2009/2/1 Crypto <crypto at online.de>: > 2.) In scanning software such as gscan2pdf etc. there is an option to set > contrast and brightness. Brightness goes from -100 (I suppose to make scans > darker) to +100 (makes scans brighter). I can set this option to positive > values and get brighter scans, but when I attempt to get darker scans I get > an error message "Unknown message: Argument "" isn't numeric in subtraction > (-) at /usr/bin/scanimage.pl line 357". This also happens if I use different > backends for scanning such as scanadf.pl. In scanadf.pl it's line 380 but > same error otherwise.
This is a bug in gscan2pdf. If you post the output for scanimage --help I'll try and reproduce it. Regards Jeff