Re: Kodak IPB profiles
Re: Kodak IPB profiles
- Subject: Re: Kodak IPB profiles
- From: neilB <email@hidden>
- Date: Wed, 22 Nov 2000 11:24:37 +0000
Thanks for the help Steve,
On 21/11/00 at 5:09 pm, email@hidden (Steve Upton) wrote:
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At 12:57 AM +0000 11/22/00, neilB wrote:
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>Guys
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>We've recently had a couple of profiles made by a friend who uses Kodak IPB
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> 4.
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>We are aware that the black and white points of the scanned IT8
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>should measure at about 5 and 250. But whatever the endpoints of the
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>IT8 are set to when scanning,
[scanning the IT8 to make the profile that is]
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> say as extreme as 245 and 15, when the
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>scan is checked in Photoshop, the profile always maps the data right
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>up to 0 and 255 when we profile to profile the IT8 scan to test the
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>profile. Is this a Kodak IPB 4 feature?
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I think this can depend on the rendering intent you have chosen. If
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you are using Relative Colorimetric then you might see this as a
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natural mapping - into any color space.
I scan the IT8 keeping the data away from the endpoints and shooting for 250 and 5. My friend makes the profile from the IT8 scan. To test the profile I open the IT8 he used to make it, in photoshop - and I use the new profile as the source in a conversion to my workingspace.
When I open a levels dialogue box and option/alt click on the sliders for a "threshold" view I can see patches of the IT8 before I move the sliders inwards, which suggests to me that they are mapped up against the 0 and 255 points.
I have tried both the Colorimetric intents and Perceptual too, and the profile still maps some data, in the IT8 file I used to make it, to 0 and 255, which suggests a strong possibility of data clipping to me.
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Opinions?
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Steve Upton
I hope I explained it right.
neil
Neil Barstow
phone: 44 (0) 1273 774 704 fax: 44 (0) 1273 323 454
mobile: 44 (0) 77 78 16 02 01