Epson Stylus SX525WD: scanner resolution can only be 75, 300, 1200 and 2400

[Frédéric Bron]

> Educated guess:  The list is what's actually supported by the software
> and the scanner.  Putting in *any* value probably doesn't reflect what
> the scanner actually does, and probably is the software converting the
> scanned data into the resolution that you think you've picked.

My Epson scanner is natively 2400 dpi. So I can imagine easily that
the following resolutions should be available:
2400 (native),
1200 (every 2 pixels),
800 (every 3 pixels),
600 (every 4 pixels),
480 (every 5 pixels),
400 (every 6 pixels),
300 (every 8 pixels),
150 (every 16 pixels),
75 (every 32 pixels)...
But I understand that the scanner may provide only a few values amont
that list and that the Windows software may in fact interpolate to get
intermediate values without the user knowing about it.

However, how do you understand the fact that xsane and scanimage lists
are different (75, 150 300, 600, 1200, 2400 vs 75, 300, 1200, 2400)?

Frédéric