Liquid Emulsion - do it your selfers

Thanks John and mshchem for the elucidation.

:Niranjan.

I don't have personal experience with this, but I understand that the washed emulsion will also stick better to glass, and with paper that's not a problem. When I was playing around with VDB in gelatin on glass, I found that an extremely weak solution of albumen ( 1% ) on the glass first, then dried, made the gelatin stick well. The albumen was crystal clear when it dried, almost impossible to see.

Nodda Duma said:

Right. Liquid Light seemed set up for coating non-glass things where you want it to go on thick and set quickly. It’s also a silver chloride emulsion

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Jason, is this the correct stuff to get for making my own dry plate negs?

https://www.freestylephoto.biz/174052-Fomaspeed-Liquid-Photo-Emulsion-with-Hardener-1-kg

paulbarden said:

Jason, is this the correct stuff to get for making my own dry plate negs?

https://www.freestylephoto.biz/174052-Fomaspeed-Liquid-Photo-Emulsion-with-Hardener-1-kg

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my guess is it’ll be thick but it’s hard to say. I just make my own (which I think when you tested a couple years ago I had a chemical go bad and they were really thin but which has since been corrected).

for coating glass — assuming you do everything else correctly — gelatin percentage should be about 5.5-7%

Does anyone have experience with Rollei Black Magic Variable Contrast Emulsion? It calls for Rollei RPN Developer, but that's near impossible to find. It says to use a "High Energy" developer. What does that mean? What are some suitable replacements? Thanks!

urnem57 said:

It says to use a "High Energy" developer. What does that mean?

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Print developers are generally much higher energy than film developers.
Some of the old graphic arts developers were as well.

urnem57 said:

Does anyone have experience with Rollei Black Magic Variable Contrast Emulsion? It calls for Rollei RPN Developer, but that's near impossible to find. It says to use a "High Energy" developer. What does that mean? What are some suitable replacements? Thanks!

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hi urnem57:
As Matt suggested use a print developer. One way to think about bottled/liquid emulsions is they are basically paper emulsion in a bottle. Some are a little different than others but for the most part they can be used with a safelight and paper developer.
have fun!
John

Thanks. I plan on doing just that. I am intrigued with the possibilities that a VC emulsion offers. Like anything photo related, there’s no one “right way” to do things. I just needed a starting point.

Ok. Making great strides thanks to this forum. I have 4x5 glass plates subbed w/a Rollei Gelatin & chrome alum mixture. That part went pretty well for my first try. One plate has some streaks on it, the others are quite clear. They are dried. I am now going to coat them today. I am using Foma Emulsion for the foreseeable future, as I learn my process. It was on sale at Freestyle recently, so I am going with it. My question is about exposure. I will be shooting them with a Speed Graphic with an Aero Ektar f2.5 lens. What ISO is the ball park to begin with? I also have a blue 47 filter to put over my incident meter for a rough idea of exposures. I realize that testing, testing, testing is the name of the game but I am uncertain as to where to start as far as ISO and exposures go with this new endeavor. Thanks in advance.

Start at ISO 2.

if you meter with the blue 47 filter in front of your sensor, set the meter to ISO 8 (2 stop adjustment acts as a filter factor).

Awesome. This coming straight from the maestro. Thank you!

Well....that was an unmitigated disaster. The emulsion melted down well enough in 35mm film cans, but it was like doing wax-resist painting. When I went to pour the emulsion on the plates, it was practically beading up and not sticking at all. Whether I poured directly from the film can or tried a syringe I could not get any adhesion. I washed the plates with calcium carbonate, a drop of dish soap, and scrubbed them with a cotton pad. I let them dry thoroughly and then subbed them according to these instructions:

Preparation of subbing layer (done under normal lighting). It is essential that an initial subbing layer be attached to the glass, or else the emulsion layer will simply detach during tray development. Although varnish may work too, the traditional gelatin subbing layer is the most
e$ective. In addition, it can be removed with bleach if one wishes to reuse the glass. The following recipe is what I use for a batch of four 4×5′′ plates, though far more plates could be treated with this amount:

A. Heat up 50ml. of distilled water to a maximum of 50 degrees C. (about 125 degrees F.) in a beaker. Then pour 1g. (1/4 teaspoon) of chrome alum into this water and stir with a standard darkroom paddle until dissolved. Without this hardening agent the subbing layer tends to frill and sometimes completely separate from the glass during tray development; so the small expense is worth it.

