Pink cast on Tri-X?

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

glaserp@sustainsoft.com - 17 May 2005 01:11 GMT

Hi,

>From what I've read, the signs of insufficient fixing for TMAX is a

pinkish cast whereas for traditional, non tabular grain films, it would
be a "milky" appearance. This evening I just developed my first roll of
tri-x in a long time. It is from a bulk roll of 100'. I fixed for 5
minutes in Kodafix, tested the fixer for exhaustion, and examined the
negatives looking for the milky appearance and didn't see anything
looking amiss. I rinsed, washed in permawash, and rinsed again. Now
that my film is dry, it appears to have a pink cast to it. It's hard to
see the cast in daylight, but if I hold the film against white paper
and shine a compact-fluosrescent light on it, it looks downright pink.

What is going on here? Does the new tri-x behave like TMAX in this
regard?

Also, assuming I have indeed under fixed or or under washed, is there
anything I can or should do to preserve the negatives? I was looking at
this roll as being a test (it's radically under exposed) but it turns
out to have a few decent shots and I'd hate to have anything bad happen
to them.

Thanks.

--Phil

Reply to this Message

dr bob - 17 May 2005 12:50 GMT

> Hi,
>
[quoted text clipped - 21 lines]
>
> --Phil

First, your film is probably OK as is. If you want to get every last bit of
color from the film, just rewash in a good HCA and then water. I soak mine
for a while in a couple of water changes and that has always removed the
color.

This "problem" comes up here very often and it has been explained often.
Here goes again: the residual color seen in many Kodak B&W films is due to
a sensitizing dye. It is not the anti-halation dye as is sometimes
reported. That dye is removes completely in the developer. I did some
tests in the past to affirm this. It is true that poor fixing can leave a
bunch of color but that is because the film has not been in contact with
water portion of the fixer and not the fixing chemicals per se.

I have had great success just allowing the film to reside in a water bath,
changed frequently after treatment in HCL. No deleterious effect should
occur even if you don't get all the color out. Any milky-ness will require
re-fixing to remove completely for archival purposes.

Truly, dr bob.

Reply to this Message

glaserp@sustainsoft.com - 17 May 2005 14:08 GMT

> This "problem" comes up here very often and it has been explained often.
> Here goes again:

I did do a search but must have missed the previous posts (probably
because it was late at night and I was feeling so perplexed and
dismayed [even had trouble sleeping]; I mean, it's not every day (I
hope) that your film goes pink!). Thanks for your forebearance.

> the residual color seen in many Kodak B&W films is due to
> a sensitizing dye. It is not the anti-halation dye as is sometimes
[quoted text clipped - 7 lines]
> occur even if you don't get all the color out. Any milky-ness will require
> re-fixing to remove completely for archival purposes.

Just to clarify: you are saying that it is it _still_ true that the
indication of insufficient fixing (i.e., left-over undeveloped silver
halide ) for T-grain films is different than for traditional films
(pinkish cast versus milky-ness, respectively), hence your reassurance
that my film is ok?

The remaining quandry for me, then, is why my process is sufficient to
remove the dye in TMAX but not in TRI-X? I did everything _exactly_ the
same except for, as per Kodak's recommendation, fixing the tmax for a
few minutes longer (seven minutes as opposed to five for tri-x).

Is it that TMAX doesn't have the dye? And, if the dye isn't for
anti-halation, what is it's purpose?

Thanks again for your help!

--Phil

Reply to this Message

Bernie - 21 May 2005 02:42 GMT

Phil, there are many misunderstandings about the pink cast in Tmax and other
films. This is NOT an antihalation dye. It is a sensitizing dye, coated on
the silver halide crystals to make them sensitive to specific wavelengths of
light.

Some washes out in the developer, but most washes off in fixer due to the
sulfite which is a kind of solvent for the dye. This is why treatment in
Hypoclearing agent does a good job of removing the dye. While not comon in
Tri-X, the same dye is sometimes seen.

