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Re: development for alt-process

Personal film speed (what you set your meter to) and development time (what
density range you need to match a given process) are not easily "given" over
the net.  There are too many variables.  How you develop (you use a daylight
tank, I use trays), the developer (you use D-76, I use HC-110).  Even
tougher, how you meter a scene.  I had a discussion with someone on this
list (Carl Weese, was this you??) about how our exposure indexes could be so
far apart.  It came down to what I saw as "zone 2 / deep shadow" and what he
saw.  Not the same thing. Gets even more confusing if I use a spot meter and
you use an incident meter!

So, without an "in person" teacher you can solve this a few ways.

If you are a relatively technical perfectionist type (that is me, by the
way): chose a "master" and follow the master's method.  Jeffrey has a good
method that is aimed at alt process, I followed Fred Picker like a disciple
in my early days, and .... sorry "brain freeze" .... the "Beyond the Zone
System" guy.... can't think of his name... he is probably today's number one
teacher of "by the numbers technically correct" zone system work.

If you are more of the "seat of your pants" type.  Just remember that AA's
famous words also work in alt, "Expose for the shadow, develop for the
highlights".  I would suggest setting your exposure index (your shadows)
first.  If your shadows are too dense you are overexposing, If your shadows
are too thin you are underexposing.  Once you've gotten that "half settled",
print a number of negs using the "middle contrast grade" of your process so
that the shadows and dark tones look correct.  Ignore everything else.  When
the prints are dry, look at the highlights.  If they are on average burnt
out, you are overdeveloping.  If they are on average gray and lifeless, you
are under developing.  Yes: this method disregards the fact that development
has a SMALL effect on film speed.

This "seat of your pants" method sounds easier, but actually takes longer.
You have the variable of different scenes, so your data isn't consistent.
"On a bright day, your contrast is fine, on a dull day it is flat".  The "by
the numbers" method explains this, the "seat of your pants" may leave you
confused.  Very good work has been done by people using any of the above
methods.  Hey: Edward Weston only used a meter a few times in his life, and
his son Brett didn't have much use for them either ;-)

Remember too, most processes don't need a "perfect" neg. Silver, platinum,
gum, and others give lots of range to "fix" or "interpret" a negative in the
printing stage.  With these methods, if you are close you are a winner!  If
your neg is 1/2 stop overexposed, just print longer.  Too flat, add more
contrasting agent.

For what it is worth: In trays, using HP-5, using HC-110, my platinum (50%
Plat, 50% pallad) dev time is 170% of my silver time.  My palladium dev time
(90% pallad, 10% plat) is 220% my silver time.  My cyanotype dev time is
130% of my silver time (cyan is very paper dependant).  I shot it at EI 200
for silver, EI 125 for alt.  For alt I find most films work well if a zone 2
exposure creates a full stop (0.3DU) of film exposure above base+fog.  I've
always been more comfortable with a dense neg.

Hope this helps.  Keep at it.  Once you get over this, you get to go out and
make pictures (much more fun).

-- 
Tom Ferguson
http://www.ferguson-photo-design.com

> From: sstoney@pdq.net (shannon stoney)
> Subject: development for alt-process
> 
> I am still working on figuring out a development time for negatives for
> cyanotypes and palladium.  Somebody suggested adding about 70% to my normal
> silver development times.  Does that sound about right?  For me, with TRi-X
> shot at 320 in D-76, processed in a daylight tank, that would be 12.75
> minutes.