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f90
14-Feb-2014, 23:15
Hi, I am a little rusty on the subject but from what I remember hearing on these forums a while back is that you could effectively print b&w up to 720ppi whilst using Piezography k7 and QTR combined. What I'd like to know is if there is the any way to print color at the same ppi? If not, has anyone tried printing the color without tone first, and then reprinting the b&w over the top with a peizography setup, which I'm guessing would achieve a similar result.

Any help would be appreciated, thankyou.

Ken Lee
15-Feb-2014, 07:45
It's the Quadtone RIP which allows the high resolution, not the choice of inks. The QTR also allows you to send 16-bit data to the printer (as opposed to Epson drivers which deal in 8-bit only). You can't make full-color images, but QTR does not require you to replace your inks, even though that might be a very good idea.

Tyler Boley
15-Feb-2014, 11:17
Well actually it's all of that and more. It's how the inks are designed in the first place, 7 distinct densities from light to black, then how they are utilized, which requires a driver capable of control of each ink, and then curves designed to control those 7 densities for the desired outcome. So QTR alone does not allow the higher resolution, you won't get that high using the OEM setups with QTR, but it does allow use of these special inks and the control through user curves to get there, the OEM driver won't quite do it. So the particular choice of inks are not solely responsible either, another well designed K7 set, and well designed curves to utilize them with QTR, could get you there too. NO single thing in this setup is responsible for the outcome, but each of those things is required.
Hope that makes sense.

Oren Grad
15-Feb-2014, 11:31
The OP is asking about printing color.


What I'd like to know is if there is the any way to print color at the same ppi?

Depends what you mean by "at the same ppi". If you check the "finest detail" box in the Epson print driver, it will send information to the printer at 720 ppi.

But the actual amount of detail the can be resolved in the resulting prints can be affected by many things, including especially:

* the hardware dpi setting (e.g, 1440x720 dpi vs 2880x1440 dpi; not all papers can accept the latter without getting into trouble, and there can be variation among samples of a given printer model in how much difference that setting makes)
* the content and tonal characteristics of the picture
* the paper you're using

It's not possible to give a hard and fast quantitative rule about the resolution that can be achieved. If you have something specific that you are trying to achieve you will need to run your own tests.

sanking
15-Feb-2014, 11:40
Well actually it's all of that and more. It's how the inks are designed in the first place, 7 distinct densities from light to black, then how they are utilized, which requires a driver capable of control of each ink, and then curves designed to control those 7 densities for the desired outcome. So QTR alone does not allow the higher resolution, you won't get that high using the OEM setups with QTR, but it does allow use of these special inks and the control through user curves to get there, the OEM driver won't quite do it. So the particular choice of inks are not solely responsible either, another well designed K7 set, and well designed curves to utilize them with QTR, could get you there too. NO single thing in this setup is responsible for the outcome, but each of those things is required.
Hope that makes sense.

I don't entirely agree with what you. In my own comparison tests I found that QTR with OEM inks does allow higher resolution than the Epson driver, "where" there is sufficient contrast. However, a multiple gray ink set (6, 7 or more shades of gray) allows for much smoother tones (and better detail), in the highlights and upper mid-tones of monochrome prints, with the right curve of course.

Sandy

Tyler Boley
15-Feb-2014, 19:31
actually that does make sense because of how the inks are used, even if OEM color sets. Since the RGB driver uses more inks than necessary to make a given gray, essentially a cluster of color and K (whichever or all) it has to throw out potential info, and I have to say, at least with the printers I've used, their dot clusters are pretty coarse. QTR with OEM inks and good setup and curves can use only the fewest required inks and lightest inks at higher dot frequency, until darker tones require darker inks.

f90
16-Feb-2014, 02:05
Thankyou for the info, much appreciated.