Polypan F issues

AgX · Jan 15, 2014

q_x said:
Light is always leaking into all the canisters, so I'm keeping it all in a black bag after cutting it and rolling it into canisters. First three frames are usually a waste. The only exception (less light leaking in) was with a reusable spool with tight, wide padding of black Velvet.

So, the stronger stronger light-piping effect you observed was with single-use cassettes?

That is strange as the light piping effect should be independend of the kind of seal.

q_x · Jan 15, 2014

I believe so, AgX. Though it may be an issue of loading/unloading particular casettes in bright or not so bright conditions. Piping may spoil up to 4 frames with single-use casettes, and with the reloadable casette I have it was more like 1-2 frames. I have to agree, it's not quite rational.

David Lyga · Jan 15, 2014

Gerald C Koch said:
As such it does not have to meet the same rigorous quality control standards as regular film. Caveat emptor!

Gerald (or anyone) can we all safely conclude that movie film (possibly because of persistence of vision not mandating this) does not have the same rigorous QC standards afforded to 'still' film? It would be interesting to get a definitive answer to this question. - David Lyga

Xmas · Jan 15, 2014

David Lyga said:
Gerald (or anyone) can we all safely conclude that movie film (possibly because of persistence of vision not mandating this) does not have the same rigorous QC standards afforded to 'still' film? It would be interesting to get a definitive answer to this question. - David Lyga

The answer to your question is 'need to ask supplier', of each film, but there are two types of cine film

camera film
projection film

The camera film is normally low contrast, high speed for its grain, sprocket holes for (half frame) registration frame to frame, anti halation layers, anti static, etc.,...
The print film is used like silver bromide contact paper i.e. projection, fine grain, slow, with base and sprocket holes for wear and tear resistance.

Polypan is probably he latter, but the OPs problems are not necessarily quality assurance related, the unhardened film on PET base is really difficult to process successfully.

The light piping is normal with PET even with anti halation dye, Kodak suggesting loading cassette in dark room, in past. It light pipes even with IXMOOs.

AgX · Jan 15, 2014

David Lyga said:
Gerald (or anyone) can we all safely conclude that movie film (possibly because of persistence of vision not mandating this) does not have the same rigorous QC standards afforded to 'still' film? It would be interesting to get a definitive answer to this question. - David Lyga

No one cannot safely conclude that.

AgX · Jan 15, 2014

Xmas said:
The light piping is normal with PET even with anti halation dye, Kodak suggesting loading cassette in dark room, in past. It light pipes even with IXMOOs.

Light piping is normal with PET-films, as long as they are undyed.

q_x · Jan 15, 2014

Yups, it's undyed, completely clear, and I think it's projection film indeed, I've read somewhere about it.

Xmas · Jan 15, 2014

AgX said:
Light piping is normal with PET-films, as long as they are undyed.

The four PET films (none polypan) I have used all have had antihalation dye but still light pipe in factory velvet cassettes and IXMOO (Leitz concentric) I always load in e.g. shop doorway out of sun, and shoot blanks for frame 1 and 2, to avoid loss of frames... I store ready to use cassettes in opaque plastic tubs.

I'm real careful with the unhardened film as well.

pgomena · Jan 15, 2014

The problems in the first picture appear to be air bubbles on the film during development. You state that you rotate film in processing and do not "shake" or invert the container. Try a couple of sharp raps of the container against the side of the sink after you fill the container with developer to release the air bubbles.

q_x · Jan 15, 2014

It's the exact opposite, pgomena. Samples are positive, spots on the negative are black. Air bubbles would appear transparent on the negative and black on positive, I think.

Second film processed in constant temperature showed no spots

georgegrosu · Jan 15, 2014

q_x

Surface from emulsion side looks normal: semi-gloss, even, the spots look like silver, just really black from this side.
Base side has obviously no change, being glossy, but the spots look opaue-gray, brighter, than the silver. From what I can tell by just looking, it may be either a huge deposit of silver (like when seriously overexposing and overdeveloping) or an unfixed but properly developed emulsion. Darkening can happen naturally, but I doubt if exposing any emulsion to light would darken it that much. There's no visible relief, no change in surface appearance. I've tried scratching it, there's no chance it's a flake or dust stuck to the film, or any other foreign matter. Whatever it is, it sits within the emulsion itself.

"Made in EC", it says. "POLYSTAR".

I have encountered this type of failure on color negative film.
This material use for mechanical control of machine of processing.
It was an old color negative, after development this here and there glowing grains within the emulsion.
Color film is unexposed and use it to control machine of developed for scratch, zonaje.
When I use a piece of fresh film,disappeared those failures.
Take a piece of film about 3 m and examine it to light.
You'll see those bright grains on undeveloped film.
If this film filmy is developed the grains will have an light color than black film.
A fresh film ...

