Digital BW, The Print

Roy & Steve,

Here is a color space converter calculator that will give you RGB or 
CMY from the LAB data (or XYZ), but not the same CMY density that Paul 
measures directly with the xrite.  However, Bruce Lindbloom does have a 
spreadsheet that will give CMY densities from the spectral data output 
of the eye-one.

http://www.easyrgb.com/calculator.php

http://www.brucelindbloom.com/

Carl

On Saturday, January 24, 2004, at 10:05  PM, Roy Harrington wrote:

>
> Hi Steve,
>
> It's certainly possible to measure a wedge printed out with any method.
> I'm also curious how to compare Paul's measurements to those I get.
> The trouble is he has c,m,y density values, and the eye-one gives
> Lab units.  It's similar tone info but I'm not sure how to convert
> one to the other.
>
> Roy
>
> --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Steve Kale"
> <stevekale@b...> wrote:
>> Thanks Paul.
>>
>> Can Eye One and, say, Measure Tool be used to measure this 
>> information by using
> the
>> QTR-21-Gray.txt step wedge file?  I guess that is another question 
>> for Roy or Carl.
>>
>> Cheers
>>
>> Steve
>>
>>
>>
>>> I use the difference between the cyan and yellow spectrophotometer 
>>> readings
>>> as a simplified measure of relative warmth or coolness.  If, for 
>>> example, Y
>>> is 0.60 and C is 0.55, I'd call the print warm by 5 units.  This 
>>> would be a
>>> typical medium warm, midtone reading.