Will an inkjet proof show trapping ??

[imagesetting]

Hi,
I am looking to create Press Ready PDF's with trapping.
We used to produce punched film separations, and a Cromalin Proof. With an eye glass you could see the trapping and check it.

Firstly can you rely on Adobe CS Auto trapping (I believe InDesign can do this) or should you do it manually.

Second, before going to plate (CTP), what is the best method for checking trapping - a soft proof on screen, or with an inkjet (I'm assuming an Epson has the resolution - please advise).

[M. R. Horton]

I want to look at the same dot structure as what is going to press when proofing traps, so in our shop "soft proofs" are closer than our inkjet proofs, and there are more options for viewing separations and zooming in.

[imagesetting]

Thanks for the reply, can I ask what inkjet printer your using.
When you say dot structure, I assume you refer to the screened dot structure (ie 150lpi or 200 lpi), and not the resolution of the output device (ie 1270 or 2540 ... as an example).

[buckeye]

imagesetting,

Yes, an inkjet proof will show, to some degree, trapping. It will not come close to a monitor/soft proof's preview of trap though. I can SEE traps on our Epson 9900 proofs, which we output at 720 dpi, but I always rely on our monitor proofs which are generated from Rampage.

[Colorblind]

Same thing here on my ApogeeX workflow to Epson 9800, trapping will show on the proof, at least at 720 dpi. But as buckeye mentioned, since trap zones are usually very narrow, the resolution of the printer will limit the thickness accuracy of what you'll see on the proof.

[M. R. Horton]

Thanks for the reply, can I ask what inkjet printer your using.
When you say dot structure, I assume you refer to the screened dot structure (ie 150lpi or 200 lpi), and not the resolution of the output device (ie 1270 or 2540 ... as an example).

When I say dot structure, I am talking about the dots that make up the screens on the printing plates, so that could be AM (traditional half-tone 150, 200lpi) or FM (stochastic) screens.
The inkjet proofs are for in-house press operator use, but the important thing for being able to check trapping is whether the printer driver is outputting AM or FM screens to match the plates, and ours is not. Our soft proofs are rendered using the same AM and FM screens as the plates.

[pdan]

For small press work, InDesign has never failed me with Application Built In Trapping.
Note that ID will not trap anything in an eps, save them as AI, or put the whole piece to PDF first, place that, output DTP.
For tests, if rather than printing direct to the platemaker/imagesetter, Save to PS file instead. Distill that .ps file, zoom way in, and you will see the spreads/chokes on screen; this .ps file can be dropped into your iamgesetter que btw, assuming margins and page size are correct.
And, any pdf printed or distilled to pdf, with Application Built In seps will note such in Acrobat> Properties, on the Advanced Tab.

[APS]

Hi,
I am looking to create Press Ready PDF's with trapping.
We used to produce punched film separations, and a Cromalin Proof. With an eye glass you could see the trapping and check it.

Firstly can you rely on Adobe CS Auto trapping (I believe InDesign can do this) or should you do it manually.

Second, before going to plate (CTP), what is the best method for checking trapping - a soft proof on screen, or with an inkjet (I'm assuming an Epson has the resolution - please advise).

If you can access the 1-Bit ripped data there are some good solutions available to view Screening and Trapping prior to film or plate output.

[eskopdl]

This Viewer tool for Illustrator would allow you to view your traps while you are in Illustrator, check before ripping.
With the registration view you can put in your press tolerance and the Viewer will shift the colour plates to that degree, letting you preview whether or not you may need additional trap in any given area. You can also view by separation, check for overprints and knockouts, view separations as colour, grayscale, or negative, check for areas that may exceed your desired amount of ink coverage, and preview the effects on press due to dot gain.
This is all done in Ai before ripping, and while you can still adjust any areas of concern. As for trapping in Ai, EskoArtwork has tools for that, as well as tools for viewing ripped screened files.
Here's the Viewer - Esko Store: choose your country Download the free trial version.

[michaelejahn]

We ( Compose Systems ) offer two solutions to enable you to review the output of your RIP. If you happen to have a method to generate a trapped PDF file, then but all means, use the free Adobe Acrobat Reader application with overprints on to see if your traps are as required. If you need to turn certain channels on or off, you will need to spend money and buy a copy of Adobe Acrobat Professional, as this offers tools to do that (In Adobe Acrobat Professional, under the Advanced menue item, select Print Production and then cascade select Output Preview...)

Now, if you want to view the post RIP version - we offer Compose Visual Proof;

goo.gl/sNDlu

and if you need to see your dots (not some re-screened dots, but the actual dots you will be using to plate with) - then we offer Star Proof;

goo.gl/Ryoka

Hope this helps. email me at michael@composeusa.com for questions and quotes.