Mixing My Own Chemistry

[tgtaylor]

I keep a few old yogurt cups for weighing chemicals. The plastic is inert and is easily washed for re-use. The only exception is when I weigh out Catechol for mixing Pyrocat - that cup retains the chemical’s odor so goes into the recycle bin.

I use little plastic salsa cups https://www.webstaurantstore.com/cho...ck/999P2C.html that I got from a local El Pollo Loco for measuring out small mass of chemistry. For larger mass I use the measuring tub that came with my Ohaus digital scale. The salsa cups are tough and rinse easily. I've been using the 10 or so that I have for about 15 years now.

[LabRat]

Thanks for all the comments and advice. I'll look into ArtCraft. Technical Grade/Photo Grade both sound good too me. We have our local American Scientific that I can check. Definitely do have an automatic stirer.

Interesting on mixing order. I was thinking of making my own bags to be used later??? Maybe better to compound developer only as needed.

Also have a hepafilter grade, full facemask that I always use when mixing powdered chemistry.

Reassuring on D72. Will give it a try. Will be interesting to compare it with Steve's Dektol like recipe.

Again, thanks on all the replies.

With mixing order, mainly that the metol will not dissolve with large quantities of sodium sulfite present, so that is dissolved first (with a pinch of sulfite to prevent oxidation)... Easy enough to follow the "recipe"...

The difference with Dektol vs D72 is Dektol contains a sequestering agent (probably EDTA) that holds all ingredients in separate suspension during the mixing process until they are dissolved...

Pre measuring amounts of dry chem for future use does not allow for the correct stirring sequence, where some chems will not mix completely or fall out of solution... But you can mix a larger amount of liquid stock solutions and bottle it until when needed... But no big deal to mix needed solutions a day or few before darkroom sessions... It is cheap and easy, and satisfying to play mad scientist when you do... But most solutions have a longer shelf life when mixed and stored properly than the commercial products...

Here is that published Agfa 100 formula (similar to the old Neural commercial formula);

Water. 1ltr

Metol 1gm

Sodium Sulfite. 13gm

Hydroquinone. 3gm

Sodium Carbonate (Mono) 30gm

Potassium Bromide. 1gm

Use full strength for 1-2 minutes...

Have fun!!!

Steve K

[Edward Pierce]

Ohaus digital scale and plastic Dixie cups make weighing quick and accurate. Mixing your own is less expensive and more dependable. Artcraft is great and they have everything I need except Glycin, which I get from the Formulary.

Mixing your own can also be very useful. For example, with my VC enlarger (Zone VI), I can’t produce a print softer than grade 3 on Ilford Cooltone or Classic in a standard developer like Dektol or D72. So I have formulated a developer which is essentially 50% Ansco 130 and %50 Ansco 120. This brings these papers into the middle of my enlarger’s contrast range.

I used D23 with TXP and TMX for a while, but found that it didn’t work so well if I needed a big contrast boost, say N+2. The developing times were excessively long. D76H works great.

[jnantz]

im a fan of the table /teaspoon caffenol recipe, works as well if not better than the scaled versions, there's a teaspoon / tablespoon recipe that someone worked out for dektol ( https://www.afterness.com/kod_d72.html ), I haven't tried it yet but it is supposed to work great you just need to be consistent in the size of your spoons and if it ends up as ansco/agfa 124 instead of D72 . it ends up being 6 of one a dozen of the other .. that said I have a amazon purchased scale (under 15 dollars shipped ) I use to make emulsions and cyanotypes, inexpensive and seems to work great too.
have fun with your mixology !

[neil poulsen]

Based on comments, I will adhere to proper mixing order, versus attempting to prepackage the dry powders. So, I appreciate members comments in that regards.

[neil poulsen]

I second Paul's recommendation of ArtCraft Chemicals...reasonable prices and great service. If you decide to buy a scale, I'd recommend reviewing the recipes you plan to mix to ensure that you won't max out the upper weight limit of the scale. For example, I have two electronic scales--one that goes up to only 100g, while the other goes up to 1Kg. I can't mix fixer, for instance, using the "lightweight" scale.

I have a triple beam balance for larger quantities. But, I'd like something less time consuming for sub-100g quantities. Someone mentioned Ohaus, so that's a good place to start.

[Jim Andrada]

I use little plastic salsa cups https://www.webstaurantstore.com/cho...ck/999P2C.html that I got from a local El Pollo Loco for measuring out small mass of chemistry. For larger mass I use the measuring tub that came with my Ohaus digital scale. The salsa cups are tough and rinse easily. I've been using the 10 or so that I have for about 15 years now.

Lately I use the little plastic cups they use to for your pills when you're in the hospital. Being on 19 meds and having spent 10 months in hospitals recently, I have quite a stack of them.

[Mal Paso]

With mixing order, mainly that the metol will not dissolve with large quantities of sodium sulfite present, so that is dissolved first (with a pinch of sulfite to prevent oxidation)... Easy enough to follow the "recipe"...

Thank You! That explains the brown cast and a solution for it.

I'm back into mixing my own as prepackaged is $10/liter VS $1.91 from scratch. I ordered from B&H and Formulary, will check out Artcraft.

Just Bookmarked Artcraft, their price on Sodium Thiosulfate may have me mixing my own fixer again.