Re: Decent results with Gutenprint - the poor man's RIP.
Re: Decent results with Gutenprint - the poor man's RIP.
- Subject: Re: Decent results with Gutenprint - the poor man's RIP.
- From: Graeme Gill <email@hidden>
- Date: Wed, 21 Jun 2006 14:40:42 +1000
Roberto Michelena wrote:
I believe BlackMagic's extreme is maybe too much... I wouldn't know
what to do with so many options! unless of course there's some
automatic "dot size mix optimization" method. Well, there could be, I
guess...
Yes, you can have too many knobs, if there is no way to know
how to use them. The manufacturers will have established
a workflow and set of tools they use to set these parameters
up. They may or may not make available this procedure and set of
tools to end users.
But I consider the "individual ink" linearization to be an advantage.
It can be more complicated than it appears. Some systems will
use independent screening for each ink. You can linearised
each ink independently on such systems. Some systems will
have an integrated screening algorithm for light & dark channels
(this is what Epson recommends for instance), and independent
linearisation isn't possible with such an arrangement. Such
a screening approach can end up being smoother, and having
more certain control over the total ink being layed down
in those combined channels.
Having the light ink separation pre-set by the manufacturer
isn't as bad as it might appear, as the characteristics of
the two channels tends to track, and it's overall characteristic
doesn't depend on the paper much.
One of the reasons (in my opinion) why linearization tends to be
insufficient to make any two printers match real close, is the
'canned' light ink mixing. If the Cyan max density can vary from
printer to printer, of course the Light Cyan max density can vary too.
And if you don't take that into account and make your mix always with
the same proportions (say 50%C = 60%Lc+ 15%C) you'll get hue shifts
because the light inks are usually a different hue from the dark ones.
I'm not sure this is that big an issue. While the hues are not
identical, they are close, and therefore any relative shift in
density causing hue shifts is diluted down. Shifts in the
combined transfer curve density will be corrected by
the linearisation.
Profiling N color devices is a whole lot harder to do right than 3 or
3 + black devices.
Graeme Gill.
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Colorsync-users mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden