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Artifact: What's the cause?

Worker 11811 said:
A 100ºF presoak? That sounds like you're just begging for reticulation to me! Really 100ºF?
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PE is referring to the C-41 processing for color print film.

Steve
 

If you are doing C41 or E6 this is reasonable. Also at that high temp, the drop in the first presoak is bad enough to need a second one. So, I use 2 30" presoaks at 100F and 1 presoak at 68F.

Reasonable?

PE
 

Air bubbles wouldn't sit in the place shown on your images. It looks like fixer or acid got "flicked" on the film right before developer.
 
One plus: you can say you have photographic proof that you were abducted by aliens and taken to another world which is an analog to this one, except that it has double black suns.
 
christom said:
Air bubbles wouldn't sit in the place shown on your images. It looks like fixer or acid got "flicked" on the film right before developer.
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Be sure to tell that to the folks at Ilford who determined that it was air bubbles.:rolleyes:
 
I haven't had a single roll of Pan F+ without this. Yes, they're air bubbles, no need for microscope. As a result, I dropped Pan F+ altogether, despite great tonality. Killed some of my best frames. I compliment Ilford for their great customer service, no irony here, but until they publish an unequivocal confirmation that they have fixed this "feature" of Pan F+ once and for all they're not getting this (lifelong, vocal) supporter back on the Pan.

Respectfully ripping open another brick of HP5+,

Vilk
 
I appreciate your view on this but I'm not ready to give up so quickly.

First, I have received specific advice via private e-mail about how to avoid this in the future. It's all common sense stuff but it basically means I have to redouble my efforts to make sure I agitate correctly and tap the tank enough to prevent the bubbles from sticking.

Second, I have received good advice from this forum, much along the same lines as the advice I received from Ilford, which will help me prevent the problem in the future.

Third, PhotoEngineer has given some good advice about prewetting film to help prevent air bubbles from sticking to the film.

Finally, I'm not a quitter. Unless and until this becomes an insurmountable problem I will keep using whatever film gives me the images I'm looking for. Up until this incident, I have NEVER had an air bubble ruin a photograph before and, given the advice I have received, I don't expect to have another one any time soon.

Vilk, I will take your advice at face value. For some reason, Pan F is prone to air bubbles sticking to the film. Now I know that. I'll watch out for it and I'll be careful about it.

If it does turn out to be a problem, I won't be able to say you didn't warn me. Right?
 
I wish I could say I coloured it up a bit.

Please post here when, after following all the good advice, you pull the tenth roll out of the tank and still find no bubbles. I'll go back to it in a blink. I cut my darkroom teeth on Ilford thirty years ago and I have never had a reason to look elsewhere--until this (it probably explains why it took me twenty rolls to give up and not one).

 

How do you expect a company to fix an issue that's down to your techniques rather than their product ?

There are ways to solve the problem but personally I don't think a pre-soak is a magic cure in many cases, I've found my way for the water here in Turkey, but there may be other ways for you.

Ian
 
Does nine count?

I developed nine rolls of Pan F+ before that happened. If I would have made one more, it would have been ten but I can not rule out the fact that I might have gotten just a little bit sloppy when I developed that last roll of Pan F.

I do not expect to see this problem again, to be honest.
Since January, I have developed almost 50 rolls of film. Not one has had any bubbles.
In my life, I have probably developed a couple-few hundred rolls of film. That doesn't make me an expert but it does mean that my batting average for this kind of problem is less than half of one percent. Pretty low.

Given the information I have learned from this forum, I'll be on my toes and watch out for the problem. Maybe you're right. I'll just have to double check and triple check my work. But, if what you say proves to be true, I won't say you didn't warn me.

I am just not the kind of person who gives up easily. I don't intend to give up on this, either.
 
Ian Grant said:
How do you expect a company to fix an issue that's down to your techniques rather than their product?
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Before I answer I must take exception to the premise--Pan F+ is the only out of many films I have processed over many years that exhibited this behaviour with terrifying regularity. I gave up when I realized I'm taking three or four shots of the same scene anticipating the bubbles, knowing they would be there. Around my darkroom I'm a reasonably well-behaved Vilk.

It's still a mass market product and it's been around for years. Likely, hundreds of thousands of people around the world souped a roll at least once. I don't think it's just Randy and Vilk scratching their heads. Ilford knows.

To answer your question--the scientific term is "fool-proofing". It works for other films, it can work for this one, too. I have confidence in Ilford.

Now, perhaps, we may have reached the limits of physics. Maybe you cannot make an emulsion with these characteristics without leaving it prone to trapping air bubbles at the surface. Engineering is nothing but trade-offs: is it better to have that perfect curve and lose Randy and Vilk, or should we rather make the curve a bit more mundane and keep these two donkeys in the stable?

Only the company accountant can answer that.
 
Why even think of blaming the product when it is a technique caused problem?
 
Worker 11811 said:
Does nine count?
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Well, once I spotted the first ones--like you did, against a bright, even sky--I knew what to look for. I went back and found many more, hidden in dense foliage, carpet patterns, stone textures...

I really wish it were nothing but my technique. Then I could use those few still left in my fridge.

See? I have a real incentive to find a Vilk-based solution!
 
richard ide said:
Why even think of blaming the product when it is a technique caused problem?
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Because the first twenty-nine "What did I do wrong?" bullet points checked negative?

I'm not "blaming" the product. I'm pointing out a way to make it better.
 
Well, when I learned how to develop film in tanks many years ago, I was taught to bang the tank against the palm of my hand to dislodge air bubbles. This works, but I still found that a prewet was nearly foolproof whereas banging helps to a certain extent depending on film. Now, I use a prewet and bang the tank during the prewet. (unless I am using the Jobo)

PE
 

An interesting possibility. I've seen these defects a number of tines with EFKE sheet film processed in a Yankee tank. I've always though they were processing problems, although they did not occur when I processed Ilford film in that tank. The Yankee tank requires you to agitate by violently shaking the tank from side to side (vertical motion and inversion are impossible due to construction). That can lead to some weird artifacts.
 
You can distinguish between a DEC and an air bubble by using a microscopic examination through the film or doing a cross section slice of the film and looking under a microscope. Either way, a DEC looks like a tiny crater with a trough running away at each side, while the air bubble looks like simply a lack of development surrounded sometimes by an edge of heavy or lighter silver depending on film.

The cross section is most definitive for a DEC as it is unequivocal. Sometimes, just looking down through the film at right angles to the support, you can be misled. In a cross section, a DEC resembles a mini volcano in the emulsion, with slight troughs off to each side.

PE
 
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