Thanks. But you really should use png-8 instead of png-24 for black&white scans. If you use some of the new PS, you need to go to File -> Export -> Save for Web (in older just File -> Save for Web) or alternatively Alt+Shift+Ctrl+S.
This still relevant to this day: https://www.insidescanlation.com/etc/how-to-edit-manga-with-photoshop/rawr/editguide/3 (how much colors is up to you, but in case of those scans I'd say 32-64 will be more than enough)
Also, uncheck "convert to s-rgb" if it's there.
The size of each scan is 2-3 times more than it should be (i.e. 1.8 MB instead of around 700 KB for example) and they have non-grayscale color....How did you even notice?
The nongrayscale color is probably because I was messing around with the brightness and contrast to get rid of the extra pixelization... welp, thanksThe size of each scan is 2-3 times more than it should be (i.e. 1.8 MB instead of around 700 KB for example) and they have non-grayscale color.