Recording Live Events

Don't you think 24p (that is 6 frames less then 30p) would be minor on the file size?
How 1920x1080 JPG picture per example would be the same file size then 1280x720p?
I think like the sony codec is a Variable Bit Rate, when you change 1080p to 720p the bit rate is a constant 35mbps and compression is better then 1080p.
But in the case of 24p I think 24p is really 29.97p and the file size would be the same.

Another question... 4:2:0 is it very bad compared to 4:2:2?
THANK YOU ALL!
 
DJBROCA said:
Don't you think 24p (that is 6 frames less then 30p) would be minor on the file size?
How 1920x1080 JPG picture per example would be the same file size then 1280x720p?
I think like the sony codec is a Variable Bit Rate, when you change 1080p to 720p the bit rate is a constant 35mbps and compression is better then 1080p.
But in the case of 24p I think 24p is really 29.97p and the file size would be the same.

Another question... 4:2:0 is it very bad compared to 4:2:2?
THANK YOU ALL!
Click to expand...

24p is really 24p, unless you are using HD-SDI out to record, then its 29.97 with pull down added. (If recording to Nanoflash it can remove the pulldown on the fly.)

4.2.0 isn't noticeable unless there is extreme color grading, green screening, or some other severe use of color. It can even do those if you're careful.
 
DJBROCA said:
Don't you think 24p (that is 6 frames less then 30p) would be minor on the file size?
How 1920x1080 JPG picture per example would be the same file size then 1280x720p?
I think like the sony codec is a Variable Bit Rate, when you change 1080p to 720p the bit rate is a constant 35mbps and compression is better then 1080p.
But in the case of 24p I think 24p is really 29.97p and the file size would be the same.

Another question... 4:2:0 is it very bad compared to 4:2:2?
THANK YOU ALL!
Click to expand...


XDCam is 35mb/s, regardless of 24, 30 or 60P frame rates in REGULAR recording modes. What DOES change is the quality of the frame. At 24P, there's 25% more bandwidth available to encode EACH frame, so quality is slightly better than 30P. 720P/24 would theoretically be the best quality from a compression standpoint, but realistically, the 4:2:0 color subsampling starts to stretch a bit too thin for my liking.

4:2:2 has twice as many vertical color samples as 4:2:0, so it looks quite a bit better if the frame contains intensely-saturated colors with hard edges, like fire engines, red flags, etc., particularly if you're shooting HiSat matrix. If you're shooting a winter scene with snow and bare trees, there's not much color to show up the difference.

As stated already, 24P on to SxS is TRUE 24P. HD-SDI output is embedded in 60i stream, like HDV, with pulldown.

If your's shooting a movie and have no budget for a Wafian or even a NanoFlash, 24P and Detail Enh OFF are going to produce the cleanest MPEG2 stream.
 
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