hypo clear/selenium toner technique
George Huczek
Just a question about technique. After washing, some people use a hypo
clearing agent, in which a selenium toner, of about a 15:1 ratio, is added.
The selenium makes the print more permanent and deepens the black areas.
Why do these two steps simultaneously? It would seem better to first
place the print in a hypo clearing bath, then rewash it, and then put it
into a separate selenium toner bath before a final wash.
Why do experienced darkroom technicians combine the hypo clearing and
selenium mixture in one bath? I hope there is some better reason than
saving the space taken up by an additional processing tray.
--
------George Huczek------
bq...@freenet.carleton.ca
Lou Kipnis
No. The procedure is:
o Fresh Fixer without hardener.
o Kodak Selenium Rapid Toner diluted 1+9 or more, usually ~1+20, with
washing aid (hypo clear, Perma Wash, etc.).
o Water rinse.
o Washing Aid.
o Final Wash.
As I understand the chemistry, wash aid in toning bath acts as buffer
to prevent staining. It does not act as a wash aid, to make fix more
water soluble. Kodak Rapid Selenium Toner contains something like, I
think, 15-20% ammonium thiosulfate (fixer). So, again, wash aid does
not work as wash aid in toner, and prints should be treated in wash
aid and rinse *after* toning. I have toned without wash aid in the
toner with no staining, but use it as standard procedure. [Someone
with more chemistry should be able to give more precise answer as to
action of wash aid in toner, and accurate figure of amount of fix in
selenium toner (too lazy to look it up).]
Toning in fairly dilute selenium toner removes green color present in
most fiber papers, also deepens low values to greater or lesser extent
depending on paper and individual image. Also, it seems generally
agreed that selenium toning aids fiber print longevity as selenium
forms new compound with silver in paper which is resistant to
sulfiding from residual fixer in paper and atmospheric contaminants.
Still, IMO primary reason to selenium tone is aesthetic, removal of
green color and deepening of low values.
Hope this helps,
---
Lou
<lki...@i-2000.com>
___________________________________________________________________
"There's no success like failure, and failure's no success at all."
--Bob Dylan
Guy de Riencourt
>In <DBvww...@freenet.carleton.ca>, bq...@FreeNet.Carleton.CA (George Huczek) writes:
>
>>Just a question about technique. After washing, some people use a hypo
>>clearing agent, in which a selenium toner, of about a 15:1 ratio, is added.
>>The selenium makes the print more permanent and deepens the black areas.
>> Why do these two steps simultaneously? It would seem better to first
>Adding the hypo clearing agent to the selenium toning solution speeds up the
>toning action, and consequently shortens the necessary processing time.
>
>I believe it also serves as a last line of defense against staining.
>
>For more details, check Ansel Adam's The Print for an excellent tutorial
>on technique.
Just a few words on this subject. If you look in the A. Adams book you will find that he says that he always used to dilute the=
Kodak Rapid Selenium Toner with Hypo Clear. He even says that he spoke to Kodak about it and they said that it wouldn't make any di=
fference to dilute with Hypo Clear or Water.
But know if you read Kodak instructions, they recomend using Hypo Clear. It's funny that A. Adams was ahead of Kodaks scientific sta=
ff.
Guy
<deri...@micronet.fr>
Paris, France
John Hessenauer
: ...
: Just a question about technique. After washing, some people use a hypo
: clearing agent, in which a selenium toner, of about a 15:1 ratio, is added.
: The selenium makes the print more permanent and deepens the black areas.
: Why do these two steps simultaneously? It would seem better to first
: into a separate selenium toner bath before a final wash.
: Why do experienced darkroom technicians combine the hypo clearing and
: selenium mixture in one bath? I hope there is some better reason than
: saving the space taken up by an additional processing tray.
: --
: ------George Huczek------
: bq...@freenet.carleton.ca
It is done to eliminate the extra steps of washing. Use the hypo clear
and toner together and then wash. Only 2 steps. Saves time and water
(money!) and gives good results. There is nothing to be gained by the
additional washing step you indicate.
