Ellie Kennard wrote:
> My printer has an "apparent" resolution of 1800 dip with a resolution

Ellie, dip is something you <dip> your crisps into if the seem a bit dry <G>

> of 600 dpi. I have usually sent files to this printer (handled by a
> RIP) at 300 dpi. I have noticed a certain blocking of some shadow
> detail, which I can view in my soft-proof.

>From memory you use a Rip and an Eye one, right?
If you have blocked shadows I'm 99% certain that it's a question of either
properly linearizing the RIP (ink limiting it) prior to profiling, or that
your source image has a black point that is darker than what can be
reproduced on the printer (you would need to use a colorimetric intent and
no black point compensation to have this second problem).

To figure out whether it's the first or second problem you have try this:
Convert an RGB test image (nick mine off <www.pixl.dk> if you want) to
"Euroscale Coatedv2.icc" using perceptual intent (or RelCol with Black Point
Compensation on in Photoshop) then save the image. Then convert this CMYK
image to your printer profile using RelCol with BPC OFF, and a copy with BPC
ON and print both.

If this first image opens up the shadows, and the second doesn't you are the
lucky winner of problem number two. To cure this you must print using
perceptual for everything (or RelCOl with BPC and convert everything in PS)
and live with the inability to do proofing. Alternatively find a different
paper that can yield a better black. This problem is usually apparent in
proofing where you convert CMYK images with a colorimetric intent.

If is a question of "less is more" (ink, not resolution) you need to limit
your inks even further prior to profiling. Call it linearization or
calibration. This is a complicated procedure and very hard to advice about
over email, check your RIP manual though. The problem is that many inks get
lighter when you increase the ink film, so more ink means lighter blacks,
and loss of shadow detail due to profiling application deficiencies.

> If I understand DM
> correctly, in his 'less is more' comment, it might be better for me
> to send the files through at 200 dpi instead. (other users of this
> printer have said they send through files at 200 ppi successfully.) I
> make my profiles for this printer from the (GM) target file which is
> the correct size at 300 ppi. Should I downsize this file before
> printing a target (down to 200 ppi at the correct size) to use?

Elli if you printed the profiling target at the resolution you usually use
you should be home free. While I'm very impressed with Dan's abilities for
colour correction images that appears to be beyond salvage (well beyond my
own abilities even after taking his course) this claim is cross to my
experiences with inkjets, and my experience in this area is substantial.
It would take a serious deficiency in the printers interpolation engine to
display this problem.

It is quite common for offset though! If you send a 600dpi image to offset
you may well get a slightly darker image, which is why it's very important
to know about quality factor and resolution. But for inkjet (especially in
the resolutions you are talking about) it's an entirely different ballgame.

Best Regards

Thomas Holm / Pixl ApS

- Photographer & Colour Management Consultant
- Adobe Certified Training Provider in Photoshop�
- Apple Solutions Expert - Colour Management
- Imacon Authorized Scanner Training Facility
- Remote Profiling Service (Output ICC profiles)
- Seminars speaker and tutor on CM and Digital Imaging etc.

- Home Page: www.pixl.dk � Email: th[AT]pixl.dk
-- 


===============================================================
GO TO http://www.prodig.org for ~ GUIDELINES ~ un/SUBSCRIBING ~ ITEMS for SALE

Reply via email to