This is topic Fading Solved? Or so it says ... in forum 8mm Forum at 8mm Forum.


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Posted by John Whittle (Member # 22) on May 08, 2008, 09