HELP! Yellow stains on prints
Ian Dodd
that are displaying yellow stains all around the edges. I can’t figure out
where this contamination has come from.
I put the paper through fresh developer for two minutes, 30 seconds in the stop
bath and one minute in a “rapid” (ammonia thiosulphate) fixer bath. The prints
then went to a holding tray of hypo clear where, after I finished printing, I
gave them all a 5 minute wash, toned them in selenium (1:19 for 9 minutes), and
put them in the print washer for 20 minutes. Nothing new or different from
what I always do.
An hour or so after putting them out to dry, I walked through the room and
noticed bright yellow stains around the edges of the prints. There are no
distinct marks, like fingerprints from contaminated hands. And why just around
the edges?
Fortunately, they were just test prints of a step wedge (see my earlier post on
calibrating my paper `a la Steve Anchell’s “Variable Contrast Printing
Manual”), so nothing critical. But I hesitate to spend a lot of time coaxing a
decent image out of some new negatives if I’ve got a problem somewhere.
I need one of the photo chemists on this newsgroup to help me solve this
mystery. Seems like I’ve probably gotten something cross-polinated, but I have
no idea what. Can you guys help? Sorry for all the laborious detail, but I
figure there's a clue there somewhere. Thanks in advance.
Ian
SPECTRUM
with Hypo-Check or simply replace it with a new bath.
The yellowing might be residual argento-thiosulfate
complexes or just plain residual undeveloped halides that
weren't removed.
Did you notice any flattening of the image tones ?
If so then your fix is really shot. Leaving residual silver
in the print which would darken slightly when exposed to
light for a while.
Regards,
-----------------------------------------------------------------
John S. Douglas
Spectrum Photographic Inc. - http://www.spectrumphoto.com
Website: Portraiture, Wedding Photography, Darkroom Tech.,
World Field Photographers Association, FAQ's & More!
-----------------------------------------------------------------
On 2 Aug 1998 04:52:03 GMT, ian...@aol.com (Ian Dodd)
wrote:
Richard Knoppow
I also suspect under fixing but don't understand the border effect.
Selenium toner is used as a test for adequate fixing as an alternative
to Sodium Sulfide. If there is any unfixed halide it will stain brown
or yellow. This stain takes some minutes to appear and will continue
to darken for a time. It may be that the fixing time is too short.
You can test this by extending the fixing time. Some fiber papers will
not fix in one minute even in film-strength fixer. Try fixing for four
minutes, which should be plenty for film strength rapid fixer and try
again. If you are using the fixer at paper strength it will need at
least four to six minutes to fix out fiber paper. At that strength
the fixing time is about the same as conventional fixer.
Test this first, it still could be somthing else.
BTW, if you are using trays which are only slightly larger than the
prints the "border" may be the result of lessened agitation near the
edges.
Also, try using a regimen for fixing of a first bath folowed by plain
water holding bath (running water) followed by a mass second fixing
when you are finished. Follow that with the wash aid and washing. The
wash aid being used as a holding bath may be becomming saturated with
hypo. If this bath is not agitated much that may also explain the
"border". The second fix and final wash aid also gives all the
prints a uniform treatment before washing.
Please let us know if any of this advise is helpful.
---
Richard Knoppow
Los Angeles, Ca.
dick...@ix.netcom.com
Lloyd Erlick
>I’ve got a batch of B&W fiber-based prints on the drying screens right now
>that are displaying yellow stains all around the edges. I can’t figure out
>where this contamination has come from.
>I put the paper through fresh developer for two minutes, 30 seconds in the stop
>bath and one minute in a “rapid” (ammonia thiosulphate) fixer bath. The prints
>then went to a holding tray of hypo clear where, after I finished printing, I
>gave them all a 5 minute wash, toned them in selenium (1:19 for 9 minutes), and
>put them in the print washer for 20 minutes. Nothing new or different from
>what I always do.
>An hour or so after putting them out to dry, I walked through the room and
>noticed bright yellow stains around the edges of the prints. There are no
>distinct marks, like fingerprints from contaminated hands. And why just around
>the edges?
>Fortunately, they were just test prints of a step wedge (see my earlier post on
>calibrating my paper `a la Steve Anchell’s “Variable Contrast Printing
>Manual”), so nothing critical. But I hesitate to spend a lot of time coaxing a
>decent image out of some new negatives if I’ve got a problem somewhere.
>I need one of the photo chemists on this newsgroup to help me solve this
>mystery. Seems like I’ve probably gotten something cross-polinated, but I have
>no idea what. Can you guys help? Sorry for all the laborious detail, but I
>figure there's a clue there somewhere. Thanks in advance.
>Ian
aug298 from Lloyd Erlick,
This sounds like the old traditional
too-much-acid-transferring-into-the-selenium-toner problem. My memory
of those yellow stains (bright yellow in my case) is that they are
caused by failure to remove or neutralize the acid from stop bath
and/or fixer before the print goes into the selenium toner. If a
holding bath is being used it could be building up too much acid from
the prints stored in it. Try dumping and replacing with plain water
frequently during the session.
