Dry Plate and handcoated film

[dwross]

Hi All,

Here's a nudge at those of you who are interested in dry plate photography, but haven't quite yet taken the plunge.

I recently posted the beginnings of a new section on Dry Plate photography on The Light Farm, the site I edit dedicated to all aspects of handcrafted silver gelatin emulsions. This morning I posted a page on coating Melenex subbed film base, a commercial product sold by Photographers' Formulary that lets you get the look of the old dry plate emulsions without having to deal with glass.

Dry plate photography is a really great excuse to keep big cameras in your life! I hope more people give it a try.

http://www.thelightfarm.com/Map/DryPlate/MapTopic.htm
http://www.thelightfarm.com/Map/FilmNegatives/MapTopic.htm

Denise Ross

[RJ-]

Denise,

It's such a thoughtful and meticulous introduction to Dry Plate work that I can't help but stop in amazement at the work and energy you've put in to making this aspect of emulsion work more available ~ thank you for putting the work in the public domain.

From the work shown in the link, what seems striking is the degree of clarity and definition available on the emulsion coated glass negative. On the whole plate HP3 emulsion which I'm running out of, I'm finding likewise, that glass negatives possess a clarity which translates better on contact printing, in addition to obviating the use of anti-newton glass for the negative contact print process.

Although this is unorthodox, I wonder if you have found whether fractionally bevelled glass diminishes emulsion flaws?

Kind regards,

RJ

[dwross]

Hi RJ,

Thank you for the very kind words. It has been a lot of work, but I truly have come to understand the concept 'labor of love'. I love the dense, velvety blacks of thick, silver-rich, fine grain emulsions and I'm not the least bit too sophisticated to admit I'm proud of the whole do-it-yourself accomplishment. There has been so much talk-only about emulsion making going about that it has taken on the mystic of impossibility. Nothing could be further from the truth. People were making emulsions at home before electricity! And interestingly, it seems more women were involved with the process in 1900 than now.

You are spot-on about the beveled /gently rounded edges - at least with the way I coat. Anything that encourages the emulsion to run smoothly over the edge and not catch and tear helps improve the finished quality of a plate. I have found that the advice to 'roughen up' the edges doesn't work as well.

The best to you,
Denise

[RJ-]

Hi Denise,

Thanks for your thoughts ~ it's exhilarating finding this interest in image production which has clarity in its workflow from the raw chemistry to the final product. Your technique is really admirable - it's way more sophisticated than mine so it offers an invaluable resource in a field which isn't well explored.

What strikes me is that the high definition and lush tonality of glass plate negatives is on a par with ultra fine grain film such as Panatomic X, Adox 25, Rollei IR400 and ortho films due to the challenge of flatness on the film plane. The number of extant vintage glass plates seem consistently sharper, however whether this finding is due to more due attention and care from (dry) glass plate photographers compared to the more casual 120 roll format photographer, is hard to tell.

In any case, anti-newton glass negative printing or enlarging probably attenuates the image in non-plate glass printing.

On the practical aspect of bevelling or deburring the glass plates - I found this necessary to avoid accidental injury in the dark. It seemed to make sense, since roughening of the edges only seemed to coalesce the emulsion unevenly like a wealed edge.

I'll have to look more closely at the structure of your coating process: it seems you have a sufficiently generous work space dedicated solely for the coating process to start a cottage industry for glass whole plate negatives.

Kind regards,

RJ

[dwross]

Hi RJ,

There really is something special going on with enlarged dry plates. The prints end up looking much more like contact prints than do prints from enlarged film negatives. I haven't done enough careful comparisons of the same image printed from commercial roll film, commercial sheet film, enlarged dry plate and contact-printed dry plate to have a good feel for where the magic comes from. You're probably right about the flatness combined with not having anything between the emulsion and the paper. The tonality and fine grain of a silver-rich negative probably help, too. Whatever the explanations, for now I'm just enjoying it. I think, though, it is probably more about the nature of the materials than about technique.

About a 'dry plate factory': Believe me, the jokes on that subject fly fast and furious in my house. But, I'm afraid I'm too much of a science geek to muster the discipline to be an entrepreneur. I'm actually hoping someone will want to be the next George Eastman. The right person could probably make a decent living at it.

Denise

[Nathan Potter]

Denise, real nice work and very informative. I'm also sort of passively interested in this work but don't have time to expend right now.

A couple of techie questions however:

Any idea how thick your emulsions are say in mils or micrometers?
What is the viscosity of the coating emulsion, say in poise units, or compared to ordinary fluid materials if poise is unknown?

Any thoughts about spin coating the emulsion using a vacuum hold down for the plate. Of course that would take a bit of sophistication and expense with equipment setup but very high thickness control can be achieved. It seems your coating scheme could be characterized as a meniscus coating technique.

Nate Potter, Boston MA.

[dwross]

Hi Nathan,
Thanks.

The emulsion on a dry plate is thick - 4 to 5 mils. When you peel exposed and processed emulsion off a plate, just that emulsion is about the same thickness as a whole sheet of commercial film. I feel thick emulsion is part to the effect, but much thicker than that and it doesn't always develop evenly. I have good luck with my coating technique and it's cheap and easy. I think I'll leave sophistication and expense to others :)

The melted emulsion at 38C, before coating, looks and feels just like heavy cream.

I hope you get a little time someday to give things a try.

Denise