[Leica] Hints on JOBO auto processing.

[red735i at earthlink.net (Frank Filippone)]

No you can't upgrade without selling your first born.  But I am not so sure
on programming... best ask.

 The rest of this detail is written because of the specific series of JOBO
processor that you have.   It is not true for any processor except the ATL
500, 800, 1000 or 1500.

Now that I know what processor you have, I will warn you that you are
restricted to the tanks you can use, and you do not use the red ring on most
JOBO tank lids.   I am pretty sure you must use only the 2500 series of
tanks.  No 1500 series and no 3000 Expert series.

Then it is even more crucial that you watch out for developer exhaustion.
JOBO will tell you that you can process in a model xyz tank using only 10mL.
Fine, but that is the amount of fluid needed to cover the film in rolls or
using the 3509 reels, sheet film.  That is NOT the amount of chemical that
you need to get the development to be made properly. As long as you pay
attention to this parameter, you will find the JOBO to be a really great
method to attain process consistency.

Using the worst case situation, the 2553 tank plus the 5 35mm or  6 120
reels, this is the equivalent of 5 or 6 equivalent 8x10 sheets of film.  ( I
used the 8x10 sheet because that is the standard measure used for figuring
developer or fixer exhaustion).    For example, I have noted that it takes
40mL of concentrated TMAX RS developer to not be exhausted.  Using a
dilution of 1:5, that is 200mL of fluid per 8x10.  Using the maximum of 600
mL per run ( the max on the ATL1500 or 1000), that is only 3  8x10 or 3
rolls of film per run.  If you try more in the same solution, you will get
underdeveloped negs.  remember to calculate based upon the amount of
chemical concentrate per roll, times the dilution factor for liquid
developers ( HC110, FG7, Rodinal, etc.).  For dry developers, use the
correct amount of liquid per roll.

If you are using TMAX film or the Ilford or other equivalent, they are
really hard on fixer.  Use rapid fixer one shot, and use 200mL per roll.
Since I said this, rapid fixer is Ammonium Thiosulphate.  It washes out
faster than sodium Thiosulphate ( regular old fixer.)  Use the rapid stuff
and don't worry about the perma wash.  Also, you need to wash through the
chemicals in JOBO, and at least 5 rinse cycles is required for that.
Personally I use at least 10 cycles.  Read the JOBO lit and the Ilford lit
to get a better handle on this issue.

JOBO tech support in the USA is really first rate.  The person that knows
the most is .... Ken Ohwen...  khowen@aol.com

Frank Filippone
red735i@earthlink.net