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Aurum
06-17-2008, 07:04 PM
The firebrigade of Laxenburg / Austria investigating the possibilities to extinguish burning nitrofilm in 1965: http://video.google.de/videoplay?docid=7892683211336574432&q=feuerwehr&total=2803&start=0&num=20&so=1&type=search&plindex=1

If anyone has any waste Nitrate base left I could do with some next time I need to light the Barbeque!

The Water fairies hit it with everything they had and it still stuck up two fingers at them :o

Kino
06-17-2008, 08:09 PM
I actually have 100 feet of it in the freezer; unexposed Panchromatic Negative stock (Kodak motion picture -- forget type) from the 30's. Base plus fog is about .30!

Emulsion
06-18-2008, 03:26 AM
I am trying to think of a single type of film still available off the shelf that is acetate and cannot.

You can special order acetate from Kodak in motion picture emulsions, but you have to buy 100,000 feet minimum if there are no remaining stocks ...

I have used a bit of 35mm motion picture film. All of the film I have come across recently appears to be acetate. It is easily torn if required....essential in my experience loading a motion picture film magazine. My understanding is that acetate is also essential as it will tear not strip the $200K movie cameras gears.

Small quantities (100ft) of surplus 35mm film is available from many companies for minimal cost. These are re-cans or "short ends".
http://www.stockoptionscorp.com/
http://certifiedfilm.com/
http://www.releasing.net/rawstock/
And an article on same...not by me.
http://www.scottspears.net/shortendsarticle.htm

The Kodak motion picture products catalogue shows the films that are polyester or estar. Mostly print rather than neg film.
http://www.kodak.com/US/plugins/acrobat/en/motion/catalog/completeCatalog.pdf

Hope this helps somemone.

Emulsion

Simon R Galley
06-19-2008, 07:44 AM
Did not see the question for me : So sorry for the delay

We coat miniature and roll film on tri-acetate, sheet film on polyester :

We would never coat miniature or roll on polyester, due to the hightened
possibility of camera damage, polyester does not tear and therefore in our
opinion is not suitable for a camera film base, so we do not use it.

POLYESTER is OK for lots of other miniature applications such as aerial / surveillance
etc. etc. and its thinner so it has other advantages in certain applications

Regards Simon ILFORD Photo / HARMAN technology Limited :

Aurelien
06-19-2008, 07:51 AM
Dear Simon,

I agree with you concerning the 35mm format : if it can't tear, you can damage camera. But in 120, what is the problem?

Kino
06-19-2008, 07:58 AM
Well, what do you know? I stand corrected!

As to camera damage, never saw it in 13 years of about 1 million feet of polyester a year through precision Oxberry and Mitchell camera movements in our optical printers and film recorder.

Only damage I ever saw as a direct result of polyester was a bent film processing rack on our continuous processing machine.

But, it never hurts to be safe, I guess...

Photo Engineer
06-19-2008, 08:57 AM
I have seen camera damage as posted here and elsewhere.

Kodak follows the same guidelines as Ilford in film base use. The only place polyester is used is in space photography where weight and film length is of concern. Kodak coated on 2 mil (0.002") support or thinner to meet NASA specs.

PE

Steve Smith
06-19-2008, 09:06 AM
Kodak coated on 2 mil (0.002") support or thinner to meet NASA specs.

I bet that involved some challenges. Our printers complain if we quote a job on anything thinner than 0.004" polyester.


Steve.

Michel Hardy-Vallée
06-19-2008, 09:16 AM
I agree with you concerning the 35mm format : if it can't tear, you can damage camera. But in 120, what is the problem?

To avoid damage on motorized 120 backs?

David A. Goldfarb
06-19-2008, 09:32 AM
Not just motorized backs. Some cameras (Pentacon 6, Mamiya 6, Bronica S and S2) are known for having film advance issues or potential for stripped gears.

Photo Engineer
06-19-2008, 09:41 AM
I bet that involved some challenges. Our printers complain if we quote a job on anything thinner than 0.004" polyester.


Steve.

Steve;

Not really. The problem was adjusting the film backs to use the thin based film. It was supplied as motion picture and as 120 film both. One used in the capsule mo-pic cameras IIRC and on the ground, and the other was for the Hassie in orbit and on the moon. (oh, I forgot, the moon stuff was all faked. :D )

The ground motion picture was such high speed, they needed thin film to get more footage into a standard magazine. I've mentioned before that I saw it jam and spew the camera guts along with sprocket gears all over the test lab.

