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Overview
Overview
ProRes Recording
The ALEXA/ALEXA XT is the first camera offer-
ing internal, ready-to-edit, QuickTime/ProRes HD.
With SUP 7.0, all cameras received a free upgrade
enabling QuickTime/ProRes 2K recording. Record-
ing in ProRes 2K is a cost-efficient alternative to
shooting ARRIRAW, as it requires less storage space
and no processing, but at the same time delivers an
image quality that is superior to that of up-scaled HD
material. With the option to capture ProRes 2K in the
4:3 aspect ratio1, the format offers true anamorphic
capture with regular 2:1 anamorphic lenses and
offers extra room for repositioning when using stan-
dard spherical lenses. New for SUP 9.0 is the ability
to shoot ProRes 4444 in Highspeed Mode.
ProRes 2K Image Aperture
When the ProRes recording resolution is switched
from HD to 2K, the captured aperture changes from
2880 pixels / 23.76 mm / 0.935" width to 2868
pixels / 23.66 mm / 0.932" width. This allows the use
of an optimized in-camera downscaler and provides
the best possible 2K image output. When capturing
ARRIRAW, it is common to use the full 2880 image
width for processing a 2K deliverable. The ARRIRAW
SDK, however, allows to process 2K images from
both 2880 and 2868 pixels width to deliver an exact
match to ProRes 2K footage when ARRIRAW was
recorded in parallel with ProRes 2K
2
.
1
4:3 ProRes 2K is available on ALEXA Plus 4:3,
ALEXA Studio, ALEXA M, ALEXA XT, ALEXA XT
Plus, ALEXA XT Studio and ALEXA XT M.
2
This only applies to ALEXA cameras with the SxS
Module. ARRIRAW T-Link output is not available in
conjunction with the XR Module or on ALEXA XT
cameras.
For more information on using ProRes 2K in different
applications, please take a look at the “ProRes 2K in
Editorial“ white paper, available at www.arri.com/
alexa/downloads.
Format
Sensor
Mode
Resolution Color Coding
Data Rate @
24 fps [Mbit/s]
1
Data Volume @
24 fps [GB/h]
1
fps Range
3 4
ProRes 422 (Proxy)
4:3 2048 x 1536 10 bit YCbCr 60 27 0.75 – 48
16:9 2048 x 1152 10 bit YCbCr 45 20 0.75 – 60
16:9 1920 x 1080 10 bit YCbCr 40 18 0.75 – 120
ProRes 422 (LT)
4:3 2048 x 1536 10 bit YCbCr 130 63 0.75 – 48
16:9 2048 x 1152 10 bit YCbCr 100 45 0.75 – 60
16:9 1920 x 1080 10 bit YCbCr 90 40 0.75 – 120
ProRes 422
4:3 2048 x 1536 10 bit YCbCr 190 87 0.75 – 48
16:9 2048 x 1152 10 bit YCbCr 140 65 0.75 – 60
16:9 1920 x 1080 10 bit YCbCr 125 57 0.75 – 120
ProRes 422 (HQ)
4:3 2048 x 1536 10 bit YCbCr 280 130 0.75 – 48
16:9 2048 x 1152 10 bit YCbCr 210 98 0.75 – 60
16:9 1920 x 1080 10 bit YCbCr 185 85 0.75 – 120
ProRes 4444
2
4:3 2048 x 1536 12 bit RGB 425 195 0.75 – 48
16:9 2048 x 1152 12 bit RGB 320 146 0.75 – 60
16:9 1920 x 1080 12 bit RGB 280 128 0.75 – 120
1
ProRes is a variable bit rate codec. The actual data rate varies with the image content.
2
ProRes 4444 provides an alpha channel, which is not used by the ALEXA.
3
All speeds adjustable with 1/1000 fps precision.
4
2K ProRes recording is limited to 30fps on 32GB SxS Pro cards