(04-21-2019, 08:49 AM)Fennec Wrote: To give you an example of what I'm seeing when I use B/C options: https://i.imgur.com/iT7cfWc.png
If you take a look at the ear where the black arrow is pointing, you can see this sort've blurry pixel mess that surrounds the edge of the ear. Granted, for the purpose of demonstration, I used ctrl+mouse wheel and zoomed in at 250% to clearly show it, but It's still somewhat noticeable at 100%, just not as much.
Strangely, I don't see this issue with option A -- it just looks blurry another way lol.
That blurry mess is JPEG compression artifacts. The tell-tale sign is the squareish pattern (JPEG compression first divides the images into 8x8 tiles):
So, your source image is crappy. With options B/C you keep the crap as it is. With option A, you blend the crap with the rest (because rescaling is computing new pixels values by cleverly averaging pixels in the image at the original size), so it goes under the radar (but participates in the general impression of blurriness).
As usual, Garbage In, Garbage out.