Ralph and Others, On Wednesday, 2021-06-30 12:07:49 +0200, I myself wrote:
> Ralph, > > On Wednesday, 2021-05-19 18:21:57 -0700, you wrote: > > > ... > > On 2021-05-19 8:46 a.m., Dr Rainer Woitok wrote: > > > ... > > > - The PNG file from the flatbed clearly showed the original paper hav- > > > ing been rather thin, since some colours from the reverse side shone > > > slightly through, and the background colour having been faintly grey > > > rather than white. In other words, this PNG file was a fairly good > > > copy of the original. > > > > > > - But the PNG file from the ADF did show almost no shine through and a > > > more or less purely white background. Dark colours appeared slight- > > > ly darker and light colours slightly lighter than the original. The > > > effect was somewhat similar to using ImageMagick's "-normalize" opt- > > > ion. > > > ... > > Some of the pixma devices seems to have a completely different engine > > for generating scans from the ADF compared to the flatbed. > > For ADF, they return JPEG data to SANE instead of the normal raster data > > that we get from flatbed. > > I have no idea why that would be the case but they do use the same sensors. > > I have meanwhile opened a support case with Canon complaining about the > low quality of ADF scans. In their response Canon pointed out that ADF > (at least normally) is optimized for speed rather than quality and sugg- > ested testing with "IJ Scan Utility" using the various settings of the > "Advanced Mode" provided by "ScanGear". So I reanimated my old Windows > Vista laptop, installed "IJ Scan Utility" from the Canon CD and started > it. > > I selected "Document (ADF Simplex)", "A4", and "Color" in the input and > "300 dpi" in the output section, and under "Image Settings" I left "Im- > age Adjustment" at "Document" and set "Unsharp Mask" and "Descreen" to > "OFF" and "Reduce Dust and Scratches" and "Grain Corretcion" to "None". > Hitting "Scan" I eventually obtained file "ScanGear-ADF-Doc.png". > > In the second run I just changed "Image Adjustment" to "None" (the only > alternative offered) and scanned to file "ScanGear-ADF-None.png". > > Finally, I changed the Source to "Platen" which forced "Paper Size" to > "Full Platen" and "Image Adjustment" to "None" (greying both out), and > received file "ScanGear-Flatbed.png". > > Here are the file sizes: > > $ ls -l ScanGear-* > -rwx------ 1 rainer rainer 3324661 2021-06-29 15:48 ScanGear-ADF-Doc.png > -rwx------ 1 rainer rainer 11142577 2021-06-29 15:49 ScanGear-ADF-None.png > -rwx------ 1 rainer rainer 15357308 2021-06-29 15:49 ScanGear-Flatbed.png > $ > > Files "ScanGear-ADF-Doc.png" and "ScanGear-Flatbed.png" are similar in > size and quality to the files I originally obtained using "scanimage" on > Linux, while the quality of file "ScanGear-ADF-None.png" is comparable > to that of "ScanGear-Flatbed.png". So setting "Image Adjustment" to > "None" in the "ScanGear" GUI does produce a decent ADF scan on the MB- > 5150. Now we "just" need to get the same result from the "pixma"back- > end ... > > By the way: On their web site at > > > https://www.canon-europe.com/support/consumer_products/products/fax__multifunctionals/inkjet/maxify_mb_series/maxify_mb5150.html?type=drivers&language=en&os=linux%20(64-bit) > > Canon is offering the source code for both, an IJ Printer Driver version > 5.40 and ScanGear MP version 3.40, of which the former is even available > as Gentoo package "net-print/cnijfilter2" version 5.90. Would these be > of any help? > > Sincerely, > Rainer However, up to now I never received an answer. Did I just miss it or is there really nothing to be done to make _scanner access now easy_ for the Canon Maxify MB5150? Sincerely, Rainer
