fixing fiber paper using hypo

"Jorge Omar" wrote in message
...
Richard

Since papers should be fully developed, I fail to see the
risks of
continuing development in the fixer, and if the fixer is
not acidic, any
alkali carryover shall not do any harm also.

Could you pls comment?

Jorge

Paper is not really fully deveoped. It is _nearly_ fully
developed so if there is much continued developement in the
rinse or fixing bath it can change the density of the print.
I think Ammonium fixer works so quickly that this is
probably not a real issue. Carried over alkali will not hurt
the fixing bath. However, if there is not enough sulfite in
the fixer the developer can produce reaction products which
will leave stains on the print. Also, if there is enough
dissolved silver in the bath the carried over developer will
react with it to produce metallic silver which can cause
dichroic stains on the print.
Where a sulfite wash aid is used alkaline fixers do not
have any advantage in shorter washing times. The sulfite
bath will adjust the gelatin pH to above its isoelectric
point eliminating electronic binding of thiosulfate and
fixer reaction products to the gelatin and image silver. It
will also eliminate the "mordanting" effect of aluminum
sulfate hardener.
Neutral fixing baths are common in color processing. A
water rinse preceding the fixing bath is all that is used
but it is a short running water wash not just a dip in a
tray of re-used water.
The original poster should check to see if Agfa chemistry
is available in his country. If so, Agfa Universal fixer is
a good, neutral pH, non hardening rapid fixer. Actually any
C-41 fixer should do and may be available where B&W
chemistry is hard to find.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Jorge Omar" wrote in message
...
Richard

Since papers should be fully developed, I fail to see the
risks of
continuing development in the fixer, and if the fixer is
not acidic, any
alkali carryover shall not do any harm also.

Could you pls comment?

Jorge

Paper is not really fully deveoped. It is _nearly_ fully
developed so if there is much continued developement in the
rinse or fixing bath it can change the density of the print.
I think Ammonium fixer works so quickly that this is
probably not a real issue. Carried over alkali will not hurt
the fixing bath. However, if there is not enough sulfite in
the fixer the developer can produce reaction products which
will leave stains on the print. Also, if there is enough
dissolved silver in the bath the carried over developer will
react with it to produce metallic silver which can cause
dichroic stains on the print.
Where a sulfite wash aid is used alkaline fixers do not
have any advantage in shorter washing times. The sulfite
bath will adjust the gelatin pH to above its isoelectric
point eliminating electronic binding of thiosulfate and
fixer reaction products to the gelatin and image silver. It
will also eliminate the "mordanting" effect of aluminum
sulfate hardener.
Neutral fixing baths are common in color processing. A
water rinse preceding the fixing bath is all that is used
but it is a short running water wash not just a dip in a
tray of re-used water.
The original poster should check to see if Agfa chemistry
is available in his country. If so, Agfa Universal fixer is
a good, neutral pH, non hardening rapid fixer. Actually any
C-41 fixer should do and may be available where B&W
chemistry is hard to find.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Dan Quinn" wrote in message
om...
(sreenath) wrote

If I don't want the hardner...


Then all you need is sodium thiosulfate. In your shoes
I'd add
a small portion of sulfite or bisulfite for better
keeping.
I use S. or A. Thio. one-shot, very dilute; always
fresh. Two
baths for archival results.
Dan


"Richard Knoppow" wrote
Sodium thiosulfate fixer does a good job.


About 5 grams of sulfite per liter is enough to preserve
the thiosulfate (either kind) but increasing it to about 15
grams will add a safety factor to take care of the reaction
products of carried over developer. Sulfite will give you a
nearly neutral bath, bisulfite a slightly acid one.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Dan Quinn" wrote in message
om...
(sreenath) wrote

If I don't want the hardner...


Then all you need is sodium thiosulfate. In your shoes
I'd add
a small portion of sulfite or bisulfite for better
keeping.
I use S. or A. Thio. one-shot, very dilute; always
fresh. Two
baths for archival results.
Dan


"Richard Knoppow" wrote
Sodium thiosulfate fixer does a good job.


About 5 grams of sulfite per liter is enough to preserve
the thiosulfate (either kind) but increasing it to about 15
grams will add a safety factor to take care of the reaction
products of carried over developer. Sulfite will give you a
nearly neutral bath, bisulfite a slightly acid one.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Tom" tom@localhost wrote in message
...
Why in the heck would you need two baths when using it
one-shot? Two bath hypo
systems are used as protection against used up hypo. The
only way one-shot hypo
is going to get used up is if you made it too dilute.
There is either enough
hypo in it, or there is not. Your statement seems silly on
the face of it.

--

Dan Quinn wrote:

(sreenath) wrote

If I don't want the hardner...



