There is a pretty easy image which I want to behave monochrome:
You can see on the left, and also on top there is one thin line which seems semi-transparent.
I dropped the colors by selecting Image > Mode > Grayscale, then selecting Image > Mode > Duotone (with only black as tint).
(I'm not sure this is the right way to my goal)
So, there are those semi-transparent sides, but okay, I don't care, because if I drop a background behind it they are gone:
However, how can I limit the colors to be really duo? I.e. only full black, and full white (and maybe 100% transparent as third)?
Back to my image: I want to reduce the size: Image > Image size (with Automatic resample):
Now even with the background:
And also without the background:
I got a massive undeniable semi-transparency at the sides. Now it's not hidden by adding a solid background underneath.
So: my goal is to have an image with only Black and White (no intermittent shades), with optionally a 100% transparency. This way I will be able to resize the image without those annoying transparency effects on the sides (I guess/hope).