As far as the cloudy hazy look from under-fixing mentioned earlier, that is
caused by incomplete fixing not removing all the undeveloped silver halide
from the emulsion. This has nothing in common with the pink sensitizing dye
being retained.

Also, any pink dye will eventually fade if the film is exposed to light,
such as being left on a light table for several hours.

> The remaining quandry for me, then, is why my process is sufficient to
> remove the dye in TMAX but not in TRI-X? I did everything _exactly_ the
[quoted text clipped - 7 lines]
>
> --Phil

Reply to this Message

Richard Knoppow - 22 May 2005 00:41 GMT

>> This "problem" comes up here very often and it has been
>> explained
[quoted text clipped - 62 lines]
>
> --Phil

I seem to have missed the orignal post, I assume the
question is yours.
Tri-X should not have the residual sensitizing dye problem
that T-Max and Delta films have. A pinkish cast is from
incomplete fixing, it is residual halide, not dye although
there may some sensitizing dye there too. Tri-X is slow to
fix, as slow as T-Max. Even though it is a conventional
cubic crystal emulsion it contains a lot of Silver Iodide.
Iodide tends to act as a restrainer on fixing. It has much
less effect on Ammonium thiosulfate (rapid) fixer than on
Sodium thiosulfage fixer. While either will completely fix
either film the time needed for Sodium thiosulfate fixer is
considerably extended. I strongly advise using a two-bath
system with either type of fixer to insure complete fixing
followed up with a treatment in a sulfite wash aid like
Kodak Hypo Clearing Agent.
Refix the Tri-X, preferably in _fresh_ rapid fixer. You
should be able to see the stain disappear. Once it goes
continue fixing for about the same amount of time. The treat
in KHCA and wash.
Check fixers when they are freshly mixed by making a clip
test for clearing time. The clip should be of whatever film
you are going to use. If more than one kind, test all. Soak
the film for a few minutes in plain water, then fix in a
sample of the fixer and not the time it takes for the film
to become clear. Fixing time should be double this at the
start. Re-check the time occasionally. This is a better test
than the Potassium iodide test because it is a direct
measure of the activity of the fixing bath. The reason for
the brief soak in water is that the fixing rate of dry film
is different than wet film.
The capacity of a single fixing bath for complete
(archival) fixing is very limited. For film, rapid fixer has
a considerably greater capacity but for reliable fixing and
economy a two bath system should be used. For sodium
thiosulfate baths a two bath system has 4 to 10 times the
capacity of a single bath. Because a sulfite wash aid makes
some otherwise insoluble fixer reaction products soluble it
has the effect of increasing the capacity of the fixer even
more. It is the insoluble products left in the emulsion
which will eventually attack and destroy the image.
Film can be refixed to clear it for a very long time but
after about two weeks the residue in the film begings to
change to a form which can no longer be completely removed
by refixing so such negatives may have limited life even if
properly refixed. Fixer is cheap, bad fixing ruins
negatives, it is false economy to try to extend it.
BTW good agitation is as necessary for good fixing as for
development. More or less constant agitation is best but
frequent intermittant agitation is satisfactory.

Signature

---
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com

Reply to this Message

glaserp@sustainsoft.com - 22 May 2005 15:19 GMT

Hi Richard,

As always I am grateful for your patience in taking the time to explain
the inner workings of what are, to me, the rather mysterious inner
workings of film processing.

This pink residue episode is deeply troubling to me. I am now resolved
to to switch to a two-bath fixing process and two rigourously test my
fixer for the film I'm using.

I need to get clarification on a few points about fixing and washing.

First, as for the film clip test, is the idea to use an unexposed,
undeveloped piece of the film. So for example I can just cut off a
piece of leader before I develop? And then what I am testing is the
amount of time it takes for the film to become clear?

Second, for agitation during fixing, is it adequate to agitate
constantly for the first 30 seconds, and then agitate for two
inversions every 30 seconds thereafter?

