Mixing My Own Chemistry

[Michael R]

1. Ditch the "cookbooks". Simply mix from Kodak or Ilford published formulae - which cover everything. Keep things simple.

2. Get a decent scale. Nothing fancy required. You don't need any other lab apparatus or equipment.

3. Generally unless you need an exotic compound, everything you get from reputable sources will be "technical grade" which is good enough for photography. Photographers Formulary is ok. I think Artcraft and Bostick are a little better for certain things. Not a big difference.

4. Be safe. Compounds best avoided: Pyrogallol, Catechol, PPD, strong acids/bases

5. General best mixing practices:

i) Use distilled water when mixing developers if possible. It simplifies things.
ii) Heat water to approx. 40C to mix.
iii) Proper formulas list the ingredients in the mixing order. Dissolve them one at a time, completely, in that order.

[tundra]

For various reasons, I'm giving thought to mixing my own chemistry for D76. And, Steve Anchell has a recipe for a "Dektol like" paper developer, so I'm considering that as well.

For those who've already embarked on such a process, is there advice that you would offer? Chemical sources and grades, procedures, equipment, etc?

I'm eager to hear what suggestions that you might have.

Lab apron

Eye protection

N95 masks

Nitrile gloves

Good ventilation

A scale with .01g resolution and a scale that can handle 1000+ grams. It likely will not be the same scale.

Glass beakers in varying sizes

Disposable trays to measure things in

Spatulas to lift the chemistry from the container onto the disposable weighing tray.

A heated magnetic stirring stand

A decent thermometer. It doesn't have to be perfectly accurate. A good digital BBQ thermometer serves me well.

Brown glass bottles in various sizes to hold mixed chems. Get the ones with polycone style caps.

I buy most of my chems from Artcraft here in the US, and some from Amazon, and some from Photographer's Formulary


Most of all be aware of how to mix chemistry, what things to never mix together, and basic lab technique. A refresher in basic lab procedures is always helpful. Most things we mix aren't too terrible if you wear good eye, skin, and breathing protection. A few - anything with Pyro, for example - merit extra care. The primary risk is inhalation of airborne dust, so learn how to scoop, measure, and pour while minimizing chems dust. You can practice with powered sugar.

[Alan9940]

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.

[paulbarden]

Oh, and in case you were not aware of this, Neil - when mixing D-76 from scratch, always add a pinch (maybe 1/8 tsp or thereabouts) of the Sodium sulfite before adding the Metol and Hydroquinone. This scavenges the oxygen from the water and helps prevent premature oxidation of the developer.

Kodak D-76

Water 125F/52C 750 ml
Metol 2 g
Sodium Sulfite (anhydrous) 100 g
Hydroquinone 5 g
Borax (granular) 2 g
Cold water to make 1000 ml
Mixing Instructions: Add chemicals in specified sequence.

[Drew Wiley]

I once used a cordless drill stirrer, replete with 316 grade stainless steel chuck and chemical-grade stainless stirrer. No more. Some things will over-oxidize if excessively agitated; and stirring by hand with an ordinary plastic paddle seems to work just as well, with less splash risk, unless you're making up huge quantities at a time. Large amounts in a 2-.2 or 5-gal paint bucket should be stirred at moderate (not high) RPM through the bung hole of the lid, with the lid in place. If you want to go that route, the specialty paddles can be obtained from places like McMaster and Lab Safety Supply.

[jp]

I've got a magnetic stirrer.. Much simpler/cheaper than a heated magnetic stirrer. Let's do me other things while chemistry dissolves/mixes like cleaning up and getting bottles ready

Some things I mix from chemistry ingredients, other things I buy commercially. It's good to have options in any case.

[LabRat]

Not rocket science, and seem to make better solutions that packaged chems... Good route to take and you won't look back with the ease/keeping/costs and quality you get...

A scale can just be an old Ohaus triple beam balance from a pawn shop for $20-$30 that can weigh between about 3/10's of a gram to about 100 without the auxiliary weight sets, which is good for most 1-2 liter stock amounts... Mixing with a magnetic mixer at medium speeds with mixing bar off-center in a standard 2 liter flat bottomed graduate works well with a minimum vortex of air whipped into solution... The mixer works so well that even hard to dissolve agents (like phenidone) mix well at room temperature within a few minutes (in my case)... Heating not always necessary as single components tend to mix better than packaged formulas... A good measure to hold chems on scale is a package of paper drinking cups, as they are remarkably consistent in tare weight, and easy to shake chems in/out of...

Normal safety procedures should be applied, but the usual normal photo ingredients are also in many household cleaning products (at lower concentrations), so no more toxic than housework... Some chems can dust into the air, but many are just crystals that spread like salt... Some can be an irritant to skin if handled directly, but some workers can have allergic reactions to some...

I tried many dozens of formulas from old books etc and have gotten unique results, but eventually searched for "standard" formulas to use for most all my work, and found developers I now use about 100% of the time... For FB papers, the old Agfa 100 neutral tone developer expands midtones and shadows of cold tone papers, gives WT papers a bit more edge, and use smaller amounts of ingredients (economical to mix), and keeps well!!! Film is another success story... Was planning to jump up to 11X14 shooting, but started chem experiments while waiting... Was shooting 35mm film snips to test formulas... To my shock, those tiny negs looked better and better... So forgot about the ULF, got a Focomat, mixed chems, grabbed a 35mm, and went (literally) to town!!! I showed some portrait prints to a sour old pro I worked for, and he asked me if these were shot with a 4X5 or 8X10 camera, and I told him 35mm Nikon... He went ashen... :0

Ask questions...

Good luck!!!

Steve K

[neil poulsen]

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.

[Steve Goldstein]

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.

[Pete Oakley]

I mix D-76H. It's easy relatively cheap and it's never let me down. Water stop bath and a neutral or alkali fixer. I use Foma films and I've found through experience that it's best to stay away from acidic chemicals. I wash the negs then do a final rinse in de-ionised water and just hang them up to dry. Works for me.
Pete.