xtol development times adjustment for low volumesgreenspun.com : LUSENET : B&W Photo - Film & Processing : One Thread
XTOL film development times need adjustment for small tank volumes.
It is a common complaint that the development times given by Kodak for XTOL are much too short to give satisfactory negatives. I believe the times given by Kodak are correct - provided they are properly adjusted for 'capacity' (and, of course, dilution, temperature and exposure) as per Kodak's Data Sheet. If you adjust properly you get excellent negatives with most films.
It seems many users forget to consider the capacity factor, indeed some magazines have published development times for 1+1 dilution without mentioning the quantity used per roll. Such unspecific development times are nonsense because the quantity of undiluted Xtol used to develop one film is a very important factor for determining the development time.
Kodak states that 15 rolls of film can be processed per litre of Xtol Developer (AND THEY MEAN UNDILUTED DEVELOPER!), but that you have to increase the normal development times by 15% if you develop 6 to 10 rolls per liter, and by another 15% (or 33% in total) if you develop 11 to 15 films per litre.
Here is a sample calculation: My tank requires 250 cc liquid per film and I use a 1+1 dilution. That equals 125 cc undiluted developer per film and I therefore develop 8 films per litre and need to increase the standard time for 1+1 dilution by 15%. --- If you rotate your tank, 150 cc liquid or less is usually standard. If you use 150 cc 1+1 dilution you develop 13 films per litre and you need to increase development times by one-third. That makes a lot of difference!
Jobo USA (the tank manufacturer) have made some tests on minimum quantities needed per film and have concluded that certain films (e.g Agfa) need more developer per film than Kodak and Ilford, so you may want to test the adjustment percentages before you develop a valuable film.
I find XTOL an excellent developer, and pleasant to work with. Ilford Delta 100 has long been my favourite film. Luckily enough these two products work superbly together. I use this combination up to an exposure index of 800 and in spite of the pushed development it gives better result than high speed films.
Pushing to an e.i. of 800 and using a 1+1 dilution gives a development time of 20 minutes at 200C which is inconvenient. Time is cut to 15 minutes when temperature is increased to 240C. Has anybody tried XTOL at high temperatures? Please let me know how grain, sharpness and gradation is affected vs. normal temperature.
-- chris almqvist (email@example.com), February 04, 1998
I use diluted Xtol at 75 deg. F in Patterson tanks. For 120 film I dilute 1+3, that's 4.5oz(133ml) Xtol + 13.5oz water per roll. For 35mm it's 1+2 dilution, 3.5oz(105ml) Xtol + 7oz water. I use a diffuse enlarger and develop films about 10% longer than the Kodak chart times.
Grain is ever so slightly smoother undiluted or at 1+1 but I am happy at the higher dilutions, except TMZ, which I develop at 1+1.
-- Tim Brown (firstname.lastname@example.org), February 10, 1998.