George

q_x · Jan 15, 2014

georgegrosu, I have only five or so films unexposed, taking out even one is a loss, cause it's really hard to get any material without AH layer here on local market, and it's hard to get the same effect otherwise (only using blue filter comes to my mind). However, I think what I can do in the future is to cut a 5 to 10cm piece out of every roll for examination while putting the film into canisters or just before development.

Thanks again to all of you!

AgX · Jan 15, 2014

Xmas said:
The four PET films (none polypan) I have used all have had antihalation dye but still light pipe ...

It depends on the location of the antihalation layer whether to hamper light-piping or not.

AgX · Jan 15, 2014

Xmas said:
The answer to your question is 'need to ask supplier', of each film, but there are two types of cine film

camera film
projection film

There are much more cine films.

StoneNYC · Jan 15, 2014

After reading all of this I have only two comments.

One, this "no-pre-soak" is nonsense, always pre-soak your film if you want consistent results.

Two, these are air bubbles, tap your film canister after every inversion/rotation, loud enough to annoy the person in the next room. One two for every roll of film in the canister +1 souf you have only one roll, 2 taps, if you have 2 rolls, 3 taps. Etc.

Your air bubbles were so big, it trapped developer INSIDE the air bubble, hence the rings.

Done

AgX · Jan 15, 2014

Those artefacts are no air bubbles.

miha · Jan 15, 2014

I heve read probably two dozens of book devoting to darkroom techniques, mostly in in my teen years. Most of the books were European, some American. There was not a single book I read promoting pre-soak, including The Morgan&Morgan Darkroom Book where one of the co-authors was Grant Haist. The only exception was The Negative by Ansel Adams. That said, I have been developing film consistently for the last 20 years with consistent results and no pre-soak, not even once. In fact I first heard about the need of presoking from photo forums, promoted mostly by LF photographers.

Xmas · Jan 15, 2014

AgX said:
It depends on the location of the antihalation layer whether to hamper light-piping or not.

The Adox cts100 has it front & back. Is it possible to embedd dye in the PET?

donkee · Jan 15, 2014

I have shot probably 20 rolls so far. I actually like the stuff, I am not right though.

I do no presoak but to bang the tank for air bubbles.
D-76
Stop - Straight water for a 1 minute, constant agitation
Fix
quick rinse
HCA
rinse
wetting agent
Hang to dry

I haven't seen anything like this so far. I have heard of issues with an acid stop bath. I might try it on my next couple rolls to see if anything happens.

That is all I got.

Xmas · Jan 15, 2014

StoneNYC said:
After reading all of this I have only two comments.

One, this "no-pre-soak" is nonsense, always pre-soak your film if you want consistent results.

Two, these are air bubbles, tap your film canister after every inversion/rotation, loud enough to annoy the person in the next room. One two for every roll of film in the canister +1 souf you have only one roll, 2 taps, if you have 2 rolls, 3 taps. Etc.

Your air bubbles were so big, it trapped developer INSIDE the air bubble, hence the rings.

Done

How many tanks have you damaged?
http://www.badassoftheweek.com/wittman.html

David Lyga · Jan 15, 2014

Hopefully, AgX, that is true about not being able to come to definitive conclusions about better quality control on non-cine films. - David Lyga

AgX · Jan 15, 2014

Basically it is the client who decides what quality he accepts. And a artefact spoiling a still-photo may be hardly visible on a single frame in cine projection.

But a film manufacturer who did so many efforts in excluding artefacts by fine tuning his production system will likely be doing counterproductive work if he tries to allow artefacts again for a certain production.

AgX · Jan 15, 2014

Xmas said:
The Adox cts100 has it front & back. Is it possible to embedd dye in the PET?

There is no film with two AH-layers.

With Adox CTS 100 Adox improvised a solution against a lightpiping by giving the film a light protective back-coating.
(One could see this improvisation also as new approach in film-design. It depends on perspective...)

Of course PET can be dyed. Think only of clothing and bottles.

Xmas · Jan 15, 2014

AgX said:
There is no film with two AH-layers.

With Adox CTS 100 Adox improvised a solution against a lightpiping by giving the film a light protective back-coating.
(One could see this improvisation also as new approach in film-design. It depends on perspective...)

Of course PET can be dyed. Think only of clothing and bottles.

http://www.adox.de/english/ADOX Films/CHS100_II/index.html

front and back= 2?
the dye needs to wash out? or enlarging might be difficult?

AgX · Jan 15, 2014

You mix up three different dyes: the AH-dye, the light-protecting dye and the light-transmission reducing dye.
All at different locations, in different concentrations, with different working modus, lasting and non-lasting.

Polypan F issues

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