Scanner profiling/workflow question

[ehasler]

Having had problems with my old scanner, I've recently replaced it with a new Nikon, however I'm finding it quite difficult to get results that I'm totally happy with in terms of accurate colour matching with the original slides. I was hoping some of the experts on here could give me some advice!

My monitor is calibrated and profiled with a Colorvision Spyder and OptiCal, and from what I can see from various test images, it is pretty accurate.

I've installed NikonScan 4 alongside my existing copy of Vuescan as I wanted to compare the two apps, and have created a Vuescan profile using IT8 targets from Wolf Faust. As Nikonscan doesn't support scanner profiles, I've turned off it's internal colour management, and have created a separate ICC profile using a free profile maker called IPhotoMinusICC which was recommended by Wolf Faust.

Having done some testing to compare the two apps, I'm now using NikonScan, as Vuescan produced scans where lines are more jagged and pixely than Nikonscan, even with all processing turned off in both apps.

My basic workflow is as follows:

1. Preview and scan slide from Nikonscan, with all colour management/sharpening/curves etc... switched off. The only thing I have enabled is ICE and grain removal.

2. Save as TIFF file and open using Photoshop

3. Preserve profile (which is sRGB) on opening, then assign my custom scanner profile to the image and finally convert to Adobe RGB 1998 (my default Photoshop working space).

4. Run AutoLevels

After all this, some scans look very similar to the original slides, but others are not. Is this normal, and do I just need to deal with the inaccurate ones by tweaking in Photoshop, or should a properly calibrated and profiled scanner produce accurate results most of the time?

Also, my other concern is that with Nikon's own colour management switched off, it only seems to output in sRGB which I understand has a smaller gamut than Adobe RGB 1998, so I assume that I'm not extracting all that I should be able to from my slides. Certainly the original scans look very washed out before I assign my custom profile to them in Photoshop. I would have thought that the scanner should produce better results as standard.

So far, my most accurate scans have been from Nikonscan using the above method, but I'm still not 100% happy with them.

Has anyone used SilverFast? From what I've seen, this may offer better results than Nikonscan (as it supports profiles), but I'm reluctant to pay even more money for software if I can get decent results with what I've got.

I'd be very grateful for any advice or suggestions!

[te51cle]

I think your main problem there is the fact that the scanner is using sRGB. According to my book sRGB is based on HDTV colour standard for broadcast. Whilst it is great for web page design it is inappropriate for print work. It clips the CMYK gamut so that you never get more than 75-80% cyan ink in your CMYK separations. You'll inevitably be losing even more information in the conversion from sRGB to Adobe RGB.

The Adobe RGB (1998) colour space is the one to scan your images in so the first thing I'd do is find a way of setting up your scanner to do that. I have never used a Nikon scanner so have no experience with their software I'm afraid.

I scan in Adobe RGB 1998 on my Canon FS4000. I've had no problems printing wedding albums for a friend who scans his negs the same way on a Minolta scanner. He delivers his images to me on CD and I can print them straight off with no errors or fiddling necessary. I haven't done any calibration other than printing out a test image and varying the output until it looked right compared to what was on the screen. So professional !!

A lecturer showed us the colour space of some papers at a recent club night. Even the best ones can't reproduce half the Adobe RGB colour space so I wonder why we bother getting so excited about colour management !