--
John Hessenauer
Hillsborough Community College
The Hawkeye; Photographer
Ybor Connections; Photographer
sfi...@frog.thpl.lib.fl.us
Michael Gudzinowicz
>Just a question about technique. After washing, some people use a hypo
>clearing agent, in which a selenium toner, of about a 15:1 ratio, is added.
>The selenium makes the print more permanent and deepens the black areas.
> Why do these two steps simultaneously? It would seem better to first
>place the print in a hypo clearing bath, then rewash it, and then put it
>into a separate selenium toner bath before a final wash.
> Why do experienced darkroom technicians combine the hypo clearing and
>selenium mixture in one bath? I hope there is some better reason than
>saving the space taken up by an additional processing tray.
hypoclear minimizes rewashing, though an additional plain
hypoclear bath is recommended after toning.
jca...@mindlink.bc.ca
>Just a question about technique. After washing, some people use a hypo
>clearing agent, in which a selenium toner, of about a 15:1 ratio, is added.
>The selenium makes the print more permanent and deepens the black areas.
> Why do these two steps simultaneously? It would seem better to first
>place the print in a hypo clearing bath, then rewash it, and then put it
>into a separate selenium toner bath before a final wash.
> Why do experienced darkroom technicians combine the hypo clearing and
>selenium mixture in one bath? I hope there is some better reason than
>saving the space taken up by an additional processing tray.
Adding the hypo clearing agent to the selenium toning solution speeds up the
toning action, and consequently shortens the necessary processing time.
I believe it also serves as a last line of defense against staining.
For more details, check Ansel Adam's The Print for an excellent tutorial
on technique.
Since I loaned my Second Edition version of The Print to a friend, I'm
referring to the First Edition of The Print I have on hand.
Andrew Cassino
: clearing agent, in which a selenium toner, of about a 15:1 ratio, is added.
: The selenium makes the print more permanent and deepens the black areas.
: Why do these two steps simultaneously? It would seem better to first
: place the print in a hypo clearing bath, then rewash it, and then put it
: into a separate selenium toner bath before a final wash.
: Why do experienced darkroom technicians combine the hypo clearing and
: selenium mixture in one bath? I hope there is some better reason than
: saving the space taken up by an additional processing tray.
As was pointed out in Camera and Darkroom in a recent issue (sorry I
don't recall which one), hypo-clear exhausts *much* faster than
selenium toner, so mixing the two together necessitates using much
more selenium toner than would be needed by keeping the steps
separate. So, it is environmentally prudent to reduce the amount of
very toxic selenium that must be dispensed of by keeping the hypo
clear and toner baths seperate. And, as C&D noted, back when Ansel
Adams used the combined method, selenium was much cheaper than it is
now.
[ Andrew Cassino (and...@lsid.hp.com) ]
[ Phone: 206-335-2211 FAX: 206-335-2340 ]
[ Hewlett-Packard Company ]
[ Lake Stevens Instrument Division ]
[ 8600 Soper Hill Road MS 330 ]
[ Everett, WA 98205-1298 ]
Robert Smith
bq...@FreeNet.Carleton.CA (George Huczek) wrote:
.>Just a question about technique. After washing, some people use a hypo
.>clearing agent, in which a selenium toner, of about a 15:1 ratio, is added.
.>cut<.
.>cut<.
.As I understand the chemistry, wash aid in toning bath acts as buffer
.to prevent staining. It does not act as a wash aid, to make fix more
.water soluble.
YES! It DOES act as a washing aid or hypo clear to neutralize
the effects of hypo.
. Kodak Rapid Selenium Toner contains something like, I
.think, 15-20% ammonium thiosulfate (fixer). So, again, wash aid does
.not work as wash aid in toner, and prints should be treated in wash
.aid and rinse *after* toning. I have toned without wash aid in the
.toner with no staining, but use it as standard procedure. [Someone
.with more chemistry should be able to give more precise answer as to
.action of wash aid in toner, and accurate figure of amount of fix in
.selenium toner (too lazy to look it up).]
