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Tim Shawcross
17-Jan-2007, 05:34
I've been having some trouble with my copy of Silverfast AI for my canon scanner. My problem is the preview in silverfast does not match the file opened in photoshop. Often I've noticed the colours are different, making colour correction in the scanning software is useless, as the when the scan is opened in photoshop the colours are different. Also, the dynamic range of the scanned file seems to be radically different from the preview.

To examplify I've attached two screen captures. The first is the preview in silverfast and the second is the scan opened in photoshop - you can see that large areas are blown out to white and lots of detail isn't in the scan which is present in the preview.

I'm using Adobe RGB colour space, and in silverfast i have internal set to ICM.

This is especially frustrating as the manual states in the colour management chapter that silverfast features 'automatic matching with photoshop'.

Thoughts?

Tim

Kirk Gittings
17-Jan-2007, 10:07
Which version of SF are you using?

Tim Shawcross
17-Jan-2007, 16:35
Hey Kirk - it's version 6.4.4r2. I'm using Photoshop CS1

Tim

Tim Lookingbill
18-Jan-2007, 13:08
See what you get assigning your monitor profile and/or sRGB.

I'm getting the same thing with my Epson 4870 scanning negatives in 48>24bit mode with SF-SE vs 6.4.4r2 and 6.4.4r6. I'm on a Mac OS 9.2.2 Pismo Powerbook. If I assign my external CRT monitor profile, which is close to sRGB, the previews match to the SF prescan preview exactly, well sort of. The red readouts in SF of intense lipstick colored flowers will be 230 but in PS will be 235 and previews show this as well. It's subtle though. Apple DigitalColormeter applet which reads off the adjusted vLUT confirms this as well.

I get no responses to this at the Silverfast forum site.

Tim Lookingbill
18-Jan-2007, 13:17
Another thing. In my searches on the web on this I came across this 2005 Luminous Landscape forum thread. The answer from Silverfast is near the bottom.

http://luminous-landscape.com/forum/lofiversion/index.php/t9158.html

It's not exactly like our issues because it deals with the working space differences between AdobeRGB and ProPhotoRGB and whether an assigning or writing data to these spaces is taking place within the scanner.

It's an interesting insight on how color management may not work perfect integrating with the internal mechanisms of scanners.

Tim Shawcross
25-Jan-2007, 16:53
I eventually got an answer from Silverfast support - they instructed me to deleted the preferences folder in the Application Data folder, and then restart the program - this did the trick and now previews are matching the scans.


tim

Kirk Gittings
25-Jan-2007, 17:32
I really apologize for not checking this thread. I have been very busy. Deleting the preferences file is really (after rebooting once) the first line of recourse with any problems with SF. It is the only way to truly reset all the defaults.

Tim Lookingbill
26-Jan-2007, 12:53
Thanks, Kirk.

I take it trashing the preferences dumps all established edits from the previous scan session.

Any installing tips going from SF-SE 6.4.4r2 to 6.4.4r6. I believe I'm on my second upgrade version from the original bundled SF-SE that came with my Epson 4870. Should I trash the entire SF folder and install the 6.4.4r6 from scratch?

Kirk Gittings
26-Jan-2007, 15:14
Only if you think there are issues with it. For some reason that file collects some trash instructions that can throw things off. At the first sign of issues I dump it. If I have saved some valuable profiles I copy them out and paste them back in the new folder.

Tim Shawcross
26-Jan-2007, 17:20
Thanks for the replys - I'll remember in the future now if I'm having any issues to delete the Pref folders and restart as a first point of call. At the moment though everything is back up and running smoothly!

tim

Tim Shawcross
29-Jan-2007, 16:19
Just another update - I'm still having problems. At the moment, the problem I described above happens each time I do a new prescan and then scan. So at the moment, I have to delete the PREF folder, load silverfast, scan an image, then close, delete PREF again and reload silverfast for every new prescan/scan (so for 4x5 every image). The problem doesn't appear to be happen with BW negs, only colour transparencies (though if I scan colour transparencies in BW mode the problem is there).

Tim

Kirk Gittings
29-Jan-2007, 17:21
Something is corrupted. Have you checked for recent updates? Have you reinstalled? Both Sf and the Epson software?

Tim Shawcross
29-Jan-2007, 18:24
Kirk- I downloaded and installed the latest update after I started having the problem (before I new about deleting the PREF folder.) I'll try uninstalling it again and also unistalling the canon software and scanner and see if that fixes the problem

tim

Tim Lookingbill
30-Jan-2007, 18:51
Geez, you ain't kiddin' this is a buggy program. I trashed the pref folder and nothing seemed to change. Upgraded to 6.4.4r6 and now the preview pane expands outside the bounds of my display desktop with the corner grab enlarger out of reach.

So I decided to just use SF-SE to scan negatives as positives in HDR mode and went to switch the CMS select from AdobeRGB to NONE and I now get a dialog box warning me... "can't find monitor>internal:

internal can't be found".

Kept CMS on to get rid of the dialog box and started investigating a bit with SF's CMS implementation to find out what space it actually is writing my neg/pos scans to. Noticed the SF RGB output readouts didn't match up to PS's with slightly more saturated previews in PS with the embedded canned scanner profile. I found I could get the same readouts converting to AdobeRGB.

But I wanted to know what the current numbers represented so I set Soft Proof to sRGB/Relative Intent, RGB info palette to Proof Colors and assigned sRGB to the scans. The numbers are in sRGB.

So SF is delivering the actual data in sRGB, giving internal SF readouts in AdobeRGB and assigning a canned scanner profile to generate previews that match close enough but not perfect.

Aside from this I still get HDR scans that have a lower Standard Deviation number in PS's Histogram dialog than Epson's RAW version. Not sure if this is a good thing or bad because I'm assuming a lower SD means less noise ratio per pixel data captured. Please correct me if I'm wrong.

Kirk Gittings
30-Jan-2007, 19:24
Actually after using Sf for 4 or 5 years I don't find it particularly buggy compared to other windows based programs. I rarely have problems with SF. I have had far more problems with scanners than software.