What has happened to my negatives?

Hexavalent · Feb 6, 2012

Removing entrained air:

Allow hot water to cool overnight in an unstoppered container, or a use vacuum pump. (or both)

I use both methods for carbon-transfer printing, which requires absolutely 'bubble-free' water.

Thomas Bertilsson · Feb 6, 2012

Brian C. Miller said:
What's the "best" way to remove them? Vacuum pump? For instance, I have a vacuum pump for sealing bags, and it has a jar attachment. I could fill a jar, and then apply a vacuum to it. (The Google search results are coming up with membrane devices, not solutions.)

I boil the water and let it cool.

removed account4 · Feb 6, 2012

Tronds said:
You can buy some books about developing and developers and start reading.
Besides that, introducing and keeping a possible source of problems, a step that isn't neccessary, when trying to solve a problem makes things much worse to solve. Eliminate all unneccessary routines and work from there. The problem may be complex. It can be a combination of pre-wetting and insufficient agitaiton. Eliminating the element that isn't neccessary costs nothing and even makes it less work. Why this is such a big problem for many in here is something I don't understand.
Attacking me and demanding a proof for problems caused by pre-wetting leads to nothing. I don't use pre-wetting, have never used it in the more than 30 years I have been developing my own films, both b&w and color. Because of that I can't have any images to present in that matter.
The only problems I hva had with uneven development is with a two-bath developer. Insufficient agitation of the second bath gave almost identical streaks and uneven development as the OP. Continous agitiation was required to get even development.
As this sceneario in a way resembles a pre-wetted film I suppose this film-developer combo requires more agitiation than what is used and recommended without pre-wetting. It is quite simple to check if this is the problem. Just drop the pre-wetting.
Ok I am swearing in the church again, but I don't care.
What website you find thrustworthy or not is your problem, not mine. There are several reports on several places on the web that pre-wetting MAY cause problems with uneven development and streaks. That is more than enough for me to just avoid this extra and unneccessary step.

hi tronds

i think the problem is that people generally don't like change from their normal routine.
they are used to what they do, and how they do it, and see no need to stray from their path ..
but like you, i don't see what the problem is if someone has trouble processing film,
and they are troubleshooting .. they should have an open mind and take everything into consideration.

i guess the pre-wet streaking you are talking about look pretty much the same as the negatives posted in the opening of this thread
( which also look like bromide drag and other things )?
i was under the impression that the streaking you mentioned was from your 2 bath developer, and since you don't use a water bath
it wasn't from a pre-wet, that is why i asked what pre-wet streaking &c looked like .

luckily i haven't had that sort of trouble ( knock on wood ) ...

swear in church all you want, morten used to swear in the church of rodinal all the time ..

john

pbromaghin · Feb 6, 2012

Tronds said:
You can buy some books about developing and developers and start reading.

I have books and have been doing a lot of reading. You know more than I do and I was hoping to add your source to my reading list.

Tronds said:
Besides that, introducing and keeping a possible source of problems, a step that isn't neccessary, when trying to solve a problem makes things much worse to solve. Eliminate all unneccessary routines and work from there. The problem may be complex. It can be a combination of pre-wetting and insufficient agitaiton. Eliminating the element that isn't neccessary costs nothing and even makes it less work.

A very sensible approach. I don't use pre-wet. I am ignorant on the issue. However, that it introduces problems is at this point just an unsupported assertion and simply repeating it ad nauseum does not support it. PE, on the other hand, described in detail an experiment explaining at the microscopic level just how it can be a benefit.

Tronds said:
Why this is such a big problem for many in here is something I don't understand.

This is not the problem that people are having. The problem is that you are making an unsupported assertion in an argument against a proven credible source. Oh, and calling someone a shithead and then complaining about incivility does not exactly enhance ones credibility.

Tronds said:
Attacking me and demanding a proof for problems caused by pre-wetting leads to nothing. I don't use pre-wetting, have never used it in the more than 30 years I have been developing my own films, both b&w and color. Because of that I can't have any images to present in that matter.