Then all you need is sodium thiosulfate. In your shoes
I'd add
a small portion of sulfite or bisulfite for better
keeping.
I use S. or A. Thio. one-shot, very dilute; always
fresh. Two
baths for archival results.
Dan



"Richard Knoppow" wrote

Sodium thiosulfate fixer does a good job.

You should not need two baths for one-shot fixing. I
also worry about the "very dilute" fixer. Fixer depends on
having a lot of free thiosulfate ions available. As it works
the thiosulfate bonds the silver. It takes about three
thiosulfate ions to convert one ion of silver halide. A very
dilute bath may become exhausted to the point of not being
able to complete the fixing process before even a single
film or paper is fixed. Two baths might work better here.
However, since a two bath system has a very large capacity
for archival fixing when compared to a single bath it is
probably more economical than using fixer one shot. Ammonium
thiosulfate has much larger capacity than sodium thiosulfate
especially for film. It is much less affected by Iodides
from the film and generally by the amount of dissolved
silver.
There is a tendency for Ammonium Thiosulfate fixer (Rapid
fixer) to dissolve metallic silver, bleaching the image,
when film or paper is left in it too long but this effect
takes place only when the fixer is acid, so is not a problem
with neutral or alkaline rapid fixers.


--
---
Richard Knoppow
Los Angeles, CA, USA

"Tom" tom@localhost wrote in message
...
Why in the heck would you need two baths when using it
one-shot? Two bath hypo
systems are used as protection against used up hypo. The
only way one-shot hypo
is going to get used up is if you made it too dilute.
There is either enough
hypo in it, or there is not. Your statement seems silly on
the face of it.

--

Dan Quinn wrote:

(sreenath) wrote

If I don't want the hardner...



Then all you need is sodium thiosulfate. In your shoes
I'd add
a small portion of sulfite or bisulfite for better
keeping.
I use S. or A. Thio. one-shot, very dilute; always
fresh. Two
baths for archival results.
Dan



"Richard Knoppow" wrote

Sodium thiosulfate fixer does a good job.

You should not need two baths for one-shot fixing. I
also worry about the "very dilute" fixer. Fixer depends on
having a lot of free thiosulfate ions available. As it works
the thiosulfate bonds the silver. It takes about three
thiosulfate ions to convert one ion of silver halide. A very
dilute bath may become exhausted to the point of not being
able to complete the fixing process before even a single
film or paper is fixed. Two baths might work better here.
However, since a two bath system has a very large capacity
for archival fixing when compared to a single bath it is
probably more economical than using fixer one shot. Ammonium
thiosulfate has much larger capacity than sodium thiosulfate
especially for film. It is much less affected by Iodides
from the film and generally by the amount of dissolved
silver.
There is a tendency for Ammonium Thiosulfate fixer (Rapid
fixer) to dissolve metallic silver, bleaching the image,
when film or paper is left in it too long but this effect
takes place only when the fixer is acid, so is not a problem
with neutral or alkaline rapid fixers.


--
---
Richard Knoppow
Los Angeles, CA, USA

On 20 Jul 2004 22:28:58 -0700,
(sreenath) wrote:

Thanks for the information.
I have been using sodium bisulfite stop bath for both film and paper.
If I can get away without a stop bath, at least for paper, one less
thing to deal with!

-Sreenath

Jorge Omar wrote in message . 4...
I use a formula very much similar to yours non hardening, and a water
stop bath (I place papers in about 2L of water for some 30s with
agitation).

This way, acetic acid or the like is not necessary.


jul2404 from Lloyd Erlick,

I've been using a plain tap water bath in place of an acid
stop bath for a long time now. I do it for both film and
paper. My method might seem somewhat extreme, because I use
four changes of water, but it works well for me. It removes
a lot of the developer rather than merely causing the
developer's environment to be acidic.

In fact, I agree with you that acetic acid, or any acid, is
not necessary for the usual darkroom processes of black and
white film and paper. I've eliminated it from my fixer, too,
and use no acid in my darkroom. Darkroom odor is now gone.
And my selenium toner solution stays clear instead of
forming that dark precipitate.

regards,
--le
________________________________
Lloyd Erlick Portraits, Toronto.
voice: 416-686-0326
email:
net: www.heylloyd.com
________________________________

On 20 Jul 2004 22:28:58 -0700,
(sreenath) wrote:

Thanks for the information.
I have been using sodium bisulfite stop bath for both film and paper.
If I can get away without a stop bath, at least for paper, one less
thing to deal with!

-Sreenath

Jorge Omar wrote in message . 4...
I use a formula very much similar to yours non hardening, and a water
stop bath (I place papers in about 2L of water for some 30s with
agitation).

This way, acetic acid or the like is not necessary.


jul2404 from Lloyd Erlick,

I've been using a plain tap water bath in place of an acid
stop bath for a long time now. I do it for both film and
paper. My method might seem somewhat extreme, because I use
four changes of water, but it works well for me. It removes
a lot of the developer rather than merely causing the
developer's environment to be acidic.

