personally I would take any tricky shots back to full res for keying, or if you've got the cpu power do all the keys at 4K. Keying and comping at that res will be a little errrrrr..... taxing on your resources.
Go Test Test Test....
I should add that Prores from apple is currently an unknown quantity, Dnx is also a great looking codec but I've seen it break down. Time will tell
04-26-2007, 02:37 AM
Thank you all.