.
NO! There is *NO* "fixer" in the selenium toner solution! The
Kodak toner solutions I use have a decided ammonia gas (NH3) odor and
is *VERY* caustic. It is *completely incompatible* with fixer, which
is mildly acidic. Red or orange stains occur on many (Kodak Elite)
fiber papers if the fixer is not totally removed or neutralized with
hypo clear prior to toning. Hypo clear in the toner prevents this.
.Toning in fairly dilute selenium toner removes green color present in
.most fiber papers, also deepens low values to greater or lesser extent
.depending on paper and individual image. Also, it seems generally
.agreed that selenium toning aids fiber print longevity as selenium
.forms new compound with silver in paper which is resistant to
.sulfiding from residual fixer in paper and atmospheric contaminants.
.Still, IMO primary reason to selenium tone is aesthetic, removal of
.green color and deepening of low values.
.cut.
YES! I agree; and tone almost all working prints and all final
prints. Gallerie especially tones well and gives a three-dimentional
quality to the shadow values toward the background. I use the formula
given above but no re-fix or re-hypo clear, but wash, and wash, and
wash.....
dr bob
Barry Sherman
> NO! There is *NO* "fixer" in the selenium toner solution! The
>Kodak toner solutions I use have a decided ammonia gas (NH3) odor and
>is *VERY* caustic. It is *completely incompatible* with fixer, which
>is mildly acidic. Red or orange stains occur on many (Kodak Elite)
>fiber papers if the fixer is not totally removed or neutralized with
>hypo clear prior to toning. Hypo clear in the toner prevents this.
Robert - my experience is diametrically opposed to this statement.
When I started using Kodak Elite, I encountered severe problems with
red-pink-orange staining of my prints. Then I re-read the data
sheet for the paper and noted that it recommended longer fixing times
than other papers. I also discovered, in the back of Carson
Grave's "The Elements of Black and White Printing", a simple formula
for testing for complete fixing of prints: Kodak Rapid Selenium
Toner. The book says that it'll produce red stains when fixing is
inadequate. Hmmmmmm. :-)
When I lengthened my fixing time the problem with staining went
away immediately.
I now fix longer (2-five minute baths of sodium thiosulfate
conventional fixer instead of 2-three minute baths) and go
directly from the 2nd fixer into the Kodak Rapid Selenium toner with
no intermediate rinse and no intermediate Hypo Clearing Agent and
no HCA in the toner and with no problems at all. (I give a *long*
soak in HCA after toning and before washing and adding HCA to
the toner seems superfluous.)
Correspondence with others has shown me that many other go directly
from fixer into toner with no ill effects. But I can instantly
produce red-stained prints by merely shortening my fixing times.
Facts: 1) During the final stages of fixing what's happening
is not removal of undeveloped silver, but conversion of
intermediate fixing by-products into forms which are
more easily water soluble than the initial and
intermediate by-products.
2) Hypo Clearing Agent converts less-soluble fixing
by-products into more water soluble ones.
Hypothesis: What's happening is that the red stains are caused
by a reaction with intermediate fixing compounds which
have not been fully converted into unreactive forms as
they would by longer fixing. A long wash between fix
and toner and/or HCA treatment removes or alters enough
of these compounds to prevent the staining reaction to
occur.
Experiment: Prepare 6 prints as normal. Fix one for 2 minutes
in conventional fixer. Others for 4, 6, 8, 10 and 12
minutes. Now go directly into Kodak Rapid Selenium
Toner. Observe whether there's any difference in
occurance or amount of staining.
I'm going to perform this experiment tonight. Should take no
more than 20-25 minutes. Clearly it will not confirm the hypothesis
that staining is caused by intermediate fixing compounds being present
in the paper, but it *will* confirm or deny my empirical experience
that it's duration of fixing, not intermediate washing, that controls
staining.
I'll report tomorrow what I find.
Barry
--
Barry Sherman, Amdahl Corp. | Dunno which I dislike more: ideologies,
b...@oes.amdahl.com | ideologues or those who follow either.
