Thursday, 21 August 2014

Peeping Inside the Process

SEAN MICHAEL ROBINSON:

Hey everybody,

This week I've been doing a bit of negative-peeping.

Actually, a lot of negative peeping. In fact, it's more like a negative cabaret.




So, waaaayyyy back in the pre-computer age, offset printing involved photographing artwork with specialized high-contrast film that was then used to create printing plates. When I talk about negatives for the Cerebus material, it's this intermediate stage I'm referring to-- large, at-print-sized negatives, emulsion on a clear carrier, that is the reverse of the printed image.

As I mentioned earlier in the week, I'm not speaking from direct experience here. I've never handled these negatives myself. So far, all the material I've been working with, with the exception of printed material scanned by Mara from Dave's file copies, has been supplied to me.

So as I've been working with the material, I was surprised to discover that there's a lot more hiding out in there than I thought.

Although the negatives are high-contrast, under extreme adjustment there's still significant amounts of continuous tone image hiding inside. In other words, not just black and white information, but gray-scale information as well.

What does this mean on a practical level?

For one, it's possible to radically adjust the exposure of the page. How do you know if a page is too dark if you haven't seen the original artwork? Well, Cerebus's tone is the one constant, and since he appears on nearly every page, I can use his 30 percent dot-tone to eyeball the page back into the tonal range it started at on Dave's drawing board. (This process is aided significantly by the softness of flatbed scanning. Edge information is represented by ambiguous, "soft" gray pixels, which shrink/retreat when we lighten the image, thus thickening or thinning each as you change the exposure).

But most significantly, it means that there's extra information that can "correct" problems in the original printings.

Here's an example from issue 26, the first issue of what would become High Society. This first one is the negative scan. It looks about the same as my printed copy.

The second has been exposure-adjusted, using Cerebus's dot-tone to judge the density. Then I've goosed the area with the broken-up white lines to bring out the surprise--Dave's beautiful fancy-pants coat texture, hiding within. Not only does the image have a much more pleasing balance on the whole, whole sections hiding within the negative have been brought out.

Before this week, I had no idea this was possible. I had assumed, incorrectly, it seems, that the negative film itself was much more high-contrast, more like the printed material it was used to generate, which is, of course, the ultimate high-contrast, either black ink or paper.


Here's another example of using extreme contrast adjustment to work with damaged material. In this case, not only is the page under-exposed, causing the tone to clog up, but the negative has picked up either dirt or pencil left under the tone, causing the figure to look terrible. (It's the bottom of page 11 in the collected High Society). Fortunately, the pencil, or whatever it is, is just slightly grayer than the tone in the negative, meaning that I can eliminate it with an extreme adjustment.

And so the process of discovery continues! (By the way, I'm always on the lookout for an expert--if anyone has any experience working with or even making offset plate negatives, I'd love to pick your brain about a few things!)

7 comments:

Tony Dunlop said...

Well, I'll be…all these years, I'm pretty sure I never knew the inside of Mr. Carron's jacket was plaid.

David Birdsong said...

I am pressed.

Eddie said...

I wonder if anyone even KNOWS this is possible to do with the negatives.

Travis Pelkie said...

Cool.

The only thing I'd say with the dude with the coat is that bringing out the coat's pattern also makes that white schmutz near his mouth more prominent. Other than that, this is pretty cool stuff.

Cerebus Restoration said...

Hey Eddie-

I think if people knew, they'd be a lot less likely to destroy their negatives :)

Travis,

Yup! These extreme manipulations bring out information on the surface of the negative--scratches, tape, corner damage where they were held in place with the other negatives that made up their plate. It's usually an easy fix, though, and there's usually very little of it on the surface of the negative--mostly it's contained to the corners.

In this case I didn't fix this until I confirmed with Dave that it wasn't actually part of the artwork. The light of the soon-to-be-gold-plated streetlights glinting off of his perfect teeth?? :)

Tony again said...

I'm pretty sure Iest at that time couldn't afford even tin-plated streetlamps… :-D

Steve said...

Hi Sean -

I ran small one and two-color printing presses for 15+ years and spent some time stripping negatives and burning plates, but it was years ago and I'm not sure I'd have anything to offer by way of help at the level you're looking for.

I can say that the emulsion sides scratch very easily, hence the 'scar' on Mr. Carron's jaw.

I've seen several Prinney (sp?) printed books where I could tell they were using a two-color press, and maybe even a one-color initially. It's quite tricky to keep quality color registration for four-color; the paper can swell, sheets miss-feed, and the image looks all wacky.

Anyway, if nothing else this brings back some pressroom memories for me -

Steve