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View Full Version : Achieving accurate Kodachrome color reproduction without calibration target...?


KodaMan
01-08-2012, 10:47 AM
Howdy guys.

Recently I've been considering scanning my collection of Kodachrome slides. You all know that Kodachrome is challenging to digitaze, mostly because of the tendency to scan with the blueish cast.
Using color calibration with a Kodachrome target solves the problem, but...

1) ...calibration targets are very expensive, making calibration a significant investment...

2) ...my collection is very small, which makes buying the target even less sensible.

So, here's my question: is it possible to achieve accurate color reproduction without calibration? For example - is it possible to 'copy' the calibration files from somebody who calibrated his scanner?
Has anyone here ever used calibration with Kodachrome?

I'm using CanoScan 8800F and Silverfast.

Cheers!

kevinkar
02-17-2012, 10:33 AM
I have. I bought the Silverfast calibration target. It does indeed help. It's not foolproof though. It sometimes fails to generate proper output resulting in additional fiddling and correction. That's why I also use Vuescan Pro which sometimes produces better output.

Theoretically you could use a calibration profile from someone else but that's output derived from THEIR scanner and would not correctly match yours. It might be close if the scanner is the same make and model but, otherwise, you'd have to fiddle with the results as well.

I did once try to use Vuescan to generate a profile and apply it in Silverfast but that did not work.

In lieu of calibration, you could take a stab at adjusting the input/output curves in Silverfast and saving that profile as a best guess that might be consistent from slide to slide but that does not guarantee it will work picture to picture much less roll to roll. It's better than no correction at all.

There are methods on line to create your own calibration profiles but I found them a bit too involved for my tastes. You could look for them.

Otherwise, the only way to work the issue is a lot of fiddling with settings for input and correcting the output as you go which will add considerably to the amount of time you'll spend. You could scan everything in pure RAW mode to capture just what the scanner sees and subsequently adjust levels in a batch mode later so you might be able to get the base scanning all done and worry about adjusting the results later.

No matter what, it's not easy!