Discussion: IOF Accepts Digital Printing

Elsewhere, Simmo pointed out this.

Its a welcome move. Most of us have been using digital (CMYK) printing for its convenience and cost benefits. So it represents nothing more than head office waking up to what happens on the shop floor.

In the past many of us used a major software supplier's recommendations for the CMYK values to use, or at least to start with. OCAD has recently revised its colour table. Any comment on the differences between the IOF numbers, and the OCAD ones? All this symbol conversion stuff is crowding out actual mapping:-))

The IOF CMYK values seems to be based on a professional printing shop's mapping of Pantone to CMYK. As they write very clearly, this is _NOT_ what you should expect from any given Laser printer!

I printed a copy of the PrintTech test sheet on my HP4700 using the IOF CMYK values, and that was way off compared to the optimized values which I spent a couple of months tuning before I got my certification from the Norwegian MC.

The one thing I would love to get from OCAD would be an easy way to import a color table on top of an existing map, but so that only colors used for official symbol numbers are modified: There are too many maps using totally non-standard color tables and symbol sets, and that makes it impossible to just import new spot color mappings.

OTOH, it only takes a couple of minutes to make a local copy of a map after modifying the CMYK entries for the primary map colors.

I know next to nothing about printing technology, however I see that there are a number of CMYK to Pantone converters available on the internet. How difficult would it be for printer manufacturers to standardize the output for all their products?

As far as I know such CMYK offset printing hasn't much been used at all around here for O maps. Mostly been just laser printers or spot offset.

Suggested blue is simply 100% cyan. For sure that produces sharp lines, but it must look quite different from sport offset blue of old. Maybe the use of this paler cyan is the reason behind making ditch symbols thicker in ISOM2017?

One of my pet peeves with offset printing has been how bad most Spot Pantone Black is!

On pretty much all my offset-printed maps, black houses, cliffs and boulders are a lot less black than normal CMYK blacK from a laser printer.

Does anyone know why?

How difficult would it be for printer manufacturers to standardize the output for all their products?

Probably about as difficult as having all clothing manufacturers standardising their clothing sizes - that goes for shoes too.

For WOC93, our technical lead (Pat Dunlavey) got the respect of the people at the offset print shop when he started the initial discussion with, "First, I want to talk about black".

I think my original concern has been answered. Since I'm not using offset printing, I can evolve my colour table from the (new) OCAD default. Theoretically by reference to the IOF test sheet, but in practice by accumulated week-by-week experience with my trusted print shop. (A slight worry if we have to change print shop, but I suppose we'll just repeat the process via many unimportant events at another.)

Since I'm never going to use offset printing this is just an idle query. But I'm curious about the issue with offset black.

@jjcote: Very glad to hear that Pat was on top of this way back in '93!

I'm suspecting that this could be either a way to save on black offset ink, or maybe it is done in order to reduce the risk of getting black smudges when the maps are stacked on top of each other. I.e. to increase the practical printing speed?

What did the printers say in 1993?

I wasn't in the discussion, I just heard about it. He had insisted on the best press operator - she actually worked at another shop, but could be brought in by special request. When he said he wanted to discuss black ink, I guess she smiled and knew she was talking with someone who knew his stuff.

jjcote: :-)

I remember watching the look on the (offset) printers face when our local mapping specialist pulled out a monocular lens and started examining the print from 2 centimetres. I got the impression they believed most clients did not appreciate the technical skill of their profession and so were happy when a client did appreciate their work. It seems our interest was forgotten. Sadly, we had to give up on them when they sent a requested offset print job to an outsourced Indigo print shop because they believed we were like most clients and wouldn't pick the difference. Ironically, that was the last time we ever considered offset.