How many volumn of solution do I need to smoothly process printpaper in a 12x16 tray?

In article ,
Peter wrote:


Generally speaking the runway behind you is of no practical use in an
airplane and the liquid (more than a few molecules) above the paper is
not of much use, either. Still, you have to keep it evenly wet and
circulating (normally with intermittent agitation) for even
development.

Are you using your developer one-shot, or reusing it? With such small
solution volumes you run the risk of changes to the paper's characteristic
curve because the developer itself can become exhausted over the course
of developing a single sheet of paper, giving different contrast in shadows,
midtones, and highlights.

--
Thor Lancelot Simon

"The inconsistency is startling, though admittedly, if consistency is to
be abandoned or transcended, there is no problem." - Noam Chomsky

"Steven Woody" wrote in message
...
On Apr 30, 10:54 pm, (Thor Lancelot Simon) wrote:
In article
,

Peter wrote:

Generally speaking the runway behind you is of no practical use in an
airplane and the liquid (more than a few molecules) above the paper is
not of much use, either. Still, you have to keep it evenly wet and
circulating (normally with intermittent agitation) for even
development.

Are you using your developer one-shot, or reusing it? With such small
solution volumes you run the risk of changes to the paper's
characteristic
curve because the developer itself can become exhausted over the course
of developing a single sheet of paper, giving different contrast in
shadows,
midtones, and highlights.


oh.. i thnk i lost the answer. i think i should ask this way:
what's the usual height of solution required for smoothly develop
16x20 papers in tray? i hope this way you experts can understand me
better.



There are two answers:
1. You have to use enough chemistry to make the chemical reaction work. With
most developers, this isn't an issue, but with very small quantity of
developer it is possible to exhaust the chemical after a lot of prints. The
manufacturer's specifications will tell you how many prints can be made with
a certain amount of chemical.
2. You have to use enough chemical to quickly wet the paper. If you use a
very small amount, it will be difficult to get the developer to flow over
the entire surface evenly.
My trays have very tiny ridges on the bottom. I like to have at keast about
1/2" of developer in the tray. (I use developer one-shot and throw it away
after a session). I like to have the stop bath and fixer trays nearly half
full. I re-use those chemicals.

On 5/1/2008 3:06 AM Steven Woody spake thus:

On Apr 30, 10:54 pm, (Thor Lancelot Simon) wrote:

In article ,

Peter wrote:

Generally speaking the runway behind you is of no practical use in an
airplane and the liquid (more than a few molecules) above the paper is
not of much use, either. Still, you have to keep it evenly wet and
circulating (normally with intermittent agitation) for even
development.

Are you using your developer one-shot, or reusing it? With such small
solution volumes you run the risk of changes to the paper's characteristic
curve because the developer itself can become exhausted over the course
of developing a single sheet of paper, giving different contrast in shadows,
midtones, and highlights.

oh.. i thnk i lost the answer. i think i should ask this way:
what's the usual height of solution required for smoothly develop
16x20 papers in tray? i hope this way you experts can understand me
better.

Since nobody else here can seem to understand, let alone answer, what's
basically a simple question, might I suggest that you answer it
yourself? Assuming you have the trays you want to use, just fill them
with water to the minimum height you think you'll need, then pour out
the water and measure it. (If you don't actually have those trays, then
you'll have to do a volume calculation, based on the area of the tray
multiplied by the height of the developer solution, which you can again
determine empirically.)

This is what you wanted to know, right?


--
The best argument against democracy is a five-minute
conversation with the average voter.

- Attributed to Winston Churchill

On 5/3/2008 6:38 PM Steven Woody spake thus:

On May 2, 1:57 am, David Nebenzahl wrote:

Since nobody else here can seem to understand, let alone answer, what's
basically a simple question, might I suggest that you answer it
yourself? Assuming you have the trays you want to use, just fill them
with water to the minimum height you think you'll need, then pour out
the water and measure it. (If you don't actually have those trays, then
you'll have to do a volume calculation, based on the area of the tray
multiplied by the height of the developer solution, which you can again
determine empirically.)

This is what you wanted to know, right?

Dear David, I think you don't understand. My problem is actually that
I am not sure what the solution height is safe to smoothly processing
paper. I want to use 1mm to get minimal soution volumn, but everyone
knows that 1mm is not safe, I can use 30mm to ensure it's safe, but
you know 30mm means almost 4 liter for a 12x16 tray. So, my question
is just the solution height, without the heigth, I can not do any
experiment or calulation. By reading replies in this thread, I now
think 12mm is a safe solution heigth. So, I need 1.5 liter for 12x16
or 1.2 liter for 11x14.

I still don't see why you can't determine the volume you need by simple
experimentation; you only need enough solution to cover the paper
completely, which should be very easy to determine visually. Forget
"solution height" in mm; just figure out how much liquid it takes to
completely submerge a piece of paper. We're not talking about
high-precision processing here.


--
The best argument against democracy is a five-minute
conversation with the average voter.

- Attributed to Winston Churchill

In article m,
David Nebenzahl wrote:

On 5/3/2008 6:38 PM Steven Woody spake thus:

I still don't see why you can't determine the volume you need by simple
experimentation; you only need enough solution to cover the paper
completely, which should be very easy to determine visually. Forget
"solution height" in mm; just figure out how much liquid it takes to
completely submerge a piece of paper. We're not talking about
high-precision processing here.

Forget reason some people- especially "photo" people are anal in the
worse ways.

--
Reality is a picture perfected and never looking back.

"____" wrote in message
...

Forget reason some people- especially "photo" people are anal in the
worse ways.

In precisely what worse ways? In excruciating detail, please.

On 5/5/2008 7:50 PM Pico spake thus:

"____" wrote in message
...

Forget reason some people- especially "photo" people are anal in the
worse ways.

In precisely what worse ways? In excruciating detail, please.

Wrong newsgroup for that.


--
The best argument against democracy is a five-minute
conversation with the average voter.

- Attributed to Winston Churchill

"David Nebenzahl" wrote in message
s.com...
On 5/5/2008 7:50 PM Pico spake thus:

"____" wrote in message
...

Forget reason some people- especially "photo" people are anal in the
worse ways.

In precisely what worse ways? In excruciating detail, please.

Wrong newsgroup for that.

ooooh. Wrong darkroom.