Finding the edges of Eukobrom AC will hurt your pocket.

One open ,One untouched.

I have some good and bad news concerning Tetenal's Eukobrom AC. I have been pushing the developer to find it's limits. Without knowing where the edges are you cannot be sure that you are getting the optimum usage.

The good news is that two litres of diluted developer at 1 to 9 stored in a slot processor will remain usable for up to six weeks. Obviously this will vary depending on your circumstances. Also as the developer gets older the solution becomes more brown. Along with this it imparts some of this colour to the photograph by producing a subtle chocolate brown warmth in this case with Kentmere select RC gloss. A paper I have been using alot.

Used and depleted

The bad news is, while I have been involved in seeing how long a working solution will last, I forgot to mark the stock bottle with an 'opened on date'!. As a result 800 mls of unused developer has been thrown away. The first time I have had to do this ever! 

    

 I discovered this 'error' at the start of a printing   session. The existing developer was tested for   usability and found to be no longer viable. So I   made up a new batch to find that this was also   depleted. I was suspicious that the open bottle   was off by the colour but made up a new batch   anyway. In the past with other traditional   developers the colour does not always indicate   that it is exhausted. It took time to find out for   sure as the new developer was producing a very   soft test image without any contrast. I was using Kentmere paper, not known for being on the soft side and very quick to produce an image when placed in the developer, seconds in fact. In this case it still was not right after two minutes. After several attempts it was dumped. Not impressed to say the least.

Continence from open
bottle

Test Prints from open bottle of Eukobrom AC 

Not to worry I had a new unopened bottle. However on pouring the new bottle into the measuring jug this was brown in colour as well. Not the slight orange colour I was expecting. Now I was angry. I made up a batch anyway and to my surprise I was met with a well developed test image. Fully toned, great!

It took over an hour to get to this point what with one thing and another. My temper mellowed as each successive photograph left the developer fully toned.

Developer from fresh
bottle

Developer from
fresh bottle.

Test print in fresh developer..

Will I use the developer again? I still have the best part of a litre left from a dodgy opened bottle that has an 'opened on date'. As long as the contents are viable I will use it again. As to re stocking it? Not sure? It is just as well I keep some of my old friends in stock.

I did email Tetenal a long time ago to find out if they had any suggestions as to why this should be the case but have had no answer, I can share with you at the point of writing there is still no answer on posting.  

Printed on Kentmere RC gloss paper developed in Tetenal Eukobrom AC

This post was first published in 2017 there has not been any response from Tetenal on my concerns to this date.

Alternative way to check your fix is still fresh.

Here are two simple and easy ways of checking that the fix is not exhausted. The bottom line is if in doubt, throw it out.

1. Take a drop of fix and place it on some blue litmus paper, if it turns red the fix is still active, if the paper remains blue it is exhausted. Rapid acting fixes by their nature will get exhausted more quickly than an ordinary one. When fixing paper you may expect to get thirty to forty 18 x 24 cm ( 8”x 10”) sheets per litre.
2. Take ten ml of fix and add ten drops of potassium iodide solution to the measuring jar and stir. If the milky solution does not clear after it has been shaken then the fix is exhausted and a new batch should be made up. If it clears the fix is OK to use. Make up your Potassium iodide solution from two point five grams of powder and add a thousand ml of water and mix. This method does not apply to rapid fixes.

These methods will work for your film fixes as well. But the milk test you do for film will not work with paper as you cannot see this stage with paper.

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.