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Thursday, November 2, 2017

Turning it easier

In the last post, I spoke about Bill Williams color developer, as he proposed it.

To mix all components, one by one, each time you want to develop a film, is not that practical. Besides, with those 10% or 1% solutions you have to measure different amounts of each. I thought it would be easier to have only two prepared stock solutions and use equal amounts of them, just like a commercial developer.

So, here is my proposal for an easier usage of Bill Williams developer:

Stock solution A, for 500 ml

25g Sodium Sulfite
20g CD4 *

Stock solution B, for 500 ml

12,5g Potassium Bromide
0,1g Potassium Iodide
200g Potassium Carbonate

* The resulting amount in the work solution is slightly higher, 0,4g against 0,35g

Usage:

Put 10ml of each solutions A and B in 500ml hot water from tap (+/- 50ºC), mix and let it cool to 45ºC (112ºF). Pour the solution into the tank, where the film was previously loaded. Gently and constant agitation during 8 minutes. Then rinse, followed by bleach, rinse, fix and wash, as usual.






Saturday, October 28, 2017

Bill Williams CD4 Color Film Developer

Published in May 21, 2008 by Bill Williams at APUG, here is his recipe:

«Water 500ml @ approx 112 degrees
Sodium Sulfite (A) .5 grams (approx 1/8 tsp)
CD4 .35 grams (approx 1/8 tsp)
Potassium Iodide 1.8 milligrams
Potassium Bromide .25 grams
Potassium Carbonate (A) 4 grams (approx 2/3 tsp)»

The recipe is very minimal and precise about the amounts in grams and apparently  not accurate with fractions of tsp. But reading above the recipe, one can understand what he means. He used graduated inox recipients to measure exact solutions of Potassium Carbonate, Sodium Sulfite and Potassium Bromide. I only don't understand how he measured Potassium Iodide from a 1% solution.

I prepared following separate 500 ml each solutions:
  • 50 grams CD4 and 1,5 grams Sulfite as preservative only
  • 50 grams Sodium Sulfite
  • 50 grams Potassium Bromide
  • 50 grams Potassium Carbonate
I already had a 2% solution of Potassium Iodide. So I took 5 ml (that contains 100 mg) and add water to make 100 ml, so I ended with a 0,1% solution. To use 1.8 mg, I need 1,8 ml of this solution.

With a 5 ml syringe, I measure following amounts to prepare 500 ml of this developer:
  • 5 ml Sulfite 10% solution
  • 3.5 ml CD4 10% solution
  • 1.8 ml of Iodide 0,1% solution
  • 2,5 ml Bromide 10% solution
  • 40 ml Carbonate 10% solution
One of the last results

Sunday, October 22, 2017

One shot C-41. Is it a good idea?

I have been using Dignan NFC-41 developer for quite a long time, but there are some negative points that I couldn't resolve until yet: the first bath doesn't last that long, after the tenth development in a weekly basis, you already see thin negatives; the color shift to green in negative (magenta in positive) is possible to fix but somehow annoying. Another opinion that may be right is that modern films have thin layers and cannot hold enough CD4 to the second bath. I have tried to extend the times for both A e B baths or to put a few ml of bath A in bath B.

The great expected advantages of Dignan method for amateurs are: no need of temperature and cost reduction by using only small amount of CD4 each time. The first advantage, if you want to get better colors, will disappear because maybe you need to use temperature. The second advantage did not prove because the first bath goes bad within some time. Unless you develop every day, you will not save much money with the developer.

I already though about just using a mixed developer (A+B) in a one shot developer using temperature. But the problem of the shelf life of bath A would still exist.

Further searchs at internet, lead me to this very clever suggestion of Bill Williams at APUG.

I already have results of using it. Unfortunately, I made a small mistake, using more carbonate than proposed. Nevertheless, the pictures showed great potential. Maybe next time will be even better.











 

Wednesday, August 16, 2017

Homemade gravity shutter

It is very easy to make a pinhole camera. But if we want to make a film camera with scars means, the more complicated part is, obviously, the shutter. I already made some rudimentary shutters using rubbers, wood and aluminum plates, without a concrete project. There are several types of shutters, see here. First of all I wanted to make a simple one, and this time I decided to plan it more in detail.


It is a single leaf shutter with 3 mouvable partes. The leaf, the catch mecanism that keeps the leaf covering the hole and the trigger that will push the leaf when it is released by the catch.

