ARRI ALEXA - Page 104

104 Operation of The Camera
Codec
The Apple ProRes codec family consists of 5 different codecs:
Name Color
coding
Data rate
@ 30 fps
Recording time on
32 GB SxS PRO @
30 fps***
max.
frame
rate**
ProRes
422 (Proxy)
YCbCr 45 Mb/s 1 h 23 min 60 fps
ProRes
422 (LT)
YCbCr 102 Mb/s 37 min 60 fps
ProRes
422
YCbCr 147 Mb/s 25 min 60 fps
ProRes
422 (HQ)
YCbCr 220 Mb/s 17 min 60 fps
ProRes
4444*
RGB* 330 Mb/s* 11 min 40 fps
*Without alpha channel (444 only)
**The maximum frame rate is also limited my the write speed of the SxS
PRO card in use, which might reduce the maximum frame rate below the
values given in the table.
***Apple ProResTM is a VBR (variable bit rate) codec. This means that the
actually available recording time depends on the image content. The number
given in the table is the MINUMUM available recording time for a 32 GB SxS
PRO card. When image content is easily compressable without loss of
image quality, the available recording time can exceed the number given in
the table.
Also note that the available recording time is given for a 32 GB SxS PRO
card at 30 fps. A lower sensor fps will increase the available recording time,
while a higher sensor fps will decrease it.
Selecting the codec that fits best for the shoot is a crucial task. Choosing a
codec with a high data rate, such as ProRes 4444, delivers the highest
image quality, but at the same time lowers the available recording time on an
SxS card.
ProRes
422 (Proxy)
On-set monitoring and proxy editing while the master
is captured with an external device.
ProRes
422 (LT)
Same as above when higher image quality is desired.
ProRes
422
Basic television application, if images do not require
adjustments in post production.
ProRes
422 (HQ)
High quality TV applications requiring color
correction.
ProRes
4444
Cinema applications requiring color correction and
pulling mattes.