Thread: Colour Printing
View Single Post
  #8  
Old 11th October 2020, 09:59 AM
John King John King is offline
Friend
 
Join Date: Nov 2012
Location: County Durham
Posts: 3,318
Default Mixing RA4

Initially I make 3 litres of developer and blix. 2 litres fill each individual slot to start off with. The remaining litre I split down to 5 x 100cc glass screw top bottles and 1 x 500cc glass bottle. Only 2 litres have the 'starter' included.

When the first 5 x 100cc bottles are used I then decant that into the smaller bottles.

Once I have decanted the 500cc bottle I make another 1 litre and put that into 2 x 500 cc bottles. so on and so forth

As an experiment, with C41 developer which will go off a lot quicker than RA4, I have tried mixing 1 lire at a time and then decanting that into 150cc glass bottles which is the quantity needed for a JOBO processor. These are then heated in the Microwave (Shh don't tell the boss).

The the caps are fitted when the liquid is hot(ish) - about 50C seems to be about right, so when they cool there is a partial vacuum and the liquid shrinks in volume reduces the oxygen levels This appears to be like a lot of work but it appears to work. last Friday I developed a film with pre-mixed developer that was over a month old, it had only slightly discoloured and there were no issues with density or colour balance. I only use the developer once then discard, perhaps not as economical as it could be but it ensures a set standard.
Reply With Quote