Working on 10-12bit 1:1 on 5D2 , as we know 3x crop works with 10 & 12 bit reduction but not 1:1 really well .
Thou in 12bit 1:1 you can record with corruption on every other frame on the top 100 or so lines .
I'm currently seeing the feasible of using bit reduction in a up coming documentary I been hired to shoot in 2 weeks for the sierra club (usa)
My needs are long shoot times , so low bite rate fits the bill .
Here a list of resolution's size I was possibly thinking of using with 12bit in 1:1 (as there corruption on the top of frame)
with the adjusted crop to remove corruption. I also listed the file size for 60 second or so to get max time for minimum card space
The base line is 14 bit 1856x928 23.976 fps (My minimum spec. for HD broadcast as it need to be up upscaled)
1856x928 23.976 14bit 59.9 seconds 1437 frames 4.05 GB 1:1 Liveview ( 2:1 A.R.)
1856x1114 23.976 12bit 64.8 seconds 1554 frames 4.51 GB (crop adjust 1856x988) 126 line crop 1.878542510121457 A.R.
1856x1044 23.976 12bit 64.8 seconds 1554 frames 4.23 GB (Crop Adjust 1856x953) 91 line crop 1.947534102833158 A.R.
1856x1004 23.976 12bit 60.3 seconds 1447 frames 3.78 GB (crop Adjust 1856x932) 72 lines crop 1.991416309012876 A.R.
1856x928 23.976 12bit 60.1 seconds 1442 frames 3.49 GB (crop adjust 1856x895) 33 lines crop 2.073743016759777 A.R.
So There is really no saving after cropping , but 3x crop mode is a different matter all together .
Here 10bit really save me , as I can have to 20min per 64GB Card @ 1920x1076 @ 23.976fps
Thou the field of view is reduced , looks like the 24mm will gets a work out

1920x1076 23.976 10bit 59.9 seconds 1437 frames 3.47 GB (3x Crop Mode) 1.784386617100372 A.R.
So I save about 500 MB per minute which will add up fast. 4x 64gb card should be around 80 min's of 10bit 2K or 1920x1076.
Now I can use my slower 60MB/s CF cards to get
1856x928 23.976 10bit 60.1 seconds 1443 frames 2.91 GB (3x crop) (2:1 A.R.)
It looks like I'll being shooting in 10bit 3x crop for this doc.
Now for the real reason I started this post , as I said I'm work on 1:1 liveview 5d2 10-12bit.
I've being working on older code with .raw , just to keep it as simple as possible before I move on to .mlv full & mlv_lite.
At this Point I can record 10bit & 12bit , with out any lockups or screen freezes all overlays are working while recording bit reduction.
When not in bit reduction it return to 14bit and of course it work without problems.
Now the Problem

there is always a problem , my issue is decoding the .raw to dngs
My question is can I convert the .raw to .mlv ? as mlv_dump seem not to understand .raw
I'm currently uploading some of the .raw file to my Google drive to share , when done I'll post the links.