Saturday, 23 August 2014

Technical stuff

Every now and then I'd like to know a bit more about how all those engraved stamps have been produced. Especially when the printing process just baffles me, as it does quite often. It's simple enough when looking at the classic monochrome recess-printed stamps, but how to explain away a stamp like this?


Well, luckily enough this particular stamp, engraved by Claude Durrens, has been part of a souvenir sheet produced for the French Postal Museum. The sheet shows the various stages of the printing process.


Basically, if I understand it correctly (which is always slightly doubtful, seeing that I'm quite technically challenged), the first bit (impression taille-douce report) is printed by engraving three different colour cylinders, which together form the complete background. I believe this is called indirect recess, because the cylinders may be engraved, but the resulting print is not in actual recess, i.e. one cannot feel the lines of ink lay on top of the paper. I presume that's because the engraving is more in colour swathes rather than delicate lines, and the three colour cylinders together form a complete printing of the whole surface.

I'm just wondering who engraves these cylinders? Would that be the same engraver who engraves the actual design or would this be an 'in-house' engraver specialising in this kind of work?

Anyways, the second phase is the printing of the design engraving, which is proper recess-printed stuff. The sheetlet shows this part as a separate printing, which is fantastic, because purists think this is the only real recess-printed stamp, with other stuff just being modern distractions. Although I'm not that much of a purist, I do see where they are coming from, and I wouldn't mind, nay, would even applaud, a return to the old-fashioned recess-printed stamps only. By printing the design engraving on its own one can enjoy the actual art so mnuch better, I think.

So, I think I now more or less understand this process, but what about stamps where the actual engraved design is printed in several colours, such as this one, engraved by Claude Jumelet?


Again in the old days, bicoloured recess-printed stamps required two engravings (usually one of the frame and one of the vignette), which were printed one after the other, and which regularly resulted in shifts of either print. But it seems to me that these more modern stamps do not require several printing plates but that the modern presses can print several colours in one go? After all, this same stamp also exists with an 80k value, and not only have the colours been changed around a bit, the division of the design has also changed. What I mean is that e.g. the postbox on the 70k values has the colour of the boy whereas on the 80k value it has a separate colour.


So I don't presume that for these stamps four differnt engraved plates have been produced, but I could be wrong of course. Anyway, it all seems truly remarkable and unbelievable, and I have no idea how they manage this sort of printing, so if anyone could enlighten me in 'dummie speak', I would be eternally grateful!

:-)
Adrian

UPDATE:
I've since learned that indirect means that the image is printed indirectly from the printing plate onto the paper because there's a transfer cylinder in between the two. So there's an extra step which means that the original engraving for this indirect intaglio needs to be in normal image (rather than mirror), and that is also why the die proofs are in mirror image. 

No comments:

Post a Comment