AuthorTopic: [NPA] How dithering was done before pixels were invented  (Read 5077 times)

Offline Manupix

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I collect 1900's postcards. Most are B&W, but some printed in color have an amazing beauty, partly because of a pretty advanced dithering: thought I'd share a few.

Here are 2 examples showing almost 'pixelly' palette management and texture dithering: an Italian view of the famous Capri Grotta azzurra, and a German scene titled 'Glück auf den Weg'.
(to limit file size, these are cropped 600dpi close-ups with thumbnails of the whole cards, looks quite large in the preview already!)
I'll post more if pple are interested.

Any ideas about the printing technique, the name of this dithering and how it was done?






Offline WM

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Re: [NPA] How dithering was done before pixels were invented

Reply #1 on: December 03, 2009, 10:30:02 pm
Well, when refering to paintings (rather than printed works), there was a very famous art movement in the first half of the 20th century called Pointillism, where the artist used dabs instead of strokes and combinations of different amounts for dots and colors to create a realism painting.

If you already know about this then I'm sorry for throwing definitions at you.  :-X

http://en.wikipedia.org/wiki/Pointillism


Chuck Close makes great work of dithering, and his methods are strikingly similar to those of pixel artists:

http://en.wikipedia.org/wiki/File:Chuck_Close_2.jpg

Offline Mathias

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Re: [NPA] How dithering was done before pixels were invented

Reply #2 on: December 04, 2009, 01:04:50 am
Yeah, I just figure it's pointillism too, or a form of, at least. As for the printing technique, I don't see anything remarkable in the printing of these. No halftoning is apparent. I believe they're just straight-up reproductions - the printing method didn't alter the look.

Any questions I have in reference to these are of the technique the artists used making 'em. And not go insane in the process! Must be special brushes used. I'd really like to see a pointillism artist at work. I love the first one's color mixing! Those greens and blues are so interesting. Thanks for sharing.

Offline Dusty

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Re: [NPA] How dithering was done before pixels were invented

Reply #3 on: December 04, 2009, 01:06:43 am
If halftoning is not visually apparent, then doesn't that accomplish the exact thing you want from dithering?

Offline Mathias

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Re: [NPA] How dithering was done before pixels were invented

Reply #4 on: December 04, 2009, 03:26:04 am
what what whawt hwatat

That's an interestingly posed question . . .     Essentially yes. Halftone dots made by a printing press using only cyan, magenta, yellow and black  and  pixels placed in order to facilitate gradation with a limited palette accomplish the same goal by way of the same basic method -BUT-  halftoning is just a computerized formula-governed array of dots printed to paper that indescriminately overlap eachother in order to reproduce the original only as accurately as the available DPI or resolution permits, but dithering is a human process and the results of which are actually part of the artwork, not just a printer's raster image processor (RIP) unit's robotic interpretation, when being produced in the real world, like halftoning is.


geez that's a really crappy answer. Honestly I still can't reckon the irony of your statement, Dusty. Not that there's anything wrong at all with your question . . . but . . . printing, dithering, printing, dithering, halftoning, one's human, one's robotic, both are the same. Yes. No.
« Last Edit: December 07, 2009, 05:20:13 am by Mathias »

Offline Manupix

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Re: [NPA] How dithering was done before pixels were invented

Reply #5 on: December 05, 2009, 01:07:10 am
Thanks for the input guys!

I hadn't thought of pointillism - how silly of me.
However, I have to disagree on the main point: these cards are not pointillist paintings or drawings, reproduced as is.
No halftone reproduction method is visible at all, either mechanical (screen) or chemical (random).
The dithering stems directly from the printing method itself.

By contrast, here are some close-ups at similar resolution (600 dpi) of postcards obviously reproducing paintings (I link to them, so as not to clog the thread with too many big images):
a view of Venice http://files.myfrogbag.com/qe1mq0/Venezia%20notte%20B%20det%20600-6%20tram.jpg and one of Norway http://files.myfrogbag.com/qe1mq0/Nge%20fjord%20CFEN%20det%20600-6%20tram.jpg, both using halftone screens; a view of Egypt http://files.myfrogbag.com/qe1mq0/Memnon%20CPT7364%20det%20600.jpg with random halftoning, which I believe to be a color collotype http://en.wikipedia.org/wiki/Collotype (I'm not positive about it, I'm not even sure color collotypes actually exist; what I know is that this process was widely used for B&W postcards, and has excellent random high res halftoning. Scanning at 600 dpi is not enough to get everything out of the best of these cards. The random texture I see in this one is very reminiscent of that).
All three obviously show the original painting technique and texture: they are reproductions.

I hope the difference with the former images is obvious enough.
This is also why I find those so relevant to pixel art - and posted them here: whoever invented this, was thinking and working in a very similar way to us, and found a great creative way to turn their medium restriction(s) into beauty.


Also silly of me, I actually had the answer all along and didn't think of it: chromolithography http://en.wikipedia.org/wiki/Chromolithography.
Look at the full res first image, The Old Woman Who Lived in A Shoe, which uses exactly the same dithering technique as my postcards. The other examples shown do not, though.
I have a few of these little naive advertising chromos, most of them with the same dithering and similar palettes; see one below.

The process is described in the article: Each color in the image must be separately drawn onto a new stone or plate and applied to the paper one at a time.
What we have here is a direct graphic creation, of something that only exists as art on the final print; and has by nature a limited palette.

This is somewhat different from pointillist painting: the painter uses pointillism by choice, to the extent that he wishes, remains free to mix whatever colors he wants, and gradually builds the actual piece of art.

An interesting question would be: did pointillism influence chromolithographers? Did chromolithography influence pointillism?
The article dates chromolithography from 1837, although the dithering method was probably introduced much later. The Old Woman Who Lived in A Shoe is from 1883, the year Seurat started work on his first pointillist important work, according to French Wikipedia http://fr.wikipedia.org/wiki/Pointillisme (more examples shown than in the English page).
I don't know when those cheap chromos appeared, but when they did they were just everywhere (exactly like postcards not long afterwards). The pointillist artists must have seen them, and were probably as interested in them as we are, for the same good reasons!


I might post more chromos later.



Btw, I couldn't find a way to link a url to the text, without showing it whole. Is it at all possible?
« Last Edit: December 05, 2009, 01:09:40 am by Manupix »