Ansel Adams in 'The Print' recommends a 'plain fixer' for use as
second fixing bath in two-bath setups. He says to use toner
immediately after this fix, no rinse in between. Otherwise a rinse can
be applied after an ordinary acid fixer, followed by a mild alkaline
bath such as Kodalk 2% (expensive) or sodium sulfite 2% (cheap), then
the selenium toner.
I have adopted Adams' plain fix (cheap and odorless) for both my
fixing baths. I rinse the print thoroughly after the developer step
(developer carry-over to fix is one more potential cause of stains)
then stop in citric acid, 15 grams per liter (no smell), then another
thorough rinse to prevent acid-carry-over to the fix and toner. The
print goes from first fix to second and on to selenium toner with no
further rinses. It is thoroughly rinsed after the toner and then on to
two baths of sodium sulfite 2% as hypo clear. I find no yellow stains
with this method.
--le
~~~~~~~~~~~~~~~~~~~~~~~~~
Lloyd Erlick,
357 Richmond Street West,
Toronto M5V 1X3 Canada,
---
voice416-596-8751,
ll...@the-wire.com,
http://www.heylloyd.com
~~~~~~~~~~~~~~~~~~~~~~~~~
Michael A. Covington
>Ian Dodd wrote:
>> I?ve got a batch of B&W fiber-based prints on the drying screens right
now
>> that are displaying yellow stains all around the edges. I can?t figure
out
>> where this contamination has come from.
>> I put the paper through fresh developer for two minutes, 30 seconds in
the stop
>
>This sounds too short for a rapid fixer for single bath paper fixer. Kodak,
for
>example, recommend 10 minutes for Elite paper. They recommend 5-10 minutes
for
>paper-strength rapid fixer. ..
I think you've put your finger on it... he is using the fixing time for RC
paper. The fixing time for fiber-base paper is considerably longer. BTW,
can someone explain why this is? The emulsion is presumably the same; does
the fiber base interfere with fixation somehow?
Jean-David Beyer
> I?ve got a batch of B&W fiber-based prints on the drying screens right now
> that are displaying yellow stains all around the edges. I can?t figure out
> where this contamination has come from.
>
> I put the paper through fresh developer for two minutes, 30 seconds in the stop
> bath and one minute in a ?rapid? (ammonia thiosulphate) fixer bath.
This sounds too short for a rapid fixer for single bath paper fixer. Kodak, for
example, recommend 10 minutes for Elite paper. They recommend 5-10 minutes for
paper-strength rapid fixer. (Did you give constant agitation?) You might get away
with several minutes in film-strength rapid fixer, but you certainly need to test
this before committing any serious work to the procedure.
In fact, putting selenium toner on the white areas of a print for 2 to 3 minutes
and examining the stain is one of the tests for proper fixation. It sounds as
though you have done this test and failed.
> The prints
> then went to a holding tray of hypo clear where, after I finished printing, I
> gave them all a 5 minute wash, toned them in selenium (1:19 for 9 minutes), and
> put them in the print washer for 20 minutes. Nothing new or different from
> what I always do.
>
> An hour or so after putting them out to dry, I walked through the room and
> noticed bright yellow stains around the edges of the prints. There are no
> distinct marks, like fingerprints from contaminated hands. And why just around
> the edges?
Perhaps inadequate agitation resulted in poorer fixing at the edges. In any case,
were you to give sufficient fixing, you probably would not have had the problem.
--
Jean-David Beyer
Shrewsbury, New Jersey
Tim Shoppa
Michael A. Covington <covi...@mindspring.com> wrote:
>I think you've put your finger on it... he is using the fixing time for RC
>paper. The fixing time for fiber-base paper is considerably longer. BTW,
>can someone explain why this is? The emulsion is presumably the same; does
>the fiber base interfere with fixation somehow?
Everything seems to take several times longer with fiber-base papers. For
example, with RC papers in fresh developer, I usually see what
appears to be a fully-developed image in 5-10 seconds. With
the fiber-based papers that I use it's more like 15-20 seconds to
see the first hint of an image and the density is still visibly
increasing at 45-50 seconds.
I'm pretty sure the RC papers I use (Ilford MG IV Deluxe and Kodak Polymax)
aren't developer incorporated, though I could be mistaken. Don't
the developer-incorporated types usually say "Rapid" or something
similar?
My interpretation of the shorter processing times with RC papers is
that the gelatin emulsion is substantially different than for FB papers.
I certainly have scratched the image on FB papers during processing,
while I don't think this has ever happened with RC papers.
Tim.
SPECTRUM
Shoppa) wrote:
>I'm pretty sure the RC papers I use (Ilford MG IV Deluxe and Kodak Polymax)
>aren't developer incorporated, though I could be mistaken. Don't
>the developer-incorporated types usually say "Rapid" or something
>similar?
Actually both of those papers have a small amount of
developer incorporated in them. From what I've been told
that's the tack that most manufacturers are taking today.
Don't know for sure about Agfa's RC though.