Third, several years ago
(http://groups-beta.google.com/group/rec.photo.darkroom/msg/2dd6689b655c2be0?hl=en)
you suggested that washing in statnding water is acceptable as follows:
after treatment in KHCA, soak the film in 4-5 fresh water baths of two
minutes each. I've been using this method for a while now but just read
in Anchell and Tropp (p. 107) that this method should only be used for
non-hardening fixers (I'm using Kodafix). Do you agree with this? Do
you have any other comments about this?

Fourth, according to the package, KHCA stock solution is supposed to
last for three months in a full container. Is this conservative? is
there any way to test KHCA? And how long will it keep in a _unfull_
container?

Finally, can I use the clip-test to determine when to discard fixing
bath no. 1. I assume that, as the fixer becomes saturated, the amount
of time it takes to clear increases . Can we say that, after an
increase of clearing time by a given factor, it is time to discard the
fixer?

Thanks again for your help!

--Phil

Reply to this Message

UC - 23 May 2005 03:54 GMT

This is way too complicated.

1) Use FRSH Rapid Fixer (I use Kodak)
2) Fix for 5 minutes
3) Wash, then use TWO cycles of Perma-Wash

I have NO pink residue.

> Hi Richard,
>
[quoted text clipped - 18 lines]
>
> Third, several years ago

(http://groups-beta.google.com/group/rec.photo.darkroom/msg/2dd6689b655c2be0?hl=en)

> you suggested that washing in statnding water is acceptable as follows:
> after treatment in KHCA, soak the film in 4-5 fresh water baths of two
[quoted text clipped - 17 lines]
>
> --Phil

Reply to this Message

Lloyd Erlick - 23 May 2005 18:09 GMT

...

>Second, for agitation during fixing, is it adequate to agitate
>constantly for the first 30 seconds, and then agitate for two
>inversions every 30 seconds thereafter?

...

may2305 from Lloyd Erlick,

In my opinion, Tri-X should be fixed in the
same manner as the T-Max films. Constant
agitation during the fix step is best. It
doesn't need to be vigourous - I set my tank
on its side in the sink and roll it slowly
back and forth. I never leave it still for
more than a few seconds because some parts of
the films might be out of the solution when
the tank is on its side. I also stand the
tank up and put it down again frequently.
Fixing is just as important as developing,
and it deserves one's attention.

I think it's a very good decision to use a
double-bath setup for fixing Tri-X and other
film. I never bother to promote my second fix
to first position. I just discard both and
make fresh ones. I use the 'simple fixer'
described by Ansel Adams in "The Print",
which is so cheap to prepare that keeping a
partially used fix is unnecessary.

regards,
--le

Signature

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

Reply to this Message

Richard Knoppow - 29 May 2005 09:04 GMT

> Hi Richard,
>
[quoted text clipped - 20 lines]
> testing is the
> amount of time it takes for the film to become clear.

Thats it but see my note below about soaking. Wet film
fixes out faster than dry film.
The rule of thumb is to fix for twice the time it takes to
clear the film. Somewhat longer fixing doesn't hurt
anything.

> Second, for agitation during fixing, is it adequate to
> agitate
> constantly for the first 30 seconds, and then agitate for
> two
> inversions every 30 seconds thereafter?

I just did some clip tests and found that the film seemed
to take a very long time to clear compared to film that had
been developed. I think I didn't soak it for long enough.
Two or three minutes is probably not enough, try five
minutes or even more. Then fix and see how long it takes to
clear.
You can't over agitate fixing. Fixing will be fastest for
continuous agitation but its not necessary. In tanks I give
it a long series of inversions a couple of times a minute.
Its a process that goes through completion, unlike
development, so as are as agitation the more the better.

> Third, several years ago
> (http://groups-beta.google.com/group/rec.photo.darkroom/msg/2dd6689b655c2be0?hl=en)
[quoted text clipped - 17 lines]
> _unfull_
> container?