Just where did I attack you? I asked you to point me to where I could read something that supports your claim. Well, I suppose somebody who can find offense in anything Tom Bertilsson writes can call anything an attack.

Tronds said:
The only problems I hva had with uneven development is with a two-bath developer. Insufficient agitation of the second bath gave almost identical streaks and uneven development as the OP. Continous agitiation was required to get even development.
As this sceneario in a way resembles a pre-wetted film I suppose this film-developer combo requires more agitiation than what is used and recommended without pre-wetting. It is quite simple to check if this is the problem. Just drop the pre-wetting.

Again, a very sensible approach. I have often wondered if two-bath developer would be worth the extra trouble. This gives me another reason not to try it.

Photo Engineer · Feb 6, 2012

All of the methods of removing entrained air are valid. We had a device on the tap that made the bubbles coalesce and form huge bubbles. I believe it was called a vacuum breaker. The Jobo washer has one of these devices on the hose at the end and it does a remarkable job washing. You see, the bubbles can also form during washing and create spots of unwashed film or paper which then brown up later. So a bubble remover is used for wash as well.

I think that distilled water would be rather free of this problem.

Anyhow, I throw it out there on the table. You see, I am not one to say this or that is right, I merely suggest the prewet to anyone with development problems as it has, in my experience, aided uniformity, reduced air bells and given better temperature uniformity from process to process. It brings my equipment up to the proper temperature. OTOH, I also say "use what works".

And remember that in my nearly 60 years of experience, I was often processing 100 rolls of film or several hundred prints each day and sometimes using 3 or more processing methods (machine, hand tank, dip and dunk, tray and etc.. Some had prewet and some did not. In general, when we had a problem and there was no prewet, we added one. It almost always worked unless there was another problem in addition.

PE

removed account4 · Feb 6, 2012

SNIP

pbromaghin said:
I have often wondered if two-bath developer would be worth the extra trouble. This gives me another reason not to try it.

2 bath developers are very worthwhile, depending on what you are trying to do.
divided d 23 has been around for along time and is a standby .. people swear by it.
i sometimes use a hard working and slow working developer together, one develops the contrasts
and hard bits, the other the highlights and soft bits ... it takes a little goofing around but it is well worth
the risk of screwing things up ...

like with everything in photography, YMMV
and what works for one person, might not work for another ...

john

Thomas Bertilsson · Feb 6, 2012

Yet another way to eliminate air bubbles from processing water is to use a replenished developer. It rests enough between processing cycles that air is virtually eliminated.

Photo Engineer · Feb 6, 2012

Thomas;

This is exactly in line with what I have learned while working on a photofinishing lab.

And, NEVER use a prewet with a divided developer. I have said that many times in many places.

PE

pbromaghin · Feb 7, 2012

jnanian said:
like with everything in photography, YMMV
and what works for one person, might not work for another ...
john

At my stage of photography, the simpler the better. I am so ignorant, I don't need anything complicating things any more than they already are. Maybe in a couple of years. Not now.

John, I really appreciate your trying to help, though. You are an absolute star.

I don't like the digital/analog divide. I prefer to think electronic/chemical.

When I get around people who know chemical photography, it's really intimidating. They know so much more than I and seem to take it all for granted that I should know all this stuff that I don't. They're worse than motorheads. You and PE aren't like that. That is really special. Thank you both.

removed account4 · Feb 7, 2012

your're nice pbromaghin ..
apug has given me lots of things since i signed on
and i enjoy giving back when i can ..

regarding the chemistry ...
to be honest, i have no clue, i don't know the science behind any thing
the additives, chelates, yadda yadda yadda, its all greek to me !

its all about having fun, and when it stops being fun --

john

Photo Engineer · Feb 7, 2012

Yeah, thanks. I think sometimes that I get too technical though.

PE

Neanderman · Feb 8, 2012

PE, for me, you can never get "too technical." It just pushes me to understand it.

Keep on keepin' on.

Ed

What has happened to my negatives?

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