ME AND HOME BREW

Brian Asquith (Area 11).

When I first started with colour reversal film it was with Ferrania colour. I developed this is a Ferrania kit which came in a nice square box. Both the film and kit was imported by Johnsons of Hendon. Economy was the prime reason. I could buy the film in bulk and the kit from the local professional photographers shop. I soon realised however that the film was as good as the rest. This situation lasted for a long time and I have over 1000 slides still in good condition, taken and processed 20-25 years ago.

Colour films have improved over the period but these Ferrania slides compare well. I joined the Ferrania Club (CR50 Club) and was introduced to the official formula via the Club. This was easily prepared formulae taking two hours to use. The temperature was a convenient 68F and you could watch TV while you leasurely did the business. None of the frantic clock and temperature watching of today.

Then started the upheavals. Ferrania became part of 3M who altered the film but did not supply an official kit or formula. The Club became 3M and a search began for a formula; never short of boffins, two members I remember worked hard to crack the new films. Will Griffiths and Gilbert Mathewman.

I met Gilbert t his home and at the local camera Club, he produced an E4 formula and Will, who I had long correspondence with, produced eventually, the Lingcolor kit. These formulas worked well until the films were again changed.

Over the years my photography grew wider in its scope with lectures and A/V shows I was using a lot of film. I dropped out of the 3M Club as it became, fast, another arm of commercialism, and started to use kits. I have used all types of films and most of the kits. Now we have reached the stage where all films are supposed to be basically the same E6. But anyone who has compared different makes exposed under identical conditions will see a difference in colours, sometimes this can be very marked. The difference when seen in isolation is acceptable and taken as accurate re`production of the colours of the scene etc. Which it is not. Photograph a colour chart then compare, at least one colour will differ slightly.

However this is not important as we all see colours differently anyway. I have always looked for films that give good colour to my eye and importantly a good black. Agfa RS 50 and Agfa 50S developed in Chrome 6 met the bill. At £13 for 18 films it also seemed economical. Then Agfa film crept up in price and I had a problem with the bleach/fix.

I decided perhaps a change was due, I re-joined the Colour Reversal Club as it now is, got some good advice on the possible bleach problem. I was impressed with the Newsletter and the amount of information therein, also the scope of things covered, not just reversal film but most things covering real photography. Also the boffins were still hard at work trying to find the latest formula to suit the film.

It seemed to make sense having lots of basic chemicals in use as I make up all my own brews for colour neg and printing to start making up the new formula and using Konica film. I have had my failures with kits and home brews finishing up with some weird and wonderful casts. Time is limited so I did not want to get into the experimental stage. However the satisfaction of mixing a formula and it working is a very nice experience.

I read with great interest the trails and tribulations that our contributers go through. I am full of admiration at the time and effort they put into their hobby and that they pass on this information to me. Over the years it has enabled me to understand the basis of the colour reversal process without taking a course in photographic chemistry! So with such background of none technical expertise I pass the following comments on the Club`s home brew for E6.

The actual mixing up for 500ml is a real bind. I use a balance and weights so fractions of a gram are a fiddly job. Is 2mls of Pot. Iodide, instead of 1.95ml, going to make that much difference! I know Pot. Iodide is one of the trace chemicals that does influence colour, but 00.5 of a gram, surely not. 6.1gm of bicarbonate, why not 6gms, 1/10th of a gram cannot surely make so much difference. Then 9.55 grams of Pot. hydroquinone monosulphonate! and thats only the first developer! How does one measure 0.825 of stannous chloride in the reversal bath?

The problem becomes less when mixing 2 litres. But is it all so critical. I suspect not. As errors tend to cancel each other out as does purity of various chemicals. Slight inaccuracies of weighing and the quality of the water etc, if these effects the results so much we have no chance of getting consistent results. Is it such a precise science that we need worry about 00.5 of a gram!

I have never used a pH meter. I use pH indicator strips as a rough guide. I see the outlay of so may pounds for a meter as not justifiable for a small time user. Because the whole process has been speeded up by use of higher temperature, it takes as long to get the temperature up as it did to do the job at 68F. I control the temperature in a water bath with a tea making immersion heater. The temperature varies + or - 5 deg. timing adjusted to accommodate the fluctuation. The process is quick and easy.

Agfa 50S was a wee bit warm in colour, a good black. Konica shifted to yellow, and a trial of out-dated Barfen (Fuji)? good colour but a weak black. A cut in 1st. development time improved the black. Unhappy with Konica film I sent results to Lawrence Edwards for comment, he was encouraging re Agfa, made suggestions for Konica.

I read of a problem with the reversal bath. Why bother with chemical reversal anyway. I would revert back to white light exposure after a stop bath. After all the night is set aside for processing so an extra 5 minutes is not going to be much. If I use my solutions again I always filter them through a funnel with a piece of cotton wool. It is surprising how much sediment is removed.

In conclusion I would discourage anyone to invest in a balance and chemicals to process the odd film. If on the other hand you do your own W&M, Col. Neg. etc it`s worthwhile doing reversal processing at say, 18 films a year (30 metres) and to have a go at home brew reversal. I have produced good results fairly consistently once satisfactory formula has been found.

I think Lawrence Edwards must be congratulated along with others before him in providing the club with yet another working formula.