Edit
Do I look like I know what a JPEG is?
If you have to zoom in and up the brightness on your monitor to 110 to see the slightest color banding, don’t use this tag. Use it for artifacts that are obvious when viewed at 1:1 resolution.
Keep in mind this is possible on PNGs and other lossless formats, particularly when using an upscaled photo or previously compressed asset; see post #35 for an example.
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