Re: A Profile's Curve Shape
Re: A Profile's Curve Shape
- Subject: Re: A Profile's Curve Shape
- From: Thomas Holm/pixl <email@hidden>
- Date: Tue, 18 Jul 2006 13:37:32 +0200
On 18/07/2006, at 4.27, Bill Whitfield wrote:
Greetings,
Does the shape of a profiles individual color's curve as viewed
under Dot Gain in Measure Tool affect the integrity of the profile?
Measure Tool supplies a few sample curves and they have a very
uniform (smooth) shape. The curves for my press CMYK when compared
to the sample curves are very "wavy" with bumps and valleys (real
technical, I know). Does this make the profile "work harder" to
create a good proof?
It means that probably your target was printed unevenly and
measurements therefore are skewed. This will basically make the
profile somewhat less accurate and will possibly give you
posterization and banding on press but not on proofs (if you use the
same profile for proofing).
You need to maesure multiple targets placed in different areas of the
press, rotated differently. Thne measure these and average them and
rebuild your profile. And you need to make sure the press is run
within very strict limits in regard to Density across and down the
sheet. Being on flexo that's a pretty costly process to redo.
Alternative you need to smooth out the target data prior to building
the profile.
I know with a little work on my curves (I am a flexo printer that
needs a compensation curve so my 50% prints near a 70%) I can
create a smoother curve.
The curve you see in measuretool are only pure CMYK curves. You are
likely to have even more severe problems in composite colors
.
Is smoothing out my curve worth my effort, actually not so hard for
me to create the curve, just a challenge to get press time to print
and test them, or will a proofer be able to match my press profile
as is, just as well as if the curve was smoother? Somehow I feel
the smoother the curve the better, but I have no facts or any
offset profiles I can look at to see how smooth they are.
Bill, try and send me the measurement data (not the profile) offlist
and I'll have a look.
Best Regards
Thomas Holm / Pixl Aps
- Colour Management Consultant
- Seminars speaker and tutor on CM and Digital Imaging etc.
- Apple Solutions Expert
- Member, ColorManagementGroup.com
- www.pixl.dk ยท 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