Synth-DIY Yahoo! Groups Archives

QuadtoneRIP Curve Blending

2016-05-28 by dagor52@...

I'm using MIS UT14 Inks and printing with a Epson 1400. I'm using Windows 7 and QuadtoneRIP's latest version. My work flow involves an Excel Spreadsheet to plot my densities and I measure them with a Data Color SpyderPRINT spectrometer.

So, I've made two Ink curves, Cool and Warm. Both of these curves work perfectly when used by themselves (un-blended). The measured the densities on prints of the standard 21 Step ramp and the density values are a perfect match when plotted in Excel and compared to the Ideal Dmax Values. I've done this with both the Cool and Warm curves that I've made with no deviations in the curve densities between the two curves.

The problem that I'm having is when using QuadToneRIP's Curve Setup and blending my two curves. My first Blend was a Cool 50% and Warm 50%. The resulting print made of the 21 Step ramp shows a drop in the curve around Step 80 for the combined curves. I've gone through the process several times hoping to find my error, making new Cool and Warm curves, but the results are always the same. Can anyone give me some help here....or is this just an issue that is inherent with blending to curves? It would make sense to me if my Warm and Cool curves were not a perfect match to both each other and the Ideal Dmax values, but this is not the case. Thanks in advance for any suggestions as to what I'm doing wrong.

Re: [QuadtoneRIP] QuadtoneRIP Curve Blending

2016-05-30 by Roy Harrington

Usually blending gives pretty accurate density consistency. But there aren't any builtin

guaranties since there are so many variables -- inks, dot sizes, etc.

I think the best solution is to make an additional curve for neutral -- basically your 50/50 mixture.

That way for the future you can have mostly neutral and blend only smaller amounts of the warm

or cool to tint your prints. (this is what I've done for a number of the newer printers & curves)

Roy

Show quoted textHide quoted text

On Sat, May 28, 2016 at 9:12 AM, dagor52@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> wrote:

I'm using MIS UT14 Inks and printing with a Epson 1400. I'm using Windows 7 and QuadtoneRIP's latest version. My work flow involves an Excel Spreadsheet to plot my densities and I measure them with a Data Color SpyderPRINT spectrometer.
So, I've made two Ink curves, Cool and Warm. Both of these curves work perfectly when used by themselves (un-blended). The measured the densities on prints of the standard 21 Step ramp and the density values are a perfect match when plotted in Excel and compared to the Ideal Dmax Values. I've done this with both the Cool and Warm curves that I've made with no deviations in the curve densities between the two curves.
The problem that I'm having is when using QuadToneRIP's Curve Setup and blending my two curves. My first Blend was a Cool 50% and Warm 50%. The resulting print made of the 21 Step ramp shows a drop in the curve around Step 80 for the combined curves. I've gone through the process several times hoping to find my error, making new Cool and Warm curves, but the results are always the same. Can anyone give me some help here....or is this just an issue that is inherent with blending to curves? It would make sense to me if my Warm and Cool curves were not a perfect match to both each other and the Ideal Dmax values, but this is not the case. Thanks in advance for any suggestions as to what I';m doing wrong.

Roy Harrington
roy@...
www.harrington.com

QTR-Quadtone RIP

QuadtoneRIP Curve Blending

QuadtoneRIP Curve Blending

Re: [QuadtoneRIP] QuadtoneRIP Curve Blending

Move to quarantaine