Sony a9III File Bit Size

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DavidT

DavidT

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Hello,
I am curious as I just read the Sony a9III owners manual and like the a1 we have the option of RAW, Lossless RAW L,M,S and then Compressed RAW. In the a1 we go to a 12 bit file when going to compressed.

The a9III manual simply states "RAW images recored with this camera have a resolution of 14 bits per pixel." It continues to say "Compressed records images in compressed RAW format. The file size of the image will be approximately half of that with [Uncompressed]."

So this leads me to believe that no matter the RAW setting the camera maintains 14 bit.

Anyone know for sure if this is true or not?
 
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An example extracted from one of my A9III compressed pictures (Using RAW Digger tool) :

Screenshot 2024-02-24 at 13.00.13.png


Screenshot 2024-02-24 at 13.00.24.png
 
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The Sony rep who covers TX follows me on IG and we chat now and then. I asked him and he didn’t know about it but is going to look into it. I’ll let you all know what Tony says.
 
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SONY A9III help guide.

Chapter : "Image Quality Settings: File Format (still image)" :

Screenshot 2024-02-24 at 21.12.16.png


It is clear, there is no distinction according to the type of file (compressed or not, more or less compressed). All A9III RAW files are 14 bits ;)
 
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Regarding fps, A9III tests conducted this morning:

Screenshot 2024-02-25 at 11.26.26.png


Conclusion:
- If you need 120 fps, use Compressed
- For the rest, the fps are exactly the same, regardless of the compression ratio used
 
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PhD69 said:
@DavidT Is that what you were expecting as information? (The datasheet in post #7)
Click to expand...
Yeah pretty much. I figured compressed like on the a1 would give you more files before hitting the buffer and would clear faster.

What shocked me is no mention of bit file drop so if it stays at 14 bit you’re still getting all the info and dynamic range as in lossless. That’s a big win!
 
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@DavidT I've taken a set of pictures with the A9III and the A1, @ all compression modes (with RAW format and with RAW & HEIF format as well).

Using RawDigger, I get information related to :
- Compression (RAWDigger)
- Sony Raw File Type (RAWDigger)
- Compressed Bits Per Pixel (RAWDigger)
- RAW File Type (RAWDigger)
- Bits Per Sample

As mentioned before, results are not 100% clear.

Thus, I just got in touch with RAWDigger support.
They answered very rapidly and gave me a first bunch of information, adding : "In addition to the above: our Sony A9III sample set is not complete. Could you please shot a complete set for us:
a) All RAW compression modes, Full-frame (according to manual, A9III
implements four RAW formats: Uncompressed and three compressed modes
L/M/S).
b) All RAW compression modes, APS-C crop."

I've sent my Excel sheet with my findings and have shared my RAW files using a Dropbox folder.

They've just opened the Excel sheet.

We should have interesting feedback rapidly, which I'll share with you of course ;)
 
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PhD69 said:
@DavidT I've taken a set of pictures with the A9III and the A1, @ all compression modes (with RAW format and with RAW & HEIF format as well).

Using RawDigger, I get information related to :
- Compression (RAWDigger)
- Sony Raw File Type (RAWDigger)
- Compressed Bits Per Pixel (RAWDigger)
- RAW File Type (RAWDigger)
- Bits Per Sample

As mentioned before, results are not 100% clear.

Thus, I just got in touch with RAWDigger support.
They answered very rapidly and gave me a first bunch of information, adding : "In addition to the above: our Sony A9III sample set is not complete. Could you please shot a complete set for us:
a) All RAW compression modes, Full-frame (according to manual, A9III
implements four RAW formats: Uncompressed and three compressed modes
L/M/S).
b) All RAW compression modes, APS-C crop."

I've sent my Excel sheet with my findings and have shared my RAW files using a Dropbox folder.

They've just opened the Excel sheet.

We should have interesting feedback rapidly, which I'll share with you of course ;)
Click to expand...
That’s awesome!!!!!
 
That is interesting info. I know my r5 drops the bit depth from 14 to 12 if you shoot at the max 20 frames per second and drop to 13 if you use the pretty fast setting. It's not related to the file compression.

Once one is greater than iso 400 or so there is no impact on image quality from using 12 bit.
 
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My previous information supplemented by the comments of the LibRaw team (editor of RAWDigger software).
See the dark blue areas, published with their kind permission.

Camera body : A9III
File format : RAW - Full Frame

Screenshot 2024-02-28 at 17.14.33.png
 
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