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Showing posts with label water. Show all posts
Showing posts with label water. Show all posts

Wednesday, 4 January 2012

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.

Thursday, 15 December 2011

Drying agent?


This is the final thing you do before hanging up your negatives to dry. This helps with the drying process by reducing the water tension allowing it to run more freely and minimising drying marks caused by the lime in the water.

Add three or four drops of wetting agent to the developing tank. Agitate the spiral in an up and down motion for a few seconds and leave for a minute. A further refinement is to add wetting agent to de-ionised water and transfer the spiral to it. Take the spiral out and peal the film from its grip or separate the two halves whichever you find easiest to do.

Wednesday, 14 December 2011

Washing your negatives


This is just as important as the developing, stop bath and fixer. The temperature of the water needs to be close to that of the previous process of 20 degree C.

The purpose of washing is to remove the last of the fixer from the emulsion and needs to be done thoroughly to ensure the longevity of the negatives.

Which method to use? One way is to empty the tank and refill with fresh water and agitate for a few seconds, this should be repeated several times. Another way is to use a wash hose that is specially made to fit into the top of the developing tank and attached to the tap. I personally favor this approach with my own refinements: after fitting the hose in place I open the tap till it is nearly fully open and leave for thirty seconds, this vigorusly removes the last of the fix that remains. Then slow the flow right down for the next ten to fifteen minutes. It is a simple straight forward procedure that has served me well over the years.