Is there a way to adjust contrast for Simple Scan?

Simple Scan is - by its name - simple.

There is this outstanding bug-report with a proposed pull-request.

However the main dev said:

I'm a little worried about how consistent drivers are with these settings, but I support the patch if it works. This setting will be "advanced" as most users will adjust the brightness/contrast after the scan is completed.

An alternative to Simple Scan is xsane from the software-center.

At first glance, it appears to be much more complex - however, its worth spending a small amount of time - it has great control over all aspects of scanning including contrast settings as shown.

Simple Scan 3.8 has available in Saucy Salamander, introducing various refinements and long-awaited features.

Navigating now to Simple Scan-->Document-->Preferences, summons the Preferences dialog containing the newly-implemented Brightness and Contrast additions.

Moreover, adjusting values for Brightness and Contrast is to be hassle-free performed via a draggable pointer, useful to increase and decrease the values per-user's likeness.

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