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Monday, May 21, 2018

Thank you for waiting

Since quite a long time, I found no time to go on with my experiments on color photography. But I have been busy taken pictures and developing and scanning and publishing at Flickr.

After trying Dignan 2-bath method for more than one year, tweaking here and there, developing at room temperature, I may now say that it is a very good idea but it also has disadvantages. The bath A doesn't last that long as the author desired and you have to live with some color shift to green in negatives, magenta in positive.

Last October I came to another approach by Bill Williams, that I tried to simplify creating a 2-solutions color developer, like used in commercial color kits. But I was not so sure whether this would not conduct me at the end to a standard color developer, like many other fans of color film photography do.

So, I prepared 500 ml of a standard color developer that I am using since more than a month (six rolls and still going). I am using the developer with a start temperature of 42ºC (I don't have a JOBO device) and until now the results are very good for me. The recipe may be found here, for instance.

Some results of using the standard color developer:
















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!