Gradient gaps rears its ugly head again

Gradient gaps rears its ugly head again

Post by lozz » Sat, 26 Mar 2005 02:37:20


From the previous topics I searched for on the subject of gapping between
gradient bands, I have yet to read an explanation that says why this happens.
My issue specifically is that often gradients exported to EPS then run through
Distiller to make PDFs exhibit gaps between gradient bands. These gaps actually
print and are noticeable on the final output (whether that be on-screen, offset
press or newsprint). What I don't is understand why this is happening. I can
have a document that has 2 identical gradients inside a rectangle (one created
by copying the other) and one will gap and one will not. Sometimes if I create
a gradient, then do not edit it, the gapping will not occur. Also I have
noticed that I can take a gradient that is exporting with gaps, modify it only
slightly in FH, and the banding dissappears in the EPS and PDF output! Since
there seems to be no rhyme or reason for this to happen, I can only assume it's
a program bug. Can anyone confirm this?
 
 
 

Gradient gaps rears its ugly head again

Post by Prepress P » Sat, 26 Mar 2005 03:25:49

to create an .eps save it as a freehand .eps instead of exporting. There is
better control of type and gradients in adobe programs this way. Take your
freehand .eps and drag it into distiller or adobe illustrator. In distiller you
can change it to a .pdf filtering it different ways, i.e. screen, press etc.
This can also make a difference in the quality of your pdf.

 
 
 

Gradient gaps rears its ugly head again

Post by lozz » Sat, 26 Mar 2005 05:41:26

http://www.yqcomputer.com/
created by saving the document as an editable EPS then rasterizing in
Photoshop: 25inches square at 200dpi. Notice that the gaps are not everywhere
in the gradient, suggesting a coding problem in calculating the change of the
FH gradient into Vector shapes in the EPS. Thanks for the suggestion, Pam, but
it looks like that doesn't fix the problem :(
 
 
 

Gradient gaps rears its ugly head again

Post by Judy Arnd » Sat, 26 Mar 2005 06:25:11


FH produces gradient steps that abut, not overlap. When Adobe products are
set to anti-aliase, they blur edges of the steps to background color (or
transparent).

Turn off anti-aliasing when you open the EPS in Photoshop. You can always
blur later if you need smoother edges.

Likewise, turn of anti-aliased preview in Acrobat.

Judy Arndt
 
 
 

Gradient gaps rears its ugly head again

Post by Bill » Sat, 26 Mar 2005 09:06:15

Perhaps that multiple fill capability might come in handy after all. I can't reproduce this behavior, but maybe if you try two copies of the gradient fill in the object, and offset the center of the lower one by with width of the gap or more, than the anti-alias will blend to that instead of the white background. Just a suggestion, since I can't try it myself.







--
Bill
FHMXa/WinXP/Athlon2500+/1GB
 
 
 

Gradient gaps rears its ugly head again

Post by lozz » Sat, 26 Mar 2005 13:10:40

Originally posted by: Newsgroup User


Likewise, turn of anti-aliased preview in Acrobat.

If only it was just on-screen, though. It prints like this, too.
 
 
 

Gradient gaps rears its ugly head again

Post by lozz » Sat, 26 Mar 2005 13:15:16

Thanks for the suggestion, Bill. That sounds like it may work. Another FHMX hoop to jump through :) Are you using a PC or a Mac (having the problem in OSX am I)?
 
 
 

Gradient gaps rears its ugly head again

Post by Judy Arnd » Sat, 26 Mar 2005 15:59:12


Are you printing an EPS directly to a Postscript printer, or are you
printing the after another program has rasterized it? If you place the
EPS in a FH document or a page layout program (e.g. InDesign or
QuarkExpress) do you see the gaps when printing to a Postscript printer?

Judy Arndt
 
 
 

Gradient gaps rears its ugly head again

Post by lozz » Sat, 26 Mar 2005 17:05:55


on-screen, though. It prints like this, too. Are you printing an EPS directly
to a Postscript printer, or are you printing the after another program has
rasterized it? If you place the EPS in a FH document or a page layout program
(e.g. InDesign or QuarkExpress) do you see the gaps when printing to a
Postscript printer? Judy Arndt Judy, I'm just exporting to EPS from
FreeHand, then creating a print-ready PDF from Distiller, then printing the
PDF. It prints with bands on our Minolta copier/RIP and on the offset press of
our direct mail company. The worst case was on a doorhanger for a client. The
exact same gradient was on both sides (copy/paste or more likely copied the
page with the page move tool), and one side printed all the ugly gaps (This is
what leads me to believe it's some sort of FHMX glitch ). I didn't zoom in
close enough in Acrobat to discover the problem or print a full-size final from
the PDF. Fortunately, the client was oblivious! Anyway, PDF is the final
output, but I can also see the gaps in Illustrator when opening the original
EPS or distilled PDF. The gaps are also inconsistent - they often appear only
in certain parts of the gradient. Many times I have no problem with the
gradients. Also, I am aware that if you zoom in close enough you will always
see a small gap (or at least it appears so on-screen) between bands, but these
are larger ones that show up in the final output. Weird.
 
