Author Topic: Here is the ghostscript questions Andy!!  (Read 10439 times)

Offline Gilligan

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Here is the ghostscript questions Andy!!
« on: November 12, 2011, 10:29:13 PM »
Actually haven't even got there.

I'm following a tut on t-shirtforums and they say to install a laserjet 4/4m PS and "print to file".

seems easy enough.

Set it up, test file works (doesn't ask me where to save but a quick search and I find it saving to my profile's root)... so off to Photoshop.

Go through the motions and ... and... and... NADA!

No file created and no error.  This is on my XP laptop... on the wife's win7 64 desktop it says "access denied" when I select the file name (from any app).  Probably a UAC issue trying to write to the root of my profile.  I would like to specify where my file would go but I don't seem to be given that option.


Offline Gilligan

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Re: Here is the ghostscript questions Andy!!
« Reply #1 on: November 12, 2011, 11:26:48 PM »
So more playing around.

Still no luck with Photoshop.

BUT Illustrator does output separations and outputs to file (I need a better printer to fake I think).

So I took my blocks and dumped them into illustrator and outputted them... now I'm confused.  Maybe this is how it is supposed to look but it seems odd.

This is blocks of 90% black to 10% black.  I printed out of ghostview to PDF so I could look at the dots close up.

Can someone explain them better to me or is it like I think and screwed up?

Offline Frog

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Re: Here is the ghostscript questions Andy!!
« Reply #2 on: November 13, 2011, 02:01:34 AM »
I rarely output this stuff from Photoshop, but rather Corel, mostly DRAW. There we have an option to output as a Device Independent Bitmap.

Forgive me if I screw this up, because as I said, I hardly ever output this way. However, there are a bunch of other members who will explain this better (if not actually correctly if I blew it)

In Photoshop, I guess I would print to file to a dummy driver, as you did. I use the HP 5500 In Photoshop, you set your lpi, and angles in each channel (just black in this case)
Print to file, then, you need to open Ghostview GS View. This is where you actually print from. I saw no mention of this, do you have it installed?
If not, get it here.
Open your file, set your media size (and orientation if needed), pick your real printer, and have at it.
That rug really tied the room together, did it not?

Offline Gilligan

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Re: Here is the ghostscript questions Andy!!
« Reply #3 on: November 13, 2011, 10:46:06 AM »
Ok... still not working form Photoshop.  Same thing... looks like it's making the file but it disappears, never ask where to save it and it's no where to be found in a search of the hard drive.

I do have Ghostview (and ghostscript).

That pdf I attached above was from printing to PDF from ghostview (as a way to see the output, I don't have a printer at home).  That was from the LaserJet 4/4M PS which resulted in strange "ellipses" to say the least.

So I grabbed the 5500 and installed it.  From here I went back into illustrator and still had some problems if I choose "Separations (host based)" from the output section it was printing in a weird CMYK that was using all colors (like when working in RGB how black isn't just black but a mix)  I outputted the sep and turned off all the other colors and it just had like the darkest blocks.  So I tried "In-Rip Separations" (this wasn't available in the LJ 4/4m) and it worked just fine.  Even made better ellipses as you can see from this attached PDF printed out from GhostView.

So should I be able to take the .ps file that created this pdf and use ghostview to output my films for my halftone test?  Hoping to get some testing done today. :)

Offline Frog

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Re: Here is the ghostscript questions Andy!!
« Reply #4 on: November 13, 2011, 11:24:07 AM »
As I warned you, I am not the guy for much help with specific Adobe/Ghost questions (hell, I'm barely helpful with Corel)

An Adobe Ghoster is bound to jump in.

A couple of things though. When I tried this in PS last night, I also could not find my saved "Print to File" file. I did a search, and did find it in my usual "Frog Jobs" folder (rather than the usual  "Print to file" folder I have).  Make sure you give it a specific individual name that you can search for, and figure out where PS and GS View want to put them.

Then open it in GS VIew and print.

Now, In PS or Illy, what line frequency did you use? The 40 that we suggested? I can't tell from your attachment, as except for bitmap workarounds, the line frequency is a product of the RIP upon output.
That rug really tied the room together, did it not?

Offline tpitman

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Re: Here is the ghostscript questions Andy!!
« Reply #5 on: November 13, 2011, 12:43:25 PM »
I'm using CS5, and I know a few things have changed, but . . .
Bring up your print dialog box, make sure your fake postscript printer is selected, and that separations are selected. Older versions of Photoshop allowed a bit more customization here than 5 is allowing, but you should make your frequency, dot shape, and screen angle here.

Look for a "Printer" button at the bottom of the print dialog box. If you click on it, you should get a drop down menu of choices, such as "save as PDF" and "save as postscript" . . . select "save as postscript" then the Save button. You should get the option of where to save it.
When you close that, you might have to re-enter your linescreen/shape/angle choices (for some reason I always had to), and hit Print.

Obviously, open the .ps file you just saved and have a go at it. As Andy pointed out, make sure your media size matches the "sheet" size of your original file and of the fake printer, otherwise things have a way of getting cropped out.

It's a squirrelly program, but it's free and does an excellent job once you've run the obstacle course and figured it out.

Hope this helps. I've had issues since moving up to CS5 and OSX Snow Leopard. Under CS3 I always used the Adobe PDF printer that was an option and allowed for any size output, plus all of the halftone options. I hate it when things get "fixed" . . .
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Offline Gilligan

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Re: Here is the ghostscript questions Andy!!
« Reply #6 on: November 13, 2011, 01:22:48 PM »
Ok, I'll clear up any thing confusing hopefully.

