Re: Getting Dot Gain From Profile
Re: Getting Dot Gain From Profile
- Subject: Re: Getting Dot Gain From Profile
- From: Bill Birkett <email@hidden>
- Date: Thu, 15 Apr 2004 16:48:00 -0400
>
Could someone please post a method for determining the Dot Gain of a
>
profile?
Various people have speculated that this is possible.
However, it's actually not possible to compute dot gain (as defined
by industry standards) from the colorimetric data contained within a
profile.
It is possible to get an approximation of dot gain using colorimetric
reflectance values. But, the accuracy of that approximation may be
inadequate for some purposes. For example, here are some
Murray-Davies % dot values computed from the very same spectral data:
Patch Status T XYZ
50% K 77.2% 77.2%
50% C 71.0% 68.0%
50% M 73.9% 71.8%
50% Y 72.2% 73.5%
A 3% difference could be significant in some applications.
If you did all of your % dot measurements using colorimetry, you
would be fine, but most all published values are either Status T or E.
For the last 50 years, densitometers have been used in the pressroom
for process control. I doubt that will change anytime soon. The
fundamental problem for colorimetry in the pressroom is this: three
numbers to hit, but only one knob to turn :-).
-Bill
--
William B. Birkett <email@hidden>
Owner
Precision Color, Inc. -
http://www.pcolor.com/
9200 General Drive, Plymouth, MI 48170 (USA)
Phone: (734) 459-5640 FAX: (734) 459-4210
Cell: (734) 516-4790 Direct: (734) 414-3608
_______________________________________________
colorsync-users mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/colorsync-users
Do not post admin requests to the list. They will be ignored.