QTR-Quadtone RIP

Hi Babak,

I'm not Richard, but the densities entered should be those of the print, not of the negative. The goal here is to make a curve and/or linearization of the negative for your printing process, not to make a negative that is linear itself. 

It is also very odd that your negative densities would be not continuously increasing anywhere, so you have either a measurement error or a data entry error. In either case you should fix it manually. If print densities are not continuously increasing, it's a good idea to adjust them so that they are, otherwise your calculated Gray Curve will be wrong. 

Your negative Dmax is very low for Pt/Pd. I think this is due to the very low limit you have set for K. 

I would be happy to share with you my base curve for Pt/Pd (actually straight Pd) negs on a 3880 but didn't want to interfere with Sandy's and Richard's suggestions since it might add to the confusion. 

Cheers,
Keith

Keith Schreiber
jkschreiber.com




> On May 21, 2017, at 9:26 AM, fardy10@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:
> 
> Hi Richard
> 
> I am not sure if you are still following this thread, but having followed Sandy's instructions I am now at the linearization stage and thought of your software. 
> From what I understand in the  spread sheet for the negative density, in the column marked green I should enter the densities?? I presume these are the densities of the step wedge on the transparency (transmission densities), and not the densimetry of the printed stepwedge?
> 
> 
> I did this and got
> 
> 
> 0.0100
> 0.1400
> 0.0900
> 0.1200
> 0.1600
> 0.2000
> 0.2300
> 0.2700
> 0.3200
> 0.3600
> 0.4000
> 0.4300
> 0.4200
> 0.4800
> 0.5200
> 0.5500
> 0.5900
> 0.6200
> 0.6600
> 0.7000
> 0.7300
> 
> My d max appears to be very low and I am not sure what to do about that. 
> Is this the right path?
> THe other issue is having followed sandys text file, there is no grey_curve, but a CURVE_K="0;0 100;100" line. is this where the output should go? I am sorry if these are very basic questions with regards to this software.
> 
> 
> Babak
> 
>