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jev
07-07-2010, 5:07am
I used a lens last week that creates rather flat looking images with some rather pronounced colour shifts. Of course, I can fix that in postprocessing based on a grey card and using curves, but that's rather tedious and not very accurate (read: I'm lost, can't get good looking results).

Now, it would be great if I could create a custom input colour profile that already . I found software (lprof) that can create a colour profile based on images shot from an IT8 reference target. I know you can buy these but darned they are expensive!

Now, since I've got quite a good and calibrated printer setup, I thought it should be possible to actually print the IT8 reference myself. I can't find any synthesized and printable IT8 JPEG or TIF files though. Anyone have one that (s)he is willing to share?

ricktas
07-07-2010, 8:53am
Hmmm. Good question Jev (how are you?). I too have seen them and agree $$$, but have never seen a printable one either. Hope someone can help, as it could be worthwhile for quite a few members.

arthurking83
07-07-2010, 10:14am
define expensive?

color.de seem to have reasonably priced IT8 charts, but I'm assuming you want film neutral colour chart, such as the LaserSoft digital version.( 59 or 79 Euro). To me that sounds expensive, but it's not calibrated for any particular film type, which are expensive at 200+ Euros!! :eek:

I've found various images of IT8 charts, but all are very low res, and I wouldn't rely on them for calibration purposes..

Check THIS (http://photo.bragit.com/scanning/it8tests.shtml) website and look for the link to Comparisons using the IT8 target(there are many) and it links to a few test images of a target calibrated via the various software on trial on that site.

Also via that website there is a link to a GNU software site called 'scarse' a free scanner calibrating software. That chap had 140Kb tiff image of an IT8 target both calibrated and not calibrated.

I've never used them, never downloaded them. I bookmarked many sites long ago as I was looking for info on colour calibration for a batch of old photos I scanned for my mum. Haven't clicked on any of them since then(over a year ago).

Hope any of that info helps.

I was just thinking too tho. It'd be a lot of work for a non PS person like me, but how hard would it be to create a synthesised IT8 target using PS. If the data for each colour block is available as common knowledge(ie. free!), it shouldn't be hard for someone that knows how to use the program to create their own digital version rather than relying on a manufactured version.
of course I make those comments as someone with very limited PS knowledge!

jev
09-07-2010, 1:17am
Thanks guys. Indeed, I don't want any calibrated for a specific type of paper, I need a generic one that I can print (so preferably including a standard colour space). I'm aware of the fact that this probably isn't as good as calibrated printed outputs that one can buy for $100+ prices, but it's just for experimental purposes - good enough is good enough ;).

@Arthur: I found the same sites you mention, didn't think to download the software but you may be onto something - the charts just may be included!

The patches unfortunately are not available in the public domain afaik, they are part of an ISO standard these days. I'll keep searching though because it really shouldn't be too difficult to create a chart in PS.

@Rick: thanks for asking, things aren't looking good at the moment I'm afraid. Just returned from a short trip to Sicily which we had to cut short and not much photography going on at the moment. Hopefully things will improve over time.