Photoshop, yes, it just disappears and I named it a unique name to search... I am a computer guru so I do know how to search my computer and make sure I find what I'm looking for.  Just not there... it acts different than Illustrator in that it puts up a dialog box asking for file name, not a usual save as dialog box.

In Illustrator, I'm using 40 lpi and 45 degrees ellipse (left it 45 just because it's one color).

Ok, out the door real quick... will fill in more later... CS4 btw.

Offline Frog

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Re: Here is the ghostscript questions Andy!!
« Reply #7 on: November 13, 2011, 02:29:23 PM »
Just a note, though you may do fine with 45 degrees, the need for the neutral angle in this case is not interaction with other colors, bur rather interaction with the mesh itself.

For this test, it's no biggie, and in fact could prove very educational.
That rug really tied the room together, did it not?

Offline Gilligan

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Re: Here is the ghostscript questions Andy!!
« Reply #8 on: November 13, 2011, 02:59:08 PM »
Ok, so back (had to go eat lunch with the family)...

So OK,  Created blocks in a CMYK document in photoshop (0,0,0,90 then 0,0,0,80 and so on).  Merged visible and copied and pasted to a CMYK illustrator doc.  Then printed to "fake" printer (designjet 5500 PS 42in), using "In-rip separations" and unchecking all the colors except black.  Setting 40 LPI, 45 degree, ellipse.  Save as dialog box pops up and I save the file "blocks5500.ps" then open up that file in Ghostview and print it out to a PDF printer so I can verify the halftone images.

That is what I've posted right there in the last attachments.

Does that all look like it should?

Offline Frog

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Re: Here is the ghostscript questions Andy!!
« Reply #9 on: November 13, 2011, 03:26:59 PM »
At least what I get is halftones, but at my printer's defaults.

As Tom said, save your file as a postscript file. That is where the magic then occurs in Ghost and GS View.

That rug really tied the room together, did it not?

Offline Gilligan

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Re: Here is the ghostscript questions Andy!!
« Reply #10 on: November 13, 2011, 03:34:05 PM »
Ok, I don't get the options that Tom mentioned.

I just get a standard printer dialog box.  I print and it pops up a "save dialog box" like if you hit save on a document in an application.

This is when I go to "file" > "Print" then hit "print".  I assumed that that IS a post script file... but I want to move beyond "assumption" and KNOW I did it right.

Offline Frog

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Re: Here is the ghostscript questions Andy!!
« Reply #11 on: November 13, 2011, 03:42:34 PM »
You'll get more Photoshop and Illustrator-specific members chiming in later today, or even more tomorrow, I'm sure.

Me, I have 50 hoods to do right now!
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Offline Gilligan

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Re: Here is the ghostscript questions Andy!!
« Reply #12 on: November 13, 2011, 05:47:45 PM »
Ok... Illustrator on 7 is being silly.  The option for separations on the 5500 is greyed out.  Unless someone knows a trick I'm looking at the Adobe PS driver.  Does that work all the same?

Seems like it does but I really don't know.

I've made a large gradient bar going from 100% to 0% and marked it at every 10%.  I'll be adding some squares of said mile stones and printing that out.

Offline Gilligan

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Re: Here is the ghostscript questions Andy!!
« Reply #13 on: November 13, 2011, 07:02:48 PM »
Ok... little progress.

In-Rip sucks with the new windows 7 5500 driver.  Host based is the way to go here. (technically I'm  using the Adobe Postscript file with the 5500 as the PPD.)

Here is the PDF of the latest test.  I also printed out a real page test on plain paper and it looks essentially the same... to the naked eye that is.

Is this the type of halftones I should be expecting out of ghostscript or am I missing something?  It's definitely better (cleaner) than doing the bitmap trick in photoshop... makes that look like a joke.

Is this what 40 lpi 45 degree ellipse halftones should look like I guess is what I'm wondering?  And now on to the $800 dollar question.  How much better (if any) would this look coming out of Accurip?

Offline screenxpress

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Re: Here is the ghostscript questions Andy!!
« Reply #14 on: November 13, 2011, 07:32:22 PM »
Excerpted from my complete write-up on Ghost -

***********
PHOTOSHOP
***********
- Photoshop - finish any separations for halftones to where you have the channels ready to go 
   Click File - Print Options - SCREEN and set the lpi, angle, and shape for each color channel
      Note for CS2 this is found in Print with Preview - If you don't see these setting, be
      sure your setting is for "Output", NOT "Color Management" 
   Select PAGE SETUP to point to HP DesignJet 5500 and click OK
   Select one channel to print and click PRINT.  If a message pops   up that clipping might occur, just click PROCEED.  If a message pops up for resolution higher than 2.5 times the frequency, just click PROCEED 
   Click the box for PRINT TO FILE and click OK.  The PRINT TO FILE box should open wanting an Output File Name.  I have a folder on my C drive named "GHOST", so what I put in the box is - C:\GHOST\xxxxxxx_yyyy.ps where xxxxxxx is my customer and yyyy is the color of the channel.  So name it something like C:\GHOST\Cust_Image_Color.ps and click OK.  Note those are "back slashes" (above the Enter Key), not "forward slashes".  The channel will output to where you referenced.  It may take
      20 - 45 seconds to output and Postscript files can be quite large 
   Repeat the steps for each channel


DesignJet 5500 is a postscript driver set.  You MUST have a postscript driver installed to be able to write to a "file".  However, you do NOT have to have the physical printer.

I'm having trouble finding those options in PS CS5.  In previous versions you had the option to click on "write to file" box.  I'll keep looking.

Tom, in CS5, I do not have an option in the drop down for "save as postscript"
« Last Edit: November 13, 2011, 08:30:51 PM by screenxpress »
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