QTR-Quadtone RIP

--- In QuadtoneRIP@yahoogroups.com, Ernst Dinkla <E.Dinkla@...> wrote:
>
> chiaro2112 wrote:
> > Hi Everybody Im a newbie in here, 
> > Sorry if my english is not very good, im also have question about QTR Create ICC/ICC 
RGB. I 
> > love this feature because finally im able to Soft Proofing Epson ABW.
> > If im not wrong (please correct me if im wrong), the function of QTR create ICC is to 
Linearize 
> > data and then make icc Profile based on linearize data. How if i want to make ICC 
profile 
> > without Linearized the data , so i can softproofing Before and after Linearize result in 
> > Photoshop? if it not posibble, There is another method for doing it?
> > 
> > Thanks Everybody,
> 
> 
> No, the QTR create ICC is to represent your printer output 
> in PS and adapt your image tone range to the tone range 
> possible between the Dmax and paper white of the paper you 
> made the profile for. You have to make or find a linear 
> output of your printer first.
> 
> Find an ABW driver setting that will deliver a linear 
> output. You can test that with the 21 or 51 step greyscale 
> targets. You have to check whether the Dmax doesn't run back 
> on the 100% patch compared to a lower one as that sometimes 
> happens. If the driver allows some ink limiting like my HP 
> Z3100 you can use that to bring the highest Dmax on the 100% 
> patch. Otherwise you could use the gamma function of 
> lighter/darker in the driver to make the output more linear, 
> a clumsy approach but there's no alternative. You have to 
> keep that setting then when printing later on.
> 
> When the printer's output is linear you can make the profile 
> with the same target.
> 
> For consistency in time you can not go back to a new 
> linearisation of the printer output like possible with QTR 
> or the internal calibration of the HP Z3100.  There's 
> Colorbase for calibrating some Epson wide formats but you 
> didn't mention the model.
> 
> If it is difficult to get the printer linearised you better 
> use the QTRip itself. A profile based on a non linear 
> printer output doesn't really help to get your shadows 
> correct etc. In that case you probably have more help from a 
> correction curve in PS if you want to stay with ABW.
> 
> 
> -- 
> Met vriendelijke groeten,  Ernst
> 
> 
> |  Dinkla Grafische Techniek  |
> |     www.pigment-print.com    |
> |             ( unvollendet )            |
>

Hi Ernst
Thanks For your detail Explanation, its very helpful info for me to find good starting point. 
I just experiment with epson ABW setting in my Epson Premium Glossy Paper and Ilford 
Smooth Pearl Paper. It seems difficult to find Linear result with ABW setting (from Light to 
darkest setting) in Epson Premium Glossy Paper. It always introduce Banding in Highlight 
area but the Dmax doesn't run back on the 100% patch . I believe Im already choosed the 
proper media setting for that. From 21 & 51 gray Target that i Printed out I see Obvious 
Color Shift in 25%( from 21 gray Target) & 24-28% (from 51 gray target).Before 25% and 
Toward 100% the patch are acceptable neutral. There is any Possibility to correct this 
(Color Shift) in Epson ABW setting?
Its very strange because it more easier to find Linear result with my Ilford Smooth pearl 
paper with Epson Semi Gloss setting and ABW dark setting. I think you're right about 
epson COLOR Base and maybe my printer behave differently than it used to be. Im already 
try download it but im just successfully got the Win XP version, The website (epson UK) 
didn't respond when i tried to choose Mac Os Version.
When you mention about Correction Curve in PS, are you mean Curve Adjustment layer or 
custom curve in dot gain setting?
Oh ya, i use Epson 4800 and it has color density setting is it same with ink limit feature in 
your hp driver?

Thanks Ernst and everybody
Davi Arzika