Sony a7 III Mode D'emploi page 43

Selecting a still image size/image quality
JPEG Image Size
The larger the image size, the more detail will be reproduced when the
image is printed on large-format paper. The smaller the image size, the
more images can be recorded.
MENU  (Camera Settings 1)  [
desired setting.
When [ Aspect Ratio] is set to 3:2
L: 24M 6000×4000 pixels
M: 10M 3936×2624 pixels
S: 6.0M
3008×2000 pixels
When recording in the APS-C-equivalent size
When [ Aspect Ratio] is set to 3:2
L: 10M 3936×2624 pixels
M: 6.0M 3008×2000 pixels
S: 2.6M 1968×1312 pixels
Note
• When [ File Format] is set to [RAW] or [RAW & JPEG], the image size for
RAW images corresponds to "L."
JPEG Image Size] 
When [ Aspect Ratio] is set to 16:9
L: 20M 6000×3376 pixels
M: 8.7M 3936×2216 pixels
S: 5.1M
3008×1688 pixels
When [ Aspect Ratio] is set to 16:9
L: 8.7M 3936×2216 pixels
M: 5.1M 3008×1688 pixels
S: 2.2M 1968×1112 pixels
GB
GB
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