maximum sharpnes

Film Photography & Darkroom discussion

Moderator: Keith Tapscott.

Jay DeFehr
Posts: 50
Joined: Tue Jan 24, 2006 8:40 pm

Homebrews

Postby Jay DeFehr » Fri Mar 31, 2006 1:13 pm

Keith,

.1g-500kg is one hell of a range! My own scale has a range from .01g-400g, which covers everything I do, with ease. You might find you'd rather have finer measurement at the low end of your range than the ability to weigh out hundreds of kilos.

Your chemical inventory will allow you to make a wide range of MQ and metol developers, for which there are hundreds of formulae published, for both film and paper, many right here at Digital Truth. You could even make a tanning/staining developer based on hydroquinone, if you are so inclined. I think you'll find there is nothing magical about pre-packaged developers, and I hope you find a formula that suits your work. Since this thread is ostensibly about sharpness, I recommend the Beutler's formula in the acutance category, here at Digital Truth. Good luck, and enjoy.


Keith Tapscott.
Posts: 506
Joined: Tue Jan 17, 2006 8:58 am
Location: Plymouth, England.

Re: Homebrews

Postby Keith Tapscott. » Sat Apr 01, 2006 4:30 am

Jay DeFehr wrote:Keith,

.1g-500kg is one hell of a range! My own scale has a range from .01g-400g, which covers everything I do, with ease. You might find you'd rather have finer measurement at the low end of your range than the ability to weigh out hundreds of kilos.

Your chemical inventory will allow you to make a wide range of MQ and metol developers, for which there are hundreds of formulae published, for both film and paper, many right here at Digital Truth. You could even make a tanning/staining developer based on hydroquinone, if you are so inclined. I think you'll find there is nothing magical about pre-packaged developers, and I hope you find a formula that suits your work. Since this thread is ostensibly about sharpness, I recommend the Beutler's formula in the acutance category, here at Digital Truth. Good luck, and enjoy.
I should have stated 0.1gram to 500 grams and not kilograms, thanks for pointing out my error Jay. There are a lot of formulas for certain applications which are not so readily available or in quantities that are too large for regular use, so some raw chemicals allow these to be made up only when required.
Geoffrey Crawley mentioned FX-1 in the latest issue of AP stating that the inclusion of Potassium iodide is pointless with the films of today and was formulated along the lines of Willi Beutler`s high-definition formula for the generation of high acutance films that were popular at the time.
The developer can still be used today, but may yield flat results with certain films like 100TMX and he suggest about 25mg of Potassium Bromide instead. FX-2 is considered of more use for the latest films along with FX-37.
Cheers.

Jay DeFehr
Posts: 50
Joined: Tue Jan 24, 2006 8:40 pm

FX-2

Postby Jay DeFehr » Sun Apr 02, 2006 1:44 pm

Hi Keith.

I recommended Beutler's because you have the chemicals to make it. If you want to makle FX-2, you'll need to pick up some glycin. If you want to add chems to your shelf, there are many other developers I would recommend.

Jay

john botte
Posts: 1
Joined: Sun Apr 16, 2006 4:39 pm

Postby john botte » Sun Apr 16, 2006 6:45 pm

This message is for Jay DeFehr. Jay, can you give me the exact mixing formula with amounts for each chemical for the PC-TEA developer, I am a bit confused in your first explanation. Also if you can give some dev. times for films like Tri-X, Plus-X, HP-5 etc...

Regards,
John

Jay DeFehr
Posts: 50
Joined: Tue Jan 24, 2006 8:40 pm

PC-TEA

Postby Jay DeFehr » Thu Apr 20, 2006 1:49 am

Hi John.

The formula for PC-TEA, as per Pat Gainer, is:

TEA 70ml

ascorbic acid 9g

phenidone .2g

TEA to 100ml

add chemicals to 70ml room temp TEA and heat with stirring until all of the chemicals have dissolved (around 150F). Allow to cool to room temp, and top up tp 100ml. The solution will turn brown with age, but that's normal and does not indicate exhaustion. The concentrate wil last years on the shelf and provide consistent performance over its life.

To make a working solution, dilute concentrate 1:50 with water (20ml/liter)

Development times for HP5+ is 8:30/70F. I don't have times for TX or PX. Good luck.

Jay


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