 
 

Gradient gaps rears its ugly head again

Post by Bill » Sun, 27 Mar 2005 02:47:16

I am using a PC. I have seen inexplicable banding in rasterized gradients, but I have not seen the background-color striping that you are experiencing.






--
Bill
FHMXa/WinXP/Athlon2500+/1GB
 
 
 

Gradient gaps rears its ugly head again

Post by Judy Arnd » Wed, 30 Mar 2005 03:28:46


What is the width (in points) of the gaps you're seeing? The only gaps I
have seen in gradients exported from FH are in the range of 0.02 point, less
than one tenth of a hairline stroke. On a traditional press with wet ink,
ink spread would more than take care of any gaps.

Is the RIP a Postscript RIP? It sounds like Acrobat is sending an
anti-aliased view to the Minolta copier, and that's why you're seeing the
gaps. Try this when printing from Acrobat and see if it helps. Uncheck:

Preferences > Smoothing > Smooth line art

Judy Arndt
 
 
 

Gradient gaps rears its ugly head again

Post by KV_man_7 » Sun, 03 Apr 2005 05:57:20

I have this problem to , with a specific Logo i have created.

What I do whem it starts to apear : I place a new Original of the Logo and it
works.

But if it not work , I put all things on a new Document an "voil?" (copy and
paste)

Mac os X (10.3.8) Distiller / Acrobat 6.0 / Lintronic PPD

I think the problem is the diferent way adobe products work with the
gradients, its look familiar whith the .ai export of gradient object (every
body knows what happens)

ps. try to fix in 256 steps the post script output

ps2. the little gaps not apear in high resolution outputs , but the big ones
.....

LSA from Brasil
 
 
 

Gradient gaps rears its ugly head again

Post by lozz » Sun, 03 Apr 2005 08:46:54

Originally posted by: KV_man_73 I have this problem to , with a specific Logo i
have created. What I do whem it starts to apear : I place a new Original of
the Logo and it works. But if it not work , I put all things on a new Document
an 'voil?' (copy and paste) Mac os X (10.3.8) Distiller / Acrobat 6.0 /
Lintronic PPD I think the problem is the diferent way adobe products work with
the gradients, its look familiar whith the .ai export of gradient object (every
body knows what happens) ps. try to fix in 256 steps the post script output
ps2. the little gaps not apear in high resolution outputs , but the big ones
..... LSA from Brasil Thanks. There are other bugs like this in FHMX that
can be fixed by simply duplicating your object (or cut/paste). I can usually
fix the problem by altering the gradient only slightly (moving a color stop,
etc.). It's just a pain to have to check every gradient in Acrobat at high
magnification for these odd gaps. Especially problematic are gradients that
span large areas (15-25 inches). These larger-than-normal gaps are not always
visible when zoomed at 100-200% in Acrobat, but are very noticeable when the
output comes back from the press.
 
 
 

Gradient gaps rears its ugly head again

Post by lozz » Sun, 03 Apr 2005 08:54:05


to EPS from > FreeHand, then creating a print-ready PDF from Distiller, then
printing the > PDF. It prints with bands on our Minolta copier/RIP and on the
offset press of > our direct mail company. What is the width (in points) of
the gaps you're seeing? The only gaps I have seen in gradients exported from FH
are in the range of 0.02 point, less than one tenth of a hairline stroke. On a
traditional press with wet ink, ink spread would more than take care of any
gaps. Is the RIP a Postscript RIP? It sounds like Acrobat is sending an
anti-aliased view to the Minolta copier, and that's why you're seeing the gaps.
Try this when printing from Acrobat and see if it helps. Uncheck: Preferences
between bands you get when zoomed into a gradient (when viewed as PDF in
Acrobat or EPS in Illustrator) at maximum magnification. Those gaps don't print
and have been a part of the FH-to-Illustrator-and-back round trip that we've
had for years. These gaps are not uniform in size to every band (and do not
appear on every band) and can be seen well before maximum Acrobat
magnification. Take a look at the screen-shot of a rasterized FHMX EPS I posted
as it's exactly what happens in Distiller and Illustrator when viewing FHMX
exported gradients (for me) - I'm sure you'll see that this is not the normal
gaps we know are always there.