Re: [APML] D-19 Development Question

["westergren" <westergren@netzero.net>]

Allan,

Splitting up the D-19 will work, but be careful.  The packages you store in
the bags in the freezer will have been exposed to oxygen (air) and humidity
(water).
The longer they are stored, the more chance of chemical change.  Before
using any stored package, inspect it to see that the D-19 powder is still
pure white.  If it has a brownish color, it is bad.  I speak from
experience.  The anti-fog chemicals in the D-19 apparently are the first to
deteriorate.  I tried a slightly brown batch and got significant fogging in
both the exposed and unexposed areas.  The fogging was uneven.

I have stopped trying to save on the cost of D-19.  The gallon package costs
a bit more than having a roll of film developed, but not that much more.  I
prefer to have absolutely fresh D-19 to develop the Tech Pan, to be sure
that my hours of exposure and guiding aren't wasted.

One other note.  I process my hypered Tech Pan 10 minutes at 68° in the
stock D-19 diluted 50-50 with water.  Kodak says that gives the maximum
contrast. This is the opposite of what many APML desire by using HC-110,
which decreases contrast a bit.

Don


> Hello,
>
> I'll be trying some galaxy shots on 35mm Tech Pan in the coming weeks
> and they will be developed with D-19. I just purchased the D-19 mix and
> have read in the APML archives that the powder can be broken into
> portions and then stored in the freezer  - mixing for development as
> needed.
>
> My development tank uses 11oz for a single roll -  so my math shows
> that I should be able to get 11 tanks of 11.64 oz out of the mix (the
> package says the whole thing makes 1 gallon and there are 128 fluid
> oz's in a gallon). I just want to verify with the guys that do this all
> the time that I'm thinking correctly. Just break the mix into 11 equal
> portions and add 125 degree water to each to create 11.64 ounces and
> I'm good to go for development at the correct concentration - right?
>
> Thanks for the assist,
>
> Allan Whetzel
>
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