Large Format Photomicrography part: IX

At this point we have a few negatives, not to say that any of them are up to snuff, only that they are negatives. If one was of a mind to display one on a small light box permanently that would be the end of it, but a photographic print is much easier to display, and anyway that was the goal. The process of making a positive print from a negative is rather similar to that of producing and developing the negative to begin with, so some of this should feel a bit familiar.

Background

The positive print is made by exposure of a sensitized paper to light which has been moderated by the negative placed between the light source and the photosensitive material. Which is to say emulsion on the paper operates chemically in the same way as that on film. Areas which are exposed to more light are darker while areas that are exposed to dimmer light by virtue of it passing through a darker area of the negative are lighter—it’s essentially a negative of a negative—we call a positive. This means that if one were to load a sheet of light sensitized paper into a film holder in place of a sheet of film one would obtain as a result a paper negative. There are specialty papers (and exotic processes that can be used with standard papers) that will produce a direct positive and so can be used to obtain a positive print directly without a negative (or a paper negative from a negative). Without using direct positive paper it’s necessary to use instead a negative.

The arrangement will be as follows: light source, negative, and then sensitized paper. The emulsion sides of both negative and paper will be facing each other. If there is an appreciable distance between the negative and the paper the resulting print will be an enlargement, if there is not the resulting print will be identical in size to the negative. In the aforementioned instance (of an identical sized negative and print) the result is called a contact print.

Chemistry

Much like the negative, the exposed print may be processed in trays or daylight processing containers. It will require a developer, a stop bath, and a fixative. Once again a plain water stop bath is enough for the middle step. The same fixative can be used, but it’s important to note that when prepared for use with paper most fixatives will be more dilute than when prepared for film. In the case of Kodafix, rather than the 1:3 dilution used for film, a dilution of 1:7 will be used. It is not recommended to use fixative that has been previously used with film for fixing paper or vice versa. The developer used for paper is slightly different in formulation than that used for film. The reason is owing to the significant differences in the emulsion on paper as compared to that on film. Although some developers are suitable for both film and paper there is little reason to avoid using a different developer as one will be obliged to prepare the working solutions differently and store them separately anyway.

The Kodak D76 used for film can be used to develop paper. It has little to recommend it for the task and in favor of using something with explicit documentation the Kodak standard for black & white paper, Dektol, will be used instead.

Paper

The paper used is called photographic enlarging paper, or sometimes simply photographic paper. In this modern day and age searching for photo printing paper is apt to present the searcher with only page after page of papers meant to be used with various computer printers that are specialized for printing digital photos. Apart from enlarging paper there exists a second type of sensitized paper called contact printing paper or simply contact paper. Contact paper is made specifically for that use and is exceptionally slow when compared to enlarging paper. Slow in this case means that one needs either brighter light or longer time to expose contact paper.

There are a number of further variations on paper, a few of the more commonly seen are as follows:

  • Contrast, may be graded 1, 2, 3, etc. or VC for variable contrast (multigrade)
  • Material, resin coated (RC) or fiber based (FB) most paper is RC
  • Finish, matte or glossy

Printing Method

Contact printer on the left, portable 35mm enlarger on the right.

The usual method of producing a contact print makes use of the material one is expected to have on hand in the darkroom, that is a printing frame or easel and a photographic enlarger. The enlarger is not strictly necessary, when used for contact printing it serves only as an easily controlled light source. At the time of the release of the Kodak Brownie contact prints were made with the light of the (all too seldom seen) sun just up the road in Rochester, NY. Some few years after that, in the days when medium and large format cameras were more common (a classic holiday snapshot camera would shoot postcard sized negatives on a roll of paper-backed film) a hobby photographer who didn’t have an enlarger was sure to have a contact printer.

A contact printer is a small box, roughly the size of a breadbox, containing a light source below a frosted or opal glass plate. Above the glass, where the negative is placed emulsion side up, one is most often going to find either one or two pairs of movable blades that may be positioned both to hold the negative and frame its borders. Above that is some form of hinged plate, often fronted by felt or velveteen. When pressed down firmly this levered plate activates an automatic switch. The switch will at a minimum turn on the internal light source though it most commercial produced models it will switch off an internal safelight as well. Contact printers are seldom used in the present day, not only because of the waining popular interest in large format photography but also because they are unsuitable for use with enlarging paper. With a contact printer of the type described one must use contact printing paper and an exceedingly low luminosity light source. Originally intended for use with silver chloride contact printing paper, modern contact papers are much faster, and should not be treated in the same way.

Proposal

Considering the above, one might be forgiven for thinking there is no way to make a contact print without a darkroom. I propose to cram the following into my large changing bag: a box of modern contact printing paper, a contact printer loaded with a negative and outfitted with two 15 watt night light bulbs, a daylight print processor. It’s going to be awkward and cramped to say the least. Inside the closed changing bag I’ll need to remove a sheet of paper from the package (and reseal the pack). Expose the paper with the contact printer. Place the exposed paper into the daylight print tube and close it up. If I can manage all that then I can take the print tube out and process the print.

As may bee seen in the two photos above there is not exactly ample space in the changing bag. It would be comparatively easy to wait for nightfall and work in my spacious basement with the lights out and the windows curtained, even working in the broom closest would be far more spacious. Still, I’ll give it a shot just to see before I cave in and use the improvised darkroom curtains I hung around my utility sink.

Next time, prints! -K

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