Mike Chaney's Tech Corner

I cannot get decent results after profiling through PP and would appreciate any suggestions. I have a high quality colour print from a supplier of professional inks and paper and its digital source file. In PS7 the print compares well with the digital file. However, a scan of the print to PS7 is nowhere close. Sampling white from the scan for example yields 235/235/236 (R G B ) whereas sampling the digital file yields 255/255/255. Beside white, colours are way off too. These results apply with and without assigning a profile ( PP or Canon supply )
The only way I can get decent scan quality is to sample white in the scanning software and to apply some curves adjustments in PS7 after assigning the Canon profile, all rather defeating the purpose of profiling the scanner. Has anybody got any suggestions pleeeese?

Hi,
What scanning software are you using? The Canon software is really not good enough for profile making and Mike recommends Vuescan.
I'm not even sure if the Canon scanning software allows for working with a profile, as does Vuescan.
I have a Canon 8400F and successfully made a profile with PP. Vuescan can also make a profile with an IT8 target (as supplied with PP) but does not take account of the calibration data for the target as PP does.
Terry

Hi Terry-M,
Thanks for your response. I am using the Canon software and assign the profile in PS7. Have tried both the Canon and PP derived profiles. I also have an Epson PX730WD all-in-one from which I get similar results to the Canon.
Following your message I have downloaded the trial version of ViewScan which doesn't appear to have any more features than the Canon software. A scan from ViewScan gives a very similar appearance to scans from Canon and Epson software. However, I cannot produce a profile with the trial version so cannot conclude anything from that other than all the basic scans look 'similar' with whites all looking more grey so I don't feel inclined to splash the cash just yet.
The message in PP in the Canon profile from the IT8 target shows good exposure, WB, LV, low number of patches marked 'X' and excellent shadow detail and a good histogram with no clipping.
I had the thought that perhaps PP had become corrupted so I did an uninstall and reinstall with no change in outcome.
This is a complete mystery to me especially as I have profiled many many printer, paper and ink combinations with very good results.
Perhaps my methodology is at fault. I shall reread the PP help pages yet again. Meanwhile I look forward to any more comments that you and others might have.

Viewscan has the ability to save a "raw" file. This is a 48 bit tiff that has not been adjusted in anyway by the scanning software and therefore not "distorted" in any way wrt to colour etc. Profile Prism is able to accept this file (it may look dark to the eye) and give good results.
Read the PP info on the web site, also in PP Help.
Terry

PS. It's only the Pro version of Vuescan that can make raw files and utilise profiles.

Hi,

My early version of profile prism lets you to edit the pp produced profile (but not others). Maybe worth a try.

Best wishes,
Ray

Only printer profiles can be edited.
Terry

Thanks for the suggestion Ray but Terry is quite right. My version of PP only permits editing of printer profiles.

Hi,
      I finally obtained 'reasonable' scanning results.
Firstly for anyone who has followed this item, don't make the same mistake as I did. Because I had a high quality print and its digital origin file, I was comparing my scan results the the origin file, both in PS7. Don't do that. Instead, under good daylight conditions compare the scanned image with the scan on screen. Here is what I did using the Canon software:
       With the IT8 target and the high quality print sample (because it has a greyscale) in place on the platten, open CanoScan Toolbox. Enter a filename and set a destination to save the scan to ( eg Desktop ).Set a programme to view the scan in. Scan - opens ScanGear CS with an image preview. Reset any image adjustments. Execute a scanner calibration.
      Sample white and neutral grey patches and adjust the black slider on the histogram. This gave readings on the histogram of 28,142,255. Re sample the neutral grey and white patches. This gave histogram readings readings of 28,128,255. Save the setting for use with future photo scans. Select the IT8 target.
      Scan. Open the scanned file in PP and set the corner markers. This gave a message 243 = exposure, 0% white balance , 4% lighting variance, 2 patches marked as 'X' and excellent shadow detail.
       Create Profile.
       Smile and enjoy.