Ammonia in Emulsion Making

[jsmithphoto1]

Hi, everyone! I am just about to start the most awesome and most amazing journeyof my life by mixing my own emulsion from scratch in the near future. But, there is a setback that I am facing. I have seen PE's posts about using ammonium hydroxide and photoflo in helping in digestion as well as coating... I am making glass plates btw. I feel as though I have become the irrelevant, yet annoying, coupons in PE's e-mail with my questions, which is the reason for this post lol. My question is (for him as well as anyone else) would it be possible to use household ammonia in emulsion making to get the best of both worlds? I understand photograde this-n-that, and it more than likely is NOT a good way to go, but entertain me, here. The possibility... is it there? If so, is it valid? Thanks so much in advance!

 

[dwross]

Short answer: no.
...and a question. Why would you want to?

This isn't in any way meant to be dismissive or snarky. Making an emulsion is drop-dead simple with only a few good ingredients required. I often wonder if there is something I'm missing. The real goal doesn't seem like it's being able to do dry plate photography, but rather "I can make Kodachrome in my bathtub with stuff I found under the sink." Or, on the opposite end, playing with really cool, complicated machinery.

A lot of other philosophical questions get posed on APUG. I know this one has a limited audience, but I would truly like to hear a few opinions.
d

 

[Photo Engineer]

Ammonia in emulsions is used to get larger and more uniform grains. Usually, with my formulas, you get rounded cubes as shown in the micrographs in the book.

However, you have to use concentrated Ammonia which is about 25% - 28% Ammonia in water. Household Ammonia is about 2% - 3% which ends up resulting in a very very dilute emulsion.

The Formulary and other chemical suppliers sell this concentrated form.

Emulsion making can run the gamut of no Ammonia to Ammonia hand makes or machine makes and with fancy or plain wash methods. It does not matter. What works for you is what matters. And I answer all e-mails and PMs. There is no bad question.

PE

 

[jsmithphoto1]

It was just curiosity getting to me, honestly. I see what youre saying. My thought process was that of "is it pure enough and would it work?" Seriously nothing more than mere curiosity .

 

[jsmithphoto1]

Thanks so much for your information! I see... So, here is another question: could one use a small amount of final rinse from an SM unit in lieu of PhotoFlo? Or is it really THAT important to use a surfactant? I could see the coating being thinner than without? Thanks for your response to my e-mails! I just dont want to be the person to bombard your inbox, which I could easily do

 

[Photo Engineer]

I don't want to open that can of worms, but I guess I have to. The new Kodak final rinse is both a surfactant (Photo Flo 200) and a bacteriostat (such as the thymol that I recommend). However, this bacteriostat is as much as 1000 x stronger than Thymol and I have not tried it. It is hard to get due to EPA rules and it is stabilized with several metal salts. I have not tried it but have been told that it can work.

If you use it, it is on your own shoulders. Sorry.

BTW, the "pure" stuff (10% in solvent) comes in sealed glass ampoules with instructions on how to open them with glass cutting files. So if the Final Rinse works, it will be great. However, in the meantime, I have another bacteriostat that is much safer and is about 50X stronger than Thymol. So, have patience, one or the other is going to be out there someday if we are lucky.

Why worry so far ahead, you don't seem to have made the emulsion yet?

PE

 

[jsmithphoto1]

Very interesting can of worms! A safer bacteriostat? Very nice! Correct, it is not made, yet! Hmmm... what I may go ahead and do is set aside a small amount of emulsion and add some final rinse to it to see what happens. If it goes awry, that's just a few milliliters of emulsion instead of a whole batch. Just getting everything aligned and gathering as much information as possible before going at it. I have all I need, minus thymol and ammonia. I can't wait to get it made, though! This is way beyond my childhood dreams!

 

[Photo Engineer]

I suggest then, 1 ml / 100 ml of emulsion to start.

A WAG!

PE

 

[jsmithphoto1]

Thank you for the recommendation! BTW... I was re-reading my last reply and noticed it read as though I were gathering info on adding the final rinse in the emulsion. On the contrary, the info I was talking about was correctly making this emulsion. My apologies if it seemed as though otherwise.

 

[dwross]

It was just curiosity getting to me, honestly. I see what youre saying. My thought process was that of "is it pure enough and would it work?" Seriously nothing more than mere curiosity .

Me, too.

You may have your heart set on an emulsion with ammonia but perhaps you might start easier with an emulsion made without ammonia. And, if you are planning on coating your emulsion when you make it, you don't need a preservative.

