QTR-Quadtone RIP

John,

That's basically correct but when I did the 2200 I found the biggest dot
outputing too much ink so I ended up using just the 2 smaller sizes.
The dropsizes are all very printer and resolution dependent -- they are 
all different.

Thanks for the link.  Looks like the R800 info.  Most of the other Epson docs are
very vague about drop sizes.

Roy

--- In QuadtoneRIP@yahoogroups.com, "John Moody" <moodymz3@y...> wrote:
> Roy,
> I thought the 2-bit VSD mode had three drop sizes?  The bits would be
> no-dot, 00, then 01, 10, and 11, right?
> It appears the relative drop size ratio is printer and mode dependant as
> well.  Some Epson stuff here.
> http://www.epson.co.jp/e/technology/sankei_4.htm
> 
> Best regards,
> John Moody
> 
> -----Original Message-----
> From: QuadtoneRIP@yahoogroups.com [mailto:QuadtoneRIP@yahoogroups.com]On
> Behalf Of Roy Harrington
> Sent: Saturday, August 20, 2005 9:48 PM
> To: QuadtoneRIP@yahoogroups.com
> Subject: [QuadtoneRIP] Re: QTR 51-step linearisation
> 
> --- In QuadtoneRIP@yahoogroups.com, "Tyler Boley" <tyler@t...> wrote:
> > --- In QuadtoneRIP@yahoogroups.com, Ernst Dinkla <E.Dinkla@c...> ...
> > snip...
> > > The targets you mention are the ICC profiling targets that usually
> > build
> > > on linearised inkchannels. Linearisation targets exist in many shapes
> > > CMYK-CcMmYK-Ncolor and they have ranges of 11 to 41 patches per
> > > inkchannel. the lowest number can be used for printsystems that
> > actually
> > > address the heads separately but on a CMYK driver that is linearised as
> > > CMYK but drives a CcMmYK printer it is better to use the 21 patches so
> > > there are 10 steps measured per head. With the 4800 that has 3Ks you
> > > could go up to 31 steps and that has been used for Colorspan models
> > that
> > > have 3 ink dilutions of CMYK each = 12 heads.
> >
> > My impression of the process is a bit different, correct me if I'm
> > worng. Individual ink components of a color, C and c for example, or
> > the 3Ks you mention, are generally not addressed individually in the
> > linearization process.  Some control is usually given with respect to
> > how the transitions will happen, but then the color (all inclusive
> > "C", or"K") is linearized as one. How exactly the total patch  count
> > may divide up between those indivicual components may not be very tidy.
> > I'm sure this varies from RIP to RIP. I recall Roy asking if we
> > thought there would be an advantage to individul ink linearization,
> > and wonder the same thing myself.
> >
> .....
> >
> > no doubt. But the partitioning step needs to be considered as a major
> > part of the overall performance picture. How many patches and how much
> > work needs to be done at the end can have a lot to do with how well
> > behaved the ramp is to begin with.
> > That few have trouble with QTR speaks well of Roy's existing
> > partitioning scheme. Setting it up to pull 7 inks in and out without
> > major problems must have been fun, or not!
> > Tyler
> 
> The 7 inks for K7 worked just fine.  The partitioning code has been the same
> since day one.  I thought about more levels of linearization but I'd
> probably
> do it after the partitioning rather that before with each ink.
> 
> But it's interesting that with the K7 inks its noticibly (but not much)
> better to use
> 2880dpi with only one dropsize rather than 1440dpi which is using two sizes.
> I think its because the 2X difference in drop size is as big as the
> difference
> between ink densities.
> 
> Roy
> 
> 
> 
> 
> 
> 
> 
> 
> 
>   _____
> 
> YAHOO! GROUPS LINKS
> 
> *          Visit your group " QuadtoneRIP
> <http://groups.yahoo.com/group/QuadtoneRIP> " on the web.
> 
> *          To unsubscribe from this group, send an email to:
>   QuadtoneRIP-unsubscribe@yahoogroups.com
> <mailto:QuadtoneRIP-unsubscribe@yahoogroups.com?subject=Unsubscribe>
> 
> *          Your use of Yahoo! Groups is subject to the Yahoo! Terms of
> Service <http://docs.yahoo.com/info/terms/> .
> 
>   _____