Kodak is usually pretty conservative in its shelf life
specs. However, there is no simple way to tell when the KHCA
is no longer good. What happens is that the Sulfite slowly
oxidizes to Sulphate. While sulphate does no harm it does
not have the ion exchange property of Sulfite. KHCA does not
turn color like developer or develop an odor so one must
just discard it after a reasonable time.

> Finally, can I use the clip-test to determine when to
> discard fixing
[quoted text clipped - 5 lines]
> discard the
> fixer?

That's it. The old rule of thumb is to discard the fixer
when clearing time doubles. This is far beyond the point
where a single bath is not longer fixing completely, that is
to the point where no complexes are left in the emulsion
after washing. In a two bath system the first bath can
tollerate a much greater amount of dissolved silver since it
does not have to complete the fixing. That is done by the
second bath, which remains relatively free of dissolved
silver because most of it comes out in the first bath.
Therefore it will have anough free thiosulfate ions
available to convert the remaining silver complexes into a
soluble form.
The iodide test is quite usable providing one knows the
concentration of iodide. The sensitivty of the test varies
with the iodide concentration. Thats why I am scpetical of
the made up test baths, simply, I have no idea of their
concentration or how much dissolved silver they are intended
to show up. The test solution is easy to make up. Here is
Kodak's test:

Kodak Fixer Test Solution FT-1
Water, at 80F or 27C 750.0 ml
Potassium Iodide 190.0 grams
Water to make 1.0 liter

To test a single bath or the first bath of a two bath system
take 5 drops of test solution and add 5 drops of fixer and 5
drops of water. Discard the fixing bath is a yellow-white
precipitate forms instantly.
This is a life-time supply, If you make it up 50ml or
100ml is a more practical amount.

> Thanks again for your help!
>
> --Phil

Signature

---
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com

Reply to this Message

dan.c.quinn@att.net - 17 May 2005 23:27 GMT

> ...the residual color seen in many Kodak B&W films
> is due to a sensitizing dye.

That 'pink' is not unique to Kodak films. While testing
for minimal thiosulfate levels for complete fixation I produced
two rolls of pink Pan F+.
Likely the tendency to hold a color cast varies from film to
film. The T films seem to be most prone. One of these days I'll
test a T with the very dilute one-shot fix I use. I think, perhaps,
the T films are more sensitive to the fixer's silver level. We both
know how sensitive can be some color indicators in detecting minute
amounts of some element. That 'pink' is an indication.
I'll mention once again the solubility of the sodium and ammonium
silver thiosulfate complexes. Some other elements, as impurities in
complex, may not be the least bit soluable. Their presence in
minute amounts may hold silver and it's sensitizer in the
emulsion. Silver levels and/or impurities are suspect
Test using distilled water in enough volume for one roll with
S. or A. thiosulfate sufficient to fix a roll. Dan

Reply to this Message

Jan T - 20 May 2005 22:27 GMT

dr bob,

I assume you meant the anti-halo is solved in the fixing bath?
I agree that the pinkish/pruple colour of the film is removed by washing -
plain water is enough in my experience.

Jan

| <glaserp@sustainsoft.com> wrote in message
| Here goes again: the residual color seen in many Kodak B&W films is due to
[quoted text clipped - 10 lines]
|
| Truly, dr bob.

Reply to this Message

dr bob - 21 May 2005 14:24 GMT

> dr bob,
>
[quoted text clipped - 3 lines]
>
> Jan

Antihalation dyes are "normally" removed or decolorized in the developer.
Some can be dissolved in a pre-rinse. Sometime check this out. TMax and
EFKE films return a deep blue-purple solution when pre-washed. That is the
antihlation dye(s). The sensitizing dye(s) used to increase color
sensitivity is inside the emulsion itself and is relatively difficult to
remove. Most is removed in the developer also, but some remains throughout
the processes if a really though washing is not done. Retention of some
color is not really a problem unless you think it is.

Truly, dr bob.

Reply to this Message