Trouble in the darkroom

My darkroom is a very personal space, the only acknowledgement to it being standard is the separation of wet and dry working areas. It is just big enough for one person to work in comfortable. A bit of a glorified closet really! which has meant I have had to find ways of making the space work hard to meet the needs of both wet-and dry sides working areas.

One of the things I have had to do is to put the 12 x16 paper processor under the work top on a pull out shelf. It was done originally to save space but has proved to be inspired in a way I had not foreseen. Being able to look down on the print process has made it a more relaxed way to work. Keeping the work top clear for other wet side needs has not worked so well, the top is being dominated by the tray I use to put the tube covers that keep the chemicals fresh in the slot processor. It was a large tray so that the tops could be spaced far enough apart to stop cross contamination. 

However, it all came to a head when I wanted to try a new print developer and use it with a tray so I could monitor when the first signs of the image appeared, then transfer it to the processor for stop and fix. I should explain that the darkroom does not have running water. I usually part fill a tray with water to put the fixed photographs in then wash them at the end of the session in the bathroom. Anyway I had the water tray precariously balanced on top of the slot covers in their tray as the rest of the top was taken up with the developing tray. It must have been a good day as I did not manage to tip the whole lot over myself. 

I now seriously considered ways of storing the slot tops that would keep the worktop clear. It came to me that the best way was to stand them on end. My first thought was to use a number of metal clips attached to the wall. I cannot understand why I had not come to this conclusion sooner. Once I had thought about it. It was not such a good idea as fix attacks metal. I decided it would be better to use plastic, so took some measurements, sat down and did a number of drawings of a tray that would hold the tubes upright. Then thought about how to stop cross contamination, so added sections to the base. Once I had refined the basic look and measurements I showed the idea to my mate at Plasweld, he helped to simplify the design and added a splash back to stop chemicals running all over the place when loading the tops into the stand. 

A few weeks later the stand is finished. It works very well and has freed up lots of space on the worktop allowing me to work more safely. Such a simple idea that has made a big difference.

A typical layout for a darkroom

PMK Pyro solution part B.

As mentioned in this post the developer is divided into two parts as a stock solution. Part B is the larger quantity of the two and suffers from settlement where the powder comes out of suspension and accumulates at the bottom of the bottle. Before use, you should shake the bottle well so that it goes back to a milky colour. It would seem that the larger the crystals in packet B the more drop out there will be. I have not yet found a method that stops this.

PMK Pyro a working solution

I am no stranger to making up developers from powders into stock solutions. The first thing you notice is the very small amount it makes up. Next, it comes in two parts and last, the powder needs to be mixed into distilled/de-ionised water ( used for car battery top ups ).

Solution A mixes up as follows:

Pour 80 mls of de-ionised water at room temperature into a measure. Open the packet marked A inside there are two sachets, take the smaller one and mix that in until it dissolves, do the same with the second one. It is important that they go in, in the right order. Make the solution up to a 1oo mls once done pour into a small storage container.

Solution B

Pour 160 mls of de-ionised water at room temperature into a measure. Add the contents of packet B slowly to the water stirring all the time until dissolved. Then top up to 200 mls. Again pour into small storage container.

Some notes:

By the time all the powders are mixed in, the amount of top up will be very small. The distilled/de-ionised water helps it to stay fresh and will keep well in partly filled bottles. Solution B has a bit of drop out and will need to be shaken clear before use. Makes up to 10 litres of working developer.

Freshly made PMK Pyro

Making up a working solution:

A normal mix is as follows,

•   One part A + two parts B to One hundred part of water.

e.g: To make 600 mls of working developer. Measure out 500 mls of water add 6 mls of solution A then add 12 mls of solution B and top off to 600 mls and stir. It is important that they go in in this order.

Notes:

•   When you add part B to the water it will turn a straw colour, if this happens it's OK to use.

•   Working temperature should be 20- 21 degrees C depending on which make of film you are using. You can check this with Digital truths massive dev chart.

Used PMK Pyro
developer.You reuse this at the
end of the process to add extra
stain to the negatives.

•   Prepare everything else before you make up the working developer then use it straight away as it oxidises very quickly.

