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Down&OutDesigns
2009 June 5th, 07:10
my original clip size of a small clip was 95mb

i exported it with the apple pro res 422(HQ) codec with minor color correction..

the size jumped to 204.5MB

is that normal??

Janke
2009 June 5th, 11:00
Absolutely normal. 4:2:2 is an uncompressed codec, which makes HUGE files...

iThinkergoiMac
2009 June 5th, 11:09
It's not uncompressed, just close to it. But, like Janke said, it's definitely normal.

Down&OutDesigns
2009 June 5th, 20:01
ok just wondering..

what makes it such a larger file.. if its being basically compressed but not much..??

Dana Love
2009 June 6th, 06:29
It's much less compressed than HDV. The Canon records in HDV 1080i, which is a constant 25 Mbit/second data recording rate with a 4:2:0 chroma sampling format. Apple ProRes422 (http://en.wikipedia.org/wiki/Prores422)(HQ) is an intermediate codec with a variable data rate, nominally 220Mbit/second, with a 4:2:2 chroma sampling format.

HDV is not generally seen as a production-grade format, though Discovery (the defacto US standard for HD broadcast) and BBC (the defacto UK standard for HD broadcast) will accept varying amounts of HDV footage. A production-grade format would be something like DVCPRO50 or HDCAM.

ProRes422 is generally not a distribution codec, though some houses will accept it. Ironically, it's also becoming an "in camera" format with JVC, and an "on camera" transcoded format with AJA's products.

Obviously, ProRes is not a happy format with tape. When you consider MiniDV tapes give you 62 minutes of HDV footage (25Mbit/s) but only about 30 minutes for DVCPRO50 (50Mbit/s) or 15 minutes for DVCPROHD (100Mbit/s), you can imagine that ProResHQ would allow maybe 6 minutes of recording per MiniDV tape.