#973 Inconsistent contrast and brightness adjustment

[Tobias Knauss]

My scanner is a Canon TS5350 printer scanner combo. I noticed that all scanned greyscale images look quite pale, and I have to adjust contrast and brightness to get a good result. During some tests I found that setting contrast and brightness during scan creates a different result as setting the same values during adjustment after the scan. In my opinion this is a bug. The results should be the same if identical parameters are used, no matter at which point.
Images of various scans are attached.

[Ben Olden-Cooligan]

By default, setting brightness/contrast in your profile has your scanner itself do the brightness/contrast adjustment, while if you do it after the scan NAPS2 will do it. Hence the difference.

You can make it done by NAPS2 in both cases by checking "Apply brightness/contrast after scan" in your Advanced profile settings. This can definitely be confusing, and I might change the default behavior at some point.

[Sourceforger]

setting brightness/contrast in your profile has your scanner itself do the brightness/contrast adjustment

This sounds completely inconsistent to me. Either the profile does brightness/contrast adjustment OR the scanner itself does it.

As long as the "Apply brightness/contrast after scan" is not checked, the brightness/contrast settings in the profile should be greyed out.

And for visualizing the correlation between these two switches, they should be placed next to each other.

To make it perfect, instead of "Apply brightness/contrast after scan" it should be called "Use these brightness/contrast settings instead of scanner default settings".

[Tobias Knauss]

This is indeed confusing.

I suggest you add another pair of brightness/contrast parameters, so that one set applies to corrections done by the scanner and the other set applies to the corrections done by your software. Both parameter pairs should be placed inside a groupbox with suitable label. If that is too much for the main page, then you should move all these parameters to the advanced page.