Re: G7 press calibration, best press conditions or average?
Re: G7 press calibration, best press conditions or average?
- Subject: Re: G7 press calibration, best press conditions or average?
- From: Steve Miller <email@hidden>
- Date: Mon, 10 Nov 2008 08:54:22 -0500
- Thread-topic: G7 press calibration, best press conditions or average?
Thanks Mike,
That's a good explanation of the benefits of G7.
On 11/9/08 11:37 PM, "Mike Strickler" <email@hidden> wrote:
> Hi Henry,
>
> Several topics seem to have gotten conflated here. The question of
> the specialness of the G7 method has gotten tangled up with the
> question of the superiority of colorimetric methods, of which G7 is a
> subset. There is also the question of when and by whom G7 might be
> used. Separately:
>
> Densitometry is fine for process control, as has been stated, but
> pretty crummy for setting standards, as it doesn't dependably predict
> color appearance regardless of the sort of ink or toner used, as
> does L*a*b*, for example, which is inherently a measure of
> appearance. Where a system is already within ISO specs (ink, paper
> type/color) density specs already exist, and one could get by
> calibrating with a densitometer. That one can get by in certain
> situations is no reason to recommend it for general work. A trivial
> but common example of a shortcoming of densitometry is in adjusting
> for paper color. Even if you print to published specs (SWOP, Fogra
> 28, whatever) but use a paper of a different color (and who doesn't?)
> you must proportionally adjust the aim points of "neutral" CMY
> patches to toward the color of the paper, or the result will appear
> color-casted. With a spectro this is child's play, whereas with only
> a densitometer it is an indirect process at best. It is strange that
> people who accept and use colorimetry in the form of ICC profiles in
> every other area of color control would argue against it when it
> comes to this one particular output device, the offset press. It was
> one thing when spectrophotometers were simply too costly, but now?
>
> I don't particularly want pressmen worrying about L*a*b*. It's best
> to determine the densitometric aim points for their press and
> substrate and have them stick to them.
>
> G7 in particular: It's logical, straightforward, and fast (if one has
> the Idealink software). It's also flexible, easily allowing one to
> get the same ISO gray balance and very similar overall color
> appearance with different ink sets on different substrates, with
> systems of varying color capabilities and behaviors. What's not to like?
>
> Mike Strickler
>
> _______________________________________________
> 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
--
_______________________________________________
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