•   When you pour the developer out at the end of the allotted time the solution will be very dark brown.

•   It is a 'use once and throw away' developer.

•   It is not necessary to re-dip the film in the developer after it has been fixed to increase staining.

•   Make working solution up with filtered tap water.

Fixing negatives and papers

It is important to fix your negatives fully, this will ensure their longevity.

Fixing removes the last of any light-sensitive material from the negatives stabilising and securing the images so they can be viewed in day light. The temperature of the fix should be the same as the developer and stop bath, 20 degrees C.

Most fixers nowadays are rapid fixers supplied in liquid concentrate form and will complete the fixing process in about two to five minutes. (always check the instructions on the bottle) over fixing will start to bleach the negative. These fixers are usually suitable for film and paper. There is a chance in the case of warm tone papers that they may suffer from bleaching of their warmth with rapid fixers, it would therefore be better to use a more traditional fixer made up from a powder to ensure no loss of tone.

Stop bath

Does what is says on the bottle! It is used instead of a wash as it helps to prolong the life of the fix and stops the developing process straight away. You must be careful not to contaminate the developer with stop, it will destroy it.

Stop can be obtained in two types of concentrated solution. One is odorless made from citric acid and the other acetic acid with a vinegar smell which can be quite pungent if used for prolonged periods in the darkroom, when processing prints in trays. Both have a colour change indicator added to the solutions so you can tell when it is exhausted.

Dilute the concentrated Stop one part solution to nineteen parts water (or as instructed on the bottle.) say 50 mls stop to a litre of water with a process time of one to two minutes, you will not gain anything by extending the stop time it is most active in the first few seconds. Agitate for the first thirty seconds, this ensures the developer has been completely deactivated, then ten seconds in every minute if you stop for two minutes.

Developer shelf life.

The keeping qualities of photographic chemicals to a degree is dependent on the dilution of the mix. In the first instance you should always follow the manufactures recommendation when mixing stock solutions by only adding the chemical to that quantity of water thus giving you a known starting point. If you require a more dilute working developer you should only make this up just before you are about to use it. Once used it should be discarded.

Reusable developers are poured back into their containers when finished with. Each time you pour it back a little bit is used up, it is a good idea to keep these containers full to stop the developer going off. This can be achieved in several ways if it is a plastic bottle you can squeeze the air out just before you nip the cap up, add glass marbles to the bottle so increasing its level, use a concertina bottle or the plastic bag out of a wine box ( if using one of these make sure it has been thoroughly cleaned.)

Remember that developer that has been used is likely to go off more quickly. It is a good idea to keep a record on each bottle of how many film or prints and what format has been developed. When you think you have reached the maximum usage discard it and make a fresh batch.

Farmers reducer.

This is a follow on from my last post on reduction.

Over developed or over exposed negatives may need to be reduced to make them a better printing prospect. This is achieved with chemicals that strip silver from the final image. Like developing, reducing a negative requires practice so you get an idea of how much to take away. It is best carried out in a place that is well ventilated with diffused light so you can see the process at work. It is a good idea to pre-soak the film it will allow you more control by slowing the process down. With experience you will get to know at what point to remove the negative. The chemicals do not stop working instantaneously. Because you can repeat this procedure it is better to reduce the negative in small steps so as not to over do it.

Reducers can be supplied ready mixed or you can mix your own. The formula that follows is a proportional reducer for overdeveloped negatives:

Stock Solution A

• Potassium Ferricyanide 7.5 grams.
• Water 1 litre.

Stock Solution B

• Sodium thiosulphate (Hypo crystals) 200 grams.
• Water 1 litre.

Notes: Ferricyanide has good keeping qualitys if kept out of strong sun light. Once you have mixed the chemicals you should use immediately. If you are using a stepped method of reduction do not contaminate solution A with Solution B as it will stop working. Working temperature of 20 degrees. You can place a dry negative in solution A but will need to watch the process carefully for between 1-4 minutes then transfer to solution B for about 5 minutes.

Potassium ferricyanide is a poison. Avoid contact with your skin and do not breathe the fumes.