The high speed camera had a gear shift type of arrangement to get up to speed so as not to damage the equipment by a sudden jolt of full power. This is also true of high speed coating machines coating polyester. They ramp up to coating speed. This of course, wastes a lot of start up footage so you have to want to coat a lot of film to make a profit and overcome waste. Experiments are done at very low speed to eliminate this problem.

Also, you must remember that polyester cannot be coated on directly. It needs a corona discharge to pre-condition the film to accept the aqueous gelatin emulsion.

PE

Aurelien
06-20-2008, 06:26 AM
So, the same emulsion can be coated either on acetate or on PET, without any difference?

Photo Engineer
06-20-2008, 08:28 PM
Just about.

PE

kevs
03-17-2013, 01:42 AM
Hi all, I'm reviving this thread because it discusses vinegar syndrome, the subject of my post. The admins can move it if necessary to the appropriate place.

I'm currently scanning some colour negatives that my father exposed in the 1960s and 1970s for retouching and archiving. Some of these (too many!) are cut into individual negatives - as seemed to be the norm back then. On these individual negs, there's a distinct line of tobacco-brown 'stain' (in positive) along the edges of the image area adjacent to the cut edges. The film is 120 format, Kodacolor X and Kodacolor II, and the former appear more affected by this (because they're older, or different process?). These have been stored in mostly glassine neg bags inside paper envelopes in UK domestic conditions, not particularly humid.

I wonder whether this could be the starting point of vinegar syndrome deterioration, or is it something else - environmental contamination perhaps?

Here's an example; note the discolouration along the top edge: http://s20.postimage.org/4okhy9afh/abington4.jpg

Cheers,
kevs

Photo Engineer
03-17-2013, 10:07 AM
This is not, in any way, related to "vinegar smell" or "vinegar syndrome".

It may be fungus attack or it may just be that the stabilizer is running out of potency.

A dip in old style Formalin Stabilizer and then drying might halt the process. OTOH, it may just be heat induced dye fade.

BTW, the example is rather hard to see.

PE

Mustafa Umut Sarac
03-17-2013, 01:04 PM
oh, I forgot, the moon stuff was all faked.

I swear on Bible , I saw an palm tree at moon shots , all was taken in Hawaii not at moon !

kevs
03-17-2013, 07:17 PM
This is not, in any way, related to "vinegar smell" or "vinegar syndrome".

It may be fungus attack or it may just be that the stabilizer is running out of potency.

A dip in old style Formalin Stabilizer and then drying might halt the process. OTOH, it may just be heat induced dye fade.

BTW, the example is rather hard to see.

PE

Thanks P.E. It's good to know it's not vinegar syndrome anyway. I wondered whether the base was starting to deteriorate considering their age. I haven't noticed any vinegar smell around them. There's no sign of fungus and I don't think heat is very likely since they've been stored in a dry, dark and mostly cool bedroom drawer since about 1970. However I can't comment upon their early life since I wasn't around then, and it's likely they've been exposed to fumes from woodwork, clothing, toiletries and other things that have been stored alongside them.

Here's a larger example from a different neg, showing just the affected area and surround for context: http://s20.postimage.org/ue4bjl79n/abington3.jpg. This is the 56mm slice across the film's width, exposed in a 6cm x 4.5cm (16-on-120) camera.

Still, nothing lasts forever, and when I'm dead I doubt anyone will care about them anyway. :-D

Thanks for your time and effort here, it's most appreciated. :-)
Cheers,
kevs

lxdude
03-17-2013, 08:10 PM
I swear on Bible , I saw an palm tree at moon shots , all was taken in Hawaii not at moon !

You assume there are no palm trees on the moon. If we've never been there, how do we know?;):whistling:

Photo Engineer
03-17-2013, 09:07 PM
Kevs;

If on the positive, you see a reddish yellow image, this means that those dyes are becoming absent in the original. These are affected by heat and humidity and the magenta, in particular, is affected by the lack of stabilizer.

PE

kevs
03-18-2013, 03:49 PM
Kevs;

If on the positive, you see a reddish yellow image, this means that those dyes are becoming absent in the original. These are affected by heat and humidity and the magenta, in particular, is affected by the lack of stabilizer.

PE

Thank you for the info P.E., at least I know what's going on. I'll bear it in mind when deciding how to store the collection, though I'm not sure i want to start soaking 40 year old negatives in anything. :-)

Cheers,
kevs