Why not JPEG?

[FrankMi]

Someone asked me if I could show the before and after post processing for dealing with JPEG Compression Artifacts. In-camera JPEG conversion will often create several issues that you don't normally see when using RAW images. The most common is Compression Artifacts of Luma and Color Noise but also Mosquito Noise and Checkerboarding. The in-camera JPEG sharpening can also cause significant white and black halos around high contrast edges in an image when you look at the image detail.

I am not referring as much to the https://www.cambridgeincolour.com/tu...mage-noise.htm as I am to the additional noise created by the in-camera JPEG conversion process.

Often you won't see the noise at normal (less than 200%) viewing sizes but if if the noise is removed, the image is more pleasing to look at.

This SOOC image had very little mosquito noise and almost no checkerboarding but you can see the compression (luma and color noise) artifacts:



And here is the same image after removal of the compression artifacts:



I have a lot of older JPEG images that I can't reshoot with my DSLR in RAW mode so I am hoping to get better at dealing with the in-camera JPEG compression issues for these older irreplaceable images.

[TonyCooper]

Aside from your compression issues, what is the device in the
photograph? Looks like an old sewing machine, but I've never
seen a belt-drive sewing machine.

[FrankMi]

Aside from your compression issues, what is the device in the
photograph? Looks like an old sewing machine, but I've never
seen a belt-drive sewing machine.

Sorry Tony, more detail at Ye Olde Graphophone.