Re: Null Profile?
Re: Null Profile?
- Subject: Re: Null Profile?
- From: JWL <email@hidden>
- Date: Mon, 12 Nov 2001 14:48:01 -0800
Steve Upton <email@hidden> wrote:
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At 8:00 PM -0800 11/11/01, JWL wrote:
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>
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> What if I try to create a null input profile, though? Say if I edit a target
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> capture so that the patches are all the same as the lab values of the target
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> data file, then feed this to the profile creation software. Would the
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> resulting profile would be "null", having the same effect as not specifying
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> a source profile, i.e., no conversion?
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>
The target capture values are in RGB and the data file values are in
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Lab. There would be no way to edit the target capture values to be
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"the same".
-- I would convert the target capture to Lab, then edit, then back to RGB to
feed to the profiler.
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This also brings me to a point I've been meaning to post.
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There is, by the definition of how this stuff works, no such thing as
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a "null" profile when dealing with device profiles. Device profiles
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convert from Lab (or XYZ) to device space or device space to Lab.
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There is no way to create a profile that will have no effect (null)
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as it will have to convert from a colorimetric value to a device
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value or vice versa.
-- ahh! Thank you, Steve. I was hoping someone would respond directly to
the logic of this. I have been struggling to wrap my poor little head around
it. Really what I imagined was a way to achieve a "null" transform - so the
conversion from source input profile to destination working space gives the
same result as just grabbing raw data from the source.
Sounds like there is no way to build an input profile to have this effect.
However... any thoughts about that Flextight Input profile from Imacon, if
it was supposed to function that way (for scanning negs)?
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The only profiles that you could create as "null" are abstract
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profiles - like Lab->Lab or certain flavors of device link profiles -
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RGB->RGB or CMYK->CMYK
-- does this mean it could be possible to create a "null" RGB working space
profile? If so, how would one go about constructing it?
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Bruce's idea is probably your best bet ...<snip>...
-- Yes. Simpler, too! But I'm afraid that Andrew's right about Sinar's
software being broken, for color management purposes.
Thanks again for your insights.
Regards,
John