Hypothesis - Color maps can only be converted to a png of appropriate file size if the map is always in a file format - NEVER scanned.
I have been wrestling with some color maps that were sent to me as pdf files. The pdf files were created from scans of hand-drawn maps. I could not convert the pdf files to png files of acceptable size. So, I scanned them.
The scanned files are always too large, no matter what sequence I use to get to png files.
Has anyone found a way to scan a color map, and create a png file of small-enough size? I think we may have to say that only digitally-created maps can be in color. I imagine it is the "white" background that adds too much image information into the file, making the png file too large.
Thoughts?