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Hello Everybody

2018-08-30 by mangini.lorenzo@...

Hello from Firenze, Italy. Just discovered this group and I'm glad to be part of it. I'm studying, yet, what QT is able for and what it can do. I'd have many questions to ask you Masters, but the first one is: is there a way to connect the a/b channels readings with spectrophotometer with a Photoshop curve that can be loaded into the Toner/Toner 2 curves to balance the interactions of blacks, using K3 colour inks? I mean, exactly: if I have a certain reading of, for instance, -2,35, how can I translate that value in a Photoshop curve or ATF file so that I can load it up to the LM channel to counteract the cyan shift?

Thanks and Happy Printing

Lorenzo

Re: [QuadtoneRIP] Hello Everybody

2018-08-31 by Simone Simoncini

I think the easiest way would be to make an icc profile with your spectrophotometer. In one of my printers, the hpz3200, there is a built in spectro and is very straightforward. I guess this is what spectrophotometer are made for (at least in the printing industry).

Qtr has a way to make either rgb or bw icc profiles. I use qtr and print tool with the epson 4800, though mainly for digital negs.

Nice to see there is someone else from tuscany.

Ciao

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Il gio 30 ago 2018, 22:27 mangini.lorenzo@... [QuadtoneRIP] <QuadtoneRIP@yahoogroups.com> ha scritto:

Hello from Firenze, Italy. Just discovered this group and I'm glad to be part of it. I'm studying, yet, what QT is able for and what it can do. I'd have many questions to ask you Masters, but the first one is: is there a way to connect the a/b channels readings with spectrophotometer with a Photoshop curve that can be loaded into the Toner/Toner 2 curves to balance the interactions of blacks, using K3 colour inks? I mean, exactly: if I have a certain reading of, for instance, -2,35, how can I translate that value in a Photoshop curve or ATF file so that I can load it up to the LM channel to counteract the cyan shift?

Thanks and Happy Printing
Lorenzo

Re: Hello Everybody

2018-08-31 by mangini.lorenzo@...

Thanks Simone, I'm glad too :)

The matter is all about controlling the whole process; an .icc profile, as you know, is a passive command on colours. Though I use .icc profile for colors (I use an old version of EFI with ECI RGB charts and a Pulse), for BW prints with K3 inks I absolutely prefer QTR. It is a real RIP on the fly and it leaves total control over inking.

I figure you know what I mean: different papers behave differently under certain lighting conditions, and the Toner control lets you balance the warm/cold tone respecting crossing tonal values. This is a great advantage.

QTR does not fix a white point, an .ICC profile has a fixed white point.

Toning inks (LM/LC) let you decide whether for cold, whether for warm prints. Adding a bit of yellow or cutting black tones and Bòack boost introduces sepia toning. And this you can do directly. I sometimes make use of Epson ABW, for which I have a whole process using Duotone curves (.ATF file I add to final image before printing), but QTR behaves better, I think.

So, finally, my trouble is relating the Gray Curve and the Linearized L values with a simple curve in Photoshop, a curve that I can upload to the single Toner mask to balance the warmth or coldness of L line.

Hear you soon,

Lorenzo

QTR-Quadtone RIP

Hello Everybody

Hello Everybody

Re: [QuadtoneRIP] Hello Everybody

Re: Hello Everybody

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