PDF export in Vector mode does not allow Overprint simulation

[valdisj]

Steps to reproduce

1. Export -> PDF -> Mode: Vector.
2. Select Color mode: CMYK
3. Cannot select "Simulate Overprint" box

It should be possible to export Vector PDFs with simulated overprint. Otherwise maps do lack legibility of contours, when printed from PDF.

All Mapper versions.

[dg0yt]

Overprinting simulation in Mapper is entirely implemented in raster mode. It would probably require significant additions on the third-party PDF component to make it output valid PDFs with a vector overprinting feature. And it wouldn't necessarily mean that it would be possible in the PDF format version expected by the print shop.

The IOF MC decided to deprecate spot color printing. IMO this implies deprecating overprinting.

[valdisj]

Hai Kai,

Just recently IOF mapping commission was sending out test files to multiple printing companies to certify, if the quality of their work is sufficient for major IOF events. Only 3 companies have so far been certified. We are working with one of them (“Siguldas Dizains” in Latvia) for map printing for our events. We prepare PDFs and send to them, so there are no changes during printing process. They are printing on advanced laser printer (not offset). But what is interesting, that the official, original IOF test file (*.OCD) does have SPOT colours defined, and the only way how to achieve IOF certified printout on these laser machines was to use overprinting simulation. Even more - in none of the official docs IOF MC does not tell otherwise.

So, current only workaround we have, is that we are saving from MAPPER as OCD, and then opening these OCD files in OCAD Viewer and there generating PDFs. This way we are able to get vectorised PDFs with color overprint simulation. If OCAD can export that, and they are also using 3rd party PDF components for PDF creation for vector PDFs, there should be a possibility in MAPPER to do the same for vector PDFs.

IOF MC is speaking about depreciating SPOT printing, but they actual work are not following their words in this area. Which means - overprinting is not officially depreciated. Even more - in their Color documents they even suggest that offset printing is still a suggested printing method for major events (IOF_Map_Specifications_Printing_And_Colour_Definitions_A4_2021.pdf). https://orienteering.sport/iof/mapping/

I believe, if we want to position Mapper as fair alternative for all events, incl major events, for maps preparation and printing, we shall look into vector PDFs overprinting simulation.

Valdis

On 2 Jun 2021, at 23:17, Kai Pastor @.***> wrote:

Overprinting simulation in Mapper is entirely implemented in raster mode. It would probably require significant additions on the third-party PDF component to make it output valid PDFs with a vector overprinting feature. And it wouldn't necessarily mean that it would be possible in the PDF format version expected by the print shop.

The IOF MC decided to deprecate spot color printing. IMO this implies deprecating overprinting.

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/OpenOrienteering/mapper/issues/1965#issuecomment-853354845, or unsubscribe https://github.com/notifications/unsubscribe-auth/ABHRZJUM3GB5WHXMI3YXDBLTQ2GWZANCNFSM457LQXBA.

[dg0yt]

From "IOF_Map_Specifications_Printing_And_Colour_Definitions_A4_2021.pdf":

p. 3: "the IOF recommends CMYK printing technology". p. 3, PMS disadvantages: "PMS printing causes overprinting effects, which reduces the sharpness of the print." p. 5-6, colour order: There is no definition of knockout or overprinting. In the whole document, there is no other reference to overprinting, apart from course overprint. The well known illustration, which is the base for our overprinting example, is no longer used.

I think, overprinting couldn't be deprecated more clearly. On the positive side, colour definitions are no longer OCAD screenshots.

(Personally, I don't agree at all with that direction, and how these changes were (not) discussed in advance.)

[valdisj]

Since we, being Mapper community, are very much pro-standartization and strong fit with specifications our our tools and works, should we ask an official opinion from IOF MC in form of a letter to them about overprinting, knock-out, and usage of that for laser printers? Otherwise the doc they have presented lacks this detail and only way to get correct colour representation is on offset layered printing technique, if overprinting simulation is ignored.

Anyone from IOF MC here? Other opinions?

On 3 Jun 2021, at 11:41, Kai Pastor @.***> wrote:

From "IOF_Map_Specifications_Printing_And_Colour_Definitions_A4_2021.pdf":

p. 3: "the IOF recommends CMYK printing technology". p. 3, PMS disadvantages: "PMS printing causes overprinting effects, which reduces the sharpness of the print." p. 5-6, colour order: There is no definition of knockout or overprinting. In the whole document, there is no other reference to overprinting, apart from course overprint. The well known illustration, which is the base for our overprinting example, is no longer used.

I think, overprinting couldn't be deprecated more clearly. On the positive side, colour definitions are no longer OCAD screenshots.

(Personally, I don't agree at all with that direction, and how these changes were (not) discussed in advance.)

— You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub https://github.com/OpenOrienteering/mapper/issues/1965#issuecomment-853696612, or unsubscribe https://github.com/notifications/unsubscribe-auth/ABHRZJWUMNIPJ7FDFLLPQU3TQ453NANCNFSM457LQXBA.

[dg0yt]

@krticka ?