Here are a couple of "PE-approved" links:

http://thelightfarm.com/Map/DryPlate/Osterman/DryPlatePart4.htm
http://www.thelightfarm.com/Map/Books/Osterman/MapTopic.htm

 

[jsmithphoto1]

Very cool and good to know about the preservative! Thank you! I would love to do an ammonia-based emulsion, but i have spent enough on shipping already to make twice as much emulsion haha. I have a formula to make approximately 50 plates, but only have almost 30 cut, and plan on coating what I can. What's left is going in the fridge in a black bottle i got from the Formulary. Maybe that will bar the need for preservative? Thanks so much for the information and links!

Also, here is another question, totally irrelevant, though...

Back in, ohhh, 2009ish, Ferric Ammonium EDTA was readily available. What happened to it?

 

[Photo Engineer]

Ammonium Ferric EDTA is still available. It can be purchased as a solution from many photo suppliers and is a part of the RA4 bleach fix.

I'm not sure what you meant by addition of Final Rinse then. It would be of little use or none when making an emulsion. It might help in storage of the emulsion (like Thymol) or in coating (like Photo Flo), but would probably do nothing more.

As for the references that Denise gave above, the MO1880 is generally taught as his plate emulsion, ISO 1 - 2 and is blue sensitive. The results are very nice. There are several variants out there, but in the end they are all similar. Plan on using about 12 - 15 ml / 4x5 plate.

As for gelatin types, we usually use Photograde 250 Bloom gelatin. This is a "stiff" or "hard" gelatin, but terminology has changed. What Mark and Denise think of as a Hard gelatin is one with a high Bloom Index, but back in the first 50 years or so of emulsion making in gelatin, Hard gelatin was one with lots of Sulfur containing amino acids and one which ripened the emulsion rapidly. To add to the confusion, these were called Hard Blooming, but in German, Blumen meant ripening in the photo circles back then.

So be careful about Bloom, Hard, Soft and etc. Make sure that you get 250 BI or 250 Bloom Photograde, inert oxidized gelatin. There are many many other types, but this designation will not mislead you. Even so, across companies the result may vary.

PE

 

[jsmithphoto1]

Oh. I may not have been searching correctly for it, then. Oh well.

That is what I meant by the addition, to help in coating.

From what I've read, my hopes weren't going past ISO 5 haha.

I purchased the plain 250 gelatin from the Formulary. What is the difference in the plain versus the phthalated? Wow that is some very nice and very interesting information! So, they basically graded the gelatin back in the day as we do water now (hard, soft, etc)? Interesting!

Thanks so much for the info!

 

[Photo Engineer]

Well, the Formulary is selling genuine Kodak gelatin and is very inert. The Phthalated gelatin is made in such a way that washing out the salts is facilitated by an acid / base pH cycle. It is beyond the scope of this forum, but is explained fully in both my book and the DVDs with lots of visual info. It is an advanced technique that you could move on to at a later time after you master noodle washing.

PS.... One of our fine research emulsion makers was Jim Smith! It is such an uncommon name, I thought you might be interested.

PE

 

[jsmithphoto1]

I will have to purchase your book and dvds soon I can tell! Genuine Kodak gelatin, huh? That is good to know! It would be very interesting to work with phthalated in the future, as you said!

Yes, that is interesting!

 

[jsmithphoto1]

I guess one final question. I've read conflicting info on this... Is it okay to use the plates, say, a month after I pour them so long as they are refrigerated? The contradiction I have read is that you lose speed about a week later, and another source said speed is gained. I'm sure this is no problem as long as they stay cold?

 

[dwross]

No need to refrigerate dry plates. Keep them dry at cool'ish room temperature (and dark, of course).

I don't know what emulsion you're using (a commercial "Liquid" type, I assume) but if you melt it at the recommended time and temperature, the speed shouldn't change for a long time under good storage conditions.

If you are making your own, the speed will increase a bit if you didn't give it enough time for the final heating, and it will lose speed if you gave it too much. It would also likely be a little fogged, so it's easy to tell if you overcooked it. But an emulsion made without ammonia is pretty hard to ruin. Another advantage to a slow emulsion is that it is forgiving of exact exposure times. In other words, the exact "speed" doesn't matter as much as with fast emulsions.

 

[Photo Engineer]

It depends on emulsion, treatment such as washing, gelatin, and a whole list of other factors. I cannot give a specific as I have not run tests exactly like you suggest. I have seen both speed losses and gains within a week or 2 made by 2 people in the same lab. OTOH, I have seen a similar emulsion be unchanged over 1 year when coated on paper.

You will have to run tests. That is not hard.

PE

 

[jsmithphoto1]

Great info you two! Thanks so much!