Musings on washing fiber-based prints

On 2/28/2005 12:50 PM Claudio Bonavolta spake thus:

David Nebenzahl a écrit:

Just wondering, dreaming of the day I might actually try to make prints on
"real" (i.e., fiber-based as opposed to RC) paper ...

So, as most of us know, one of the big problems with FB is washing. And
one of the things that turns me off of using it is the enormous quantity of water
normally needed for adequate washing.

So ... how about if a guy were to build some kind of recirculator, complete
with filtration? Maybe a big (5-10 gal.) tank with some kind of filter,
like activated charcoal? Would such a filter be capable of removing enough
residual hypo to be worthwhile? That way you could wash with a reasonable amount of
water, using a small pump to circulate the water through the print
washer and filter.

The filter's the main thing I need help with, being relatively
filter-illiterate. What do the chemist types here say?

(I'm already assuming a thorough hypo-clearing bath before washing.)

Or has someone already thunk this up and they're available for $29.95 at
B&H?

Available at B&H for $29.95 certainly not but (advanced) aquariophiles
use reverse osmosis filters for their fragile fish:
http://www.hydrationtech.com/Osmosis...r31703doc3.pdf

Still not sure this will filter out fixer.
Not sure it's a good idea unless you live in the Sahara ...

Unfortunately no: from the white paper:

"Osmotic filters are unlike other filters in that they produce a nutrient
drink rather than simple water. This makes osmotic filters inappropriate
for producing cooking or hygiene water ..."

This system uses a "syrup" and osmosis to produce a safe drink from any kind
of water, including brackish or muddy water.

Looks like pretty good stuff for backpackers, though.


--
"I know I will go to hell, because I pardoned Richard Nixon."

- Former President Gerald Ford to his golf partners, as related by
the late Hunter S. Thompson

David Nebenzahl a écrit :
Unfortunately no: from the white paper:

"Osmotic filters are unlike other filters in that they produce a nutrient
drink rather than simple water. This makes osmotic filters inappropriate
for producing cooking or hygiene water ..."

This system uses a "syrup" and osmosis to produce a safe drink from any
kind of water, including brackish or muddy water.

Looks like pretty good stuff for backpackers, though.

You're right David: not the best example ...

Some other links, probably better:
http://www.gewater.com/library/tp/833_What_Is.jsp
http://members.tripod.com/%7Eurila/

and a search on Google with _reverse osmosis_ will take back dozens of
other sites (often manufacturers) ...

Not really practical anyway ...

--
Claudio Bonavolta
http://www.bonavolta.ch

David Nebenzahl a écrit :
Unfortunately no: from the white paper:

"Osmotic filters are unlike other filters in that they produce a nutrient
drink rather than simple water. This makes osmotic filters inappropriate
for producing cooking or hygiene water ..."

This system uses a "syrup" and osmosis to produce a safe drink from any
kind of water, including brackish or muddy water.

Looks like pretty good stuff for backpackers, though.

You're right David: not the best example ...

Some other links, probably better:
http://www.gewater.com/library/tp/833_What_Is.jsp
http://members.tripod.com/%7Eurila/

and a search on Google with _reverse osmosis_ will take back dozens of
other sites (often manufacturers) ...

Not really practical anyway ...

--
Claudio Bonavolta
http://www.bonavolta.ch

David Nebenzahl wrote:

I'm already assuming a thorough hypo-clearing bath before washing.


And I think likely assuming a slot type archival washer.
I think that if you could wash clean in fifteen minutes with
very little water, what ever the method, rotary, tray circulation,
still water diffusion, tray and agitation, or slot washer, a slot
ARCHIVAL washer would be your choice.
Apart from Mr. Knoppow's references to Kodak's reports of three
minutes in hca being about all the good that can come from hca, I've
read a post or two where ten or twenty minutes will reduce wash
times considerably. Mr. Miniter tested an alkaline fix which
gave clean results in ten minutes with constant agitation.
My point is that pre-wash research is needed. It's the fix
that needs to be washed out. That's the place to start. I'm using
A. Thiosulfate at 1:49 for prints and think doing so may be
a good prelude to the still water diffusions to follow. Dan

"David Nebenzahl" wrote in message
...

So ... how about if a guy were to build some kind of recirculator,
complete
with filtration? Maybe a big (5-10 gal.) tank with some kind of filter
[...]

That's an interesting idea. Before we get too far into this, let's consider
the water first; you do not want softened water for the primary wash.

"David Nebenzahl" wrote in message
...

So ... how about if a guy were to build some kind of recirculator,
complete
with filtration? Maybe a big (5-10 gal.) tank with some kind of filter
[...]

That's an interesting idea. Before we get too far into this, let's consider
the water first; you do not want softened water for the primary wash.

jjs wrote:



That's an interesting idea. Before we get too far into this, let's consider
the water first; you do not want softened water for the primary wash.



Why not?

-Peter
www.desmidt.net

On 3/1/2005 5:45 AM jjs spake thus:

"David Nebenzahl" wrote in message
...

So ... how about if a guy were to build some kind of recirculator,
complete
with filtration? Maybe a big (5-10 gal.) tank with some kind of filter
[...]

That's an interesting idea. Before we get too far into this, let's consider
the water first; you do not want softened water for the primary wash.

OK, I'll bite; why? In any case, not an issue, as I don't have softened water.
Just regular stuff (EBMUD, from reservoirs in N. California).


--
"I know I will go to hell, because I pardoned Richard Nixon."

- Former President Gerald Ford to his golf partners, as related by
the late Hunter S. Thompson

"Peter De Smidt" pdesmidt*no*spam*@tds.*net* wrote in message
...
jjs wrote:



That's an interesting idea. Before we get too far into this, let's
consider the water first; you do not want softened water for the primary
wash.

Why not?

Because softened water lacks the minerals that remove hypo/fix. I'm
surprised that people don't know that.

jjs wrote:


Because softened water lacks the minerals that remove hypo/fix. I'm
surprised that people don't know that.



I don't think it's so simple. In fact there's just been a technical
discussion on this on the Pure-Silver mailing list. While it's true
that, for example, sea water will wash photographic materials faster
than demineralized water when a wash aid isn't used, it's not clear that
there's any advantage to using mineralized water after a wash aid.
Morever, softened water isn't de-mineralized. The mineral makeup is
changed to something less likely to cause build up and hard water
stains. I forget the exact details. Finally, it's my experience that
very hard water, like I have here, can cause problems when washing
paper. When I switched to softened water for washing paper, these
problems went away.

-Peter