Mixing My Own Chemistry

[neil poulsen]

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.

[xkaes]

There are lots of good balances for very little money. Get one that gets down to a hundred of a gram. No need to get reagent grade chemicals -- use photo grade.

[Tin Can]

Get a good magnetic heated stirrer

bought one years ago

and good beakers

[Graham Patterson]

Weigh onto slick surface paper, not the top pan of the balance. Most balances have a tare function to zero off the paper which saves doing arithmetic during weighing. I have a few proper spatulas for weighing. One with a scoop end for big weights, and a smaller square end one for fine weighing, but you will find what works best for you. Remember to wipe the spatula clean before moving on to the next chemical.

Most chemical 'recipes' presume room temperature water, around 80% of the final volume, and mixing in the order given. Different mixing temperatures may be given. The final volume is made up after mixing (and at room temperature), and ideally you want one of more storage bottles of the correct total volume.

Label bottles correctly (including raw powders), and keep them separate from everything else. Eye protection is a good idea - fine powder in the eyes is a literal pain.

It is all fairly logical.

[Fred L]

fwiw, when I mix up 4 litres of Formulary 130, I use a dedicated bucket and small cordless driver/drill with a paint stirring attachment. Don't need to run the drill at max speed but have never noticed any oxidation issues from over vigorous mixing. First lab I worked in had a large metal pail with a drill attached for mixing huge quantities of D-76. Got buzzed a few times when there was a short or something.

+1 on the recommendation about scales. Small digital scales that have tare function save lots of aggravation. They're also very affordable.

[Eric Woodbury]

Except for very photo specific chemicals, I find many of the basic chemicals at Amazon and eBay.

Instead of Dektol, I prefer Ryuji Suzuki's DS-14. It keeps well and no carcinogens.

[Ironage]

I prefer Photographer’s Formulary. I have been using them for decades. It is a small company and they off great service. If you want formulas there is an App called Formulas in the Apple App Store that has lots of them. Better living through chemistry!


Sent from my iPad using Tapatalk

[paulbarden]

Neil,

If the "Dektol alternative" Anchell describes is D-72, then it's as close to Dektol as you'll ever need it to be. I make and use D-72 and find it perfectly suitable.

I recommend buying the raw materials from Artcraft Chemicals - they have good prices and excellent service. I get all my materials from Artcraft. You can buy a digital scales off Amazon for about $20, and I have had mine for 4 years and it works very well. Just don't drop it, or you'll ruin it. It's very precise.
A heated magnetic stirrer is overkill if all you want is to make a couple liters of D-76 every few weeks. It's just as fast and simple to heat your water and use a suitable stir stick to mix. D-76 can be assembled in 5 minutes.

[Tin Can]

I treat all chem as deadly poison

Even food grade citric acid for stop

Watch out for kids of any age

[Doremus Scudder]

I have a quadruple-beam balance scale and digital scales that I use for mixing film developers, etc.

That said, for the print developers I use (D-72, ID-62 usually and a couple softer-working ones I use occasionally), I have spoon recipes. Fast and precise enough. If I'm printing for a couple of days or more, I'll mix up stock solutions. If not, I'll just mix enough for the session. I rarely need vessels larger than two liters; I'll mix a stock and add water to the tray when I need more.

Some things I find easier to keep as pre-mixed solutions of individual chemicals. I have 10% potassium ferricyanide, 3.5% potassium bromide, 10% sodium carbonate and 1% benzotriazole around all the time. They get used for mixing bleaches, mixing (and doctoring) print developers, etc.

Somewhere here or over at Photrio I've posted my spoon recipes.

Best,

Doremus