My opinions, not Amdahl's |
Edward M. Lukacs
incomplete fixing before toning in Hypo Clear/Selenium,
I'd like to introduce a little bit of anarchy!
When I originally tried Ilford's very short fixing-time
archival processing method, the recommended fixing time was
30 seconds with continuous agitation. Ilford later changed
this to 1 minute, as fixing was marginal at 30 seconds.
This gave me an idea. I tried fixing Agfa Portriga 118
this way, using Selenium toner to tell me when fixation
was complete (about 75 seconds). Then I backed off to
a 45 second fix, washed and dried the prints, and waited.
I did not tone the prints, just washed them thoroughly.
The blacks are the usual warm blacks, and the whites are
clean. But the midtones are beautiful tones of mauve,
rather like the tones in old Printing-out paper!
In my senior-level college photo class, it drove my fellow
students crazy! Yes, five years or more later, the prints
are still stable! I think this is because almost but
not quite all the silver bromide was fixed out.
Well, there's my contribution to the science of photographic
printing! Please don't flame me or mail me any bombs!
Instead, as the old Alka-Seltzer commercial said, "Try it...
You'll like it!"
Have fun!
Edward M. Lukacs, LRPS
Miami, FL, USA
Michael Gudzinowicz
> Michael,
>
> I have found that adding 20 grams of sodium
>metabrate per liter of working toner also helps if you go
>directly from fix to toner. It helps neutralize the acid
>carryover from the fix and minimizes staining problems. The
>toner bath itself turns orange when acid carryover is
>excessive.
That's a very good point. With the neutralization of base, one
would see selenious acid in addition to sodium selenite. The
acid is unstable in thiosulfate, and is reduced to selenium,
which often gives red colors depending on environment. Since
this reduction is not related to silver, one might get a
non-specific stain rather than tone (confined to image).
Anyone who wishes to see the effect can take a couple of drops
of EKC Rapid Selenium Toner and add acetic acid... the
solution will turn brilliant red as the selenious acid is
reduced by thiosulfate. Addition of more hypo tends to give
brown-colored crud. If this were to happen in the emulsion,
one would have a very nice stain.
As you probably know, 2% metaborate (Kodalk) is an effective
hypo-clearing agent when paper is soaked in it for 3-5
minutes. Low (1%) concentrations of sodium carbonate has a
similar action, though I avoid carbonate solutions since pH
induced generation of gas bubbles can, and often does, damage
the emulsion. Both compounds remove hardeners and will swell
the emulsion, which should favor toning.
Hypo-clearing agents have been around for over 100 years... in
1889 Bannow used 10% sodium chloride and water washes to
remove hypo, and later it was speculated that excess chloride
anion formed AgCl from residual argentothiosulfate complexes,
and that the AgCl was then removed by chloride, since silver
halides form higher anionic complexes (AgCl2 -1; etc). With a
bit more exploration it was noted that increased pH speeded
hypo removal, and that multivalent anions such as phosphate,
sulfite, and sulfate worked better than the monovalent anions.
Of those agents, 2% sulfite worked very well, but commercial
preps often add some bisulfite to decrease pH and
swelling, and add calcium chelators. One of the suggested
formulations from Haist is: 5g sodium sulfite, 26g sodium
bisulfite and 1g Calgon with WTM 1 liter (pH 5.8).
The composition of commercial preps usually isn't revealed, so
I'd imagine that toner in EKC hypo-clear is different from
others, though most seem to work well.
I usually avoid the controversy and tone after a quick rinse
following the second non-hardening fix and haven't run into
any staining problems.
On the other hand, your approach would seem to be more
reliable. Perhaps using a quick rinse in metaborate prior to
the toner bath might minimize the chance of any staining.
It would appear that the contribution of hypo from the toner
in the toner/hypo-clear mixture would be greater than
carryover. I wonder if this has something to do with the color
shift related to toner dilution, where more concentrated toner
gives warmer colors... perhaps from some intermediate
generated faster at higher concentrations?