In fact, I agree with you that acetic acid, or any acid, is
not necessary for the usual darkroom processes of black and
white film and paper. I've eliminated it from my fixer, too,
and use no acid in my darkroom. Darkroom odor is now gone.
And my selenium toner solution stays clear instead of
forming that dark precipitate.

regards,
--le
________________________________
Lloyd Erlick Portraits, Toronto.
voice: 416-686-0326
email:
net: www.heylloyd.com
________________________________

On Wed, 21 Jul 2004 00:47:30 -0700, "Richard Knoppow"
wrote:


"sreenath" wrote in message
. com...
I can get Ammonium chloride easily. I see from newsgroup
postings that
the formula for F-7 fixer is :

Water, about 1250F (500C) 600 ml
Sodium thiosulfate pentahydrate 360 g
Ammonium chloride 50 g
Sodium sulfite, desiccated 15 g
Acetic acid, 28% 48 ml
Boric acid, crystals 7.5 g
Potassium alum 15 g
Cold water to make 1.0 liter

If I don't want the hardner, will the following formula
do?

(Non hardening version of Kodak Rapid Fixing Bath F-7)

Water, about 1250F (500C) 600 ml
Sodium thiosulfate pentahydrate 360 g
Ammonium chloride 50 g
Sodium sulfite, desiccated 15 g
Cold water to make 1.0 liter

Is acetic acid necessary? Could sodium bisulfite be used
as an
alternative to Acetic acid?

Is the temperature of water right? I have always used
water without
heating, but the formula above specifies 125 degree
Farenheit.

Thanks for the help,
Sreenath


The above should be work fine.
Previous stuff snipped... Any hadening fixer can be made
non-hardening by leaving out the hardener. Since the acid is
there mainly for the hardener it can also be left out. Both
Ammonium and Sodium Thiosulfate work regardless of pH.
Fixer with Ammonium chloride and Sodium thiosulfate is
faster than Sodium thiosulfate but not quite as fast as when
made with Ammonium thiosulfate.

Please accomodate me here, Richard. When reading the following
entence, I was a bit confused as to your meaning.
..
Note that when neutral or alkaline Ammonium thiosulfate
fixers no longer bleach the image.

Did you leave out comma? If you meant:

" Note that when neutral or alkaline, Ammonium thiosulfate
^
fixers no longer bleach the image."

then I assume the next sentence refers to the situation applying to
the use of AT fixers in the usual Acid state. Is that what you meant?

This is not usually a
problem when fixing times are not extended but can affect
warm tone paper especially if the paper is left in the fixer
longer than necessary for fixing.

Regards


Robert Vervoordt, MFA

On Wed, 21 Jul 2004 00:47:30 -0700, "Richard Knoppow"
wrote:


"sreenath" wrote in message
. com...
I can get Ammonium chloride easily. I see from newsgroup
postings that
the formula for F-7 fixer is :

Water, about 1250F (500C) 600 ml
Sodium thiosulfate pentahydrate 360 g
Ammonium chloride 50 g
Sodium sulfite, desiccated 15 g
Acetic acid, 28% 48 ml
Boric acid, crystals 7.5 g
Potassium alum 15 g
Cold water to make 1.0 liter

If I don't want the hardner, will the following formula
do?

(Non hardening version of Kodak Rapid Fixing Bath F-7)

Water, about 1250F (500C) 600 ml
Sodium thiosulfate pentahydrate 360 g
Ammonium chloride 50 g
Sodium sulfite, desiccated 15 g
Cold water to make 1.0 liter

Is acetic acid necessary? Could sodium bisulfite be used
as an
alternative to Acetic acid?

Is the temperature of water right? I have always used
water without
heating, but the formula above specifies 125 degree
Farenheit.

Thanks for the help,
Sreenath


The above should be work fine.
Previous stuff snipped... Any hadening fixer can be made
non-hardening by leaving out the hardener. Since the acid is
there mainly for the hardener it can also be left out. Both
Ammonium and Sodium Thiosulfate work regardless of pH.
Fixer with Ammonium chloride and Sodium thiosulfate is
faster than Sodium thiosulfate but not quite as fast as when
made with Ammonium thiosulfate.

Please accomodate me here, Richard. When reading the following
entence, I was a bit confused as to your meaning.
..
Note that when neutral or alkaline Ammonium thiosulfate
fixers no longer bleach the image.

Did you leave out comma? If you meant:

" Note that when neutral or alkaline, Ammonium thiosulfate
^
fixers no longer bleach the image."

then I assume the next sentence refers to the situation applying to
the use of AT fixers in the usual Acid state. Is that what you meant?

This is not usually a
problem when fixing times are not extended but can affect
warm tone paper especially if the paper is left in the fixer
longer than necessary for fixing.

Regards


Robert Vervoordt, MFA