Gregory Blank wrote in message ...
Jorge;

Out of curiousity , what does it do that normal
tray developing does not.



Just like everything in photography it has it's advantages and
disadvantages. Specially now that we have rotary development.

The advantage over tray developing is that you constantly replenish
the developer in contact with the emulsion, so results are very close
to those with rotatry development, with the advantage that you dont
suffer from laminar flows, which in many cases cause the streaking
with stainning developers in rotary and tray situations. Another
advantage is that you never take the film out of the soup, once again
diminishing the risk of getting streaking by oxidation of the
developer, a common problem with stainning developers ( with some more
than others, ABC is very suceptible to this, even with brush
developing I was unable to obtain consistent results)
You can use same size trays to develop the film, unlike tray film
where you need double the size tray to avoid uneven developing,
specially on the edges of the film. This might not seem to be a big
consideration if you are doing 4x5, but move to 8x10 and larger sizes
and all of the sudden you are wasting a lot of developer and space.
If you are doing 8x10 and bigger, shuffling is not as easy, try
shuffling 6 12x20 negatives on a 20x24 tray.... ;-)

The disadvanatge is that you can only do one at at the time, and that
is a lot of wasted time when you have 10 negatives. Frankly IMO I
would not do this for 4x5, I would get the BTZS tubes, they produce
just as good a result and with a little practice you can do 6 at the
time. It is what I do now for my 8x10`s. I bought the containers used
for storing welding rods, they are aweseom for tube developing, and
they only cost like 8 or 10 bucks each. 12x20 I still do by brush, I
cannot afford a Jobo, but I dont have more than 2 or 3 per developing
session, so it is not a big deal.