B. Sprinkle 3.5g. of gelatin onto surface of 236ml. (1 cup) of distilled water. Let this stand for 10-15 minutes so that the gelatin can swell up. Then heat up the mixture until the gelatin is dissolved. Pour contents into a third container that is speci#ed for photographic use only.

C. Add 5ml. (1 teaspoon) of chrome alum hardener solution (from step A) to gelatin solution to make a total of approximately 240ml.

D. Add approx. 15ml. (1 tablespoon) of Photo-Flo to this same mixture to make approx. 255ml. of gelatin/chrome alum/Photo-Flo solution.
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E. While the solution is still warm, pour it over the glass plate and spread evenly by tilting the glass. Because it isn’t always easy to see which surface has gelatin, I go ahead and pour gelatin over both surfaces. Once this is done, carefully lean the glass against a vertical surface to dry. In order to prevent excess gelatin from collecting at the lower end I drain o$ most of the excess and allow the surface to cool somewhat before placing it vertically. Allow the plates to dry for at least 6-8 hours before proceeding with the next phase.

The chrome alum solution (the 45ml. left over) will only keep for about a day, so it should be disposed of. Why the waste? Because I can’t measure a smaller amount accurately. I keep any left over gelatin/chrome alum/Photo-Flo solution in the refrigerator for a day or two in case I wish to make more plates. After three or more days this solution loses it’s beneficial properties and should be disposed of. (Source: The Dry Plate Process. Mark Scholer Peterson. www.alternativephotography.com)

Where am I way off the mark? I can reuse the coated plates by cleaning with bleach, correct?
I stopped after 2 and had 4 more ready to go. I didn’t want to waste more emulsion.
I realize that there’s a learning curve to this and am willing to pay the tuition for the lesson.
I already have a new and better appreciation for how good the guys that had to do it this way were.
Thanks in advance.

Ok. I finally got out and shot 4 plates today. They are still drying or I would post pictures. Naturally, The J Lane plate came out perfect. My hand poured ones? Well not so much for a first try.
One of them had a mess on the non emulsion side - fingerprints and streaks of undeveloped white emulsion that did not clear. If it’s unexposed, does it not develop or fix away? I also screwed up which side was coated and which wasn’t. I have a way to fix that. My other questions are:
1. Does developer (HC110 Dil. B) develop the clear part of the image? Is that why it’s done in a white tray?
2. Does the fix remove anything unexposed? The clear or dark part?
3. Can fixing be done in the light after a bit of time has passed? Say 5 minutes into a 10 minute fix?
4. I was afraid to scratch or damage the good parts of the image by trying to wipe or scrape away the solid white emulsion (unsure which side had emulsion on it) I tried doubling the developing time and doubling the fix time, but it would not clear. Can it be scraped off with a razor once it’s dry?
5. Why are there sections of white emulsion that do not appear to have been exposed or develop away when the rest of the plate has an image. Is it on the opposite side of the emulsion? I can’t feel a difference with my fingers.
Thanks in advance. This is really a kick. I have a new found respect of the earlier photographers who had to pour their own plates. It’s tricky and like everything with LFP, it offers multiple options to screw it all up.
Update: as they are dying, some of the areas that were white have cleared, but they are bubbles that are not adhered to the glass. I’ll put up some scans tomorrow.

I’m only into my first box of plates, so I expect to be fighting the learning curve. I shot some plates last week, outside, middle of the day near the ocean. Held a blue #47 filter over the meter with ISO (I still like ASA better) 100. These plates came out properly exposed. The 2nd outing, I was shooting cars, in the sun, middle of the day, and used the same metering technique, but everything came out very thin. Thin to the point of unusable. The thin ones are drying right now, or I would put up a scan. What is the difference in why I got such thin plates the 2nd outing? Thanks.

mshchem said:

Silver nitrate is super easy to make. But the fumes are a deadly, corrosive nightmare. I've done it at home once, got beautiful needle like crystals, major pain. If you had access to a real laboratory, like I did 30 years ago, it would be easy peezee!

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a) https://illumina-chemie.de/viewtopic.php?p=71147#p71147 (in German)

b) http://www.sciencemadness.org/talk/viewthread.php?tid=82435 (same experiment in English)

bj68