It uses two springs that I took from used ballpoint pens. Afer finishing the project I realized that another piece was needed to keep the leaf close to the square wooden base, whose dimensions are 5,7 x 5,7 cm. Also the hole resulted a little too large, due to the file I used to enlarge it, after drilling a a smaller hole with a home driller.

The next time, I will know more about these problems and maybe it will work better.
  


Wednesday, July 26, 2017

Salt as a fixer is spreading

As soon as March 2012, I rediscovered salt as a possible alternative to known thiosulfates fixers.

A 300g/l solution of salt will fix normal B&W films in about 24 hours.

After that date, I started a series of tests in order to make the salt fixer faster.

I came to the conclusion that adding 2ml/liter of a 5% solution of household ammonia to the salt fixer, the time is reduced to as few as 2 hours. In this recipe I also included 2g/l of Potassium Bromide which also contributes to the speeding of the salt fixer. But it may be left away, if time may be longer than 2 hours, let us say 4 hours. Also Potassium Bromide is not a household stuff and this is actually the aim of the thing, no need of expensive products and hard to get!

It is already 5 years ago that I published the 'finding' and slowly this is spreading away.

Early recognized by the Caffenol Master Reinhold, that promoted some discussions about it in forums,  I am glad to see that my modest contribute to homemade film development is beeing announced here and there. I found it today at the fine blog of Profesora G. J. Yukavetsky.

My compliments and special thanks!

Thursday, July 13, 2017

Dignan 2-bath and Betadine

My last modification of the Dignan 2-bath developer in order to get better results, at room temperature, is as follows:

Bath A

500 ml water
9 g Sodium Sulfite
1 g Potassium Metabisulfite
11 g CD4
Water to make 1 liter

pH should be acid
Time duration: 10 minutes (or more)
Note: Keep bath A in a dark bottle to prevent oxidation and reusage

Bath B

500 ml water
25 g Potassium Carbonate
0,6g Potassium Bromide
Water to make 1 liter.

pH is aimed to be about 11.
Time duration: 10 minutes or longer with constant (non stop) agitation for less grain.
Bath B may be one shot or reusable. No rinse or wash between bath A and B.

After bath B, a stop bath with 40ml of Vinegar per liter water is good to prevent basic contamination of the bleach bath and fixer.

And now, which bleach bath is suitable? Ferric(III)-Ammonium EDTA based bleach is good and Ammonium Thiosulfate as fixer is also a good option. But there are some more alternatives like Ferricyanide and Copper Sulfate & Salt for the bleach and Sodium Thiosulfate (Hypo) for fixer.

What only few people know is that Povidone-Iodine (sold under the brand Betadine) may also be used as bleach. Using a 10% solution of Povidone-Iodine, it takes about one hour to act. Like other bleach baths, it also needs aeration to work better.

Some examples of photos developed with the modified Dignan 2-bath as above, bleached with Betadine and fixed with Sodium Thiosulfate based fixer. The fixer also needs much more time to act, also one hour.






Conclusion: Betadine (Povidone-Iodine) works very well (IR scanning didn't show any remaining silver) and Sodium Thiosulfate works well too, both need much more time than regular accepted bleach and fix baths.

Monday, June 19, 2017

Parodinal, another alternative

Parodinal is a clone of the famous developer Rodinal, from AGFA. It has a very long shelf life and can be used in concentrations from 1:10 to 1:200. However, when diluted it should be used in the next hours. It may be used for paper in the strongest concentrations and for film or plates for the more diluted baths.

Taking this formula as starting point, let us translate it to 500 ml, doubling the contents:

30 g Paracetamol
100 g Sodium Sulfite
40 g Sodium Hydroxide

I had many difficulties to get Sodium Sulfite at local suppliers. So, I started thinking about alternatives using Potassium Metabisulfite instead. Using a chemical balance calculator like this one, I realized that following equation is valid:

K2S2O5+NaOH = SO3K2 + SO3Na2+H2O

The first term is Potassium Metabisulfite and Sodium Hydroxide and the second is Sodium and Potassium Sulfite and some water.

From 80 g Potassium Metabisulfite and about  30 g Sodium Hydroxide, one gets about 100 g Sulfites that may replace the 100 g Sodium Sulfite given in the formula above. This leads to following new recipe:

30 g Paracetamol
80 g Potassium Metabisulfite
70 g (40+30) Sodium Hydroxide

It works very like Rodinal, same times and dilutions.

Following photos were made with an Agfa Clack camera, using Ilford Delta 100, developed with this last recipe in dilution 1:100 for 60 minutes in stand development: