QTR-Quadtone RIP

On 12-06-12 2:43 AM, "Ernst Dinkla" <e.dinkla@...> wrote:

> There could be two reasons for multiple measurements of the same
> density. The printer can be less consistent so you print more of the
> same patches to measure. The measuring can be inconsistent and measuring
> the same densities several times + averaging reduces the faults. The
> 21x4 target covers both. If both printer and measuring are consistent
> (for example measuring per patch) then there will be little gain by
> printing more patches and measuring them more times. With my old Epson
> 9000 custom quad printer + Spectrocam I used to measure strips of
> targets that were placed in different directions on the sheet.
> 
> Today with the Z3200 or the customised K5400 + an Eye 1 Pro, I use one
> 21 step target and reading per patch.

What I'm wondering is whether multiple prints, or multiple readings, would
net the largest benefit. The answer of course is, "it depends"!  ;-)

I obviously need to do some testing to determine whether my printer and/or
spectro are weaker links in the curve building chain.

> The QTR linearisation I
> put on top is based on the 21 step target but I think that the 34 step
> linearisation may improve on that. The same for the K5400 quad or
> tritone (gloss) that has ACV curves for partitioning.
> 
> Finished the 16-bit 34 step target some days ago, will put it into
> practice at the end of the week I hope. I will then add it to the
> targets for download on my site.

I am very curious to hear about how your testing with the 34 step target
goes. I am hopeful that it will help to minimize the "bumps" that can occur
during linearization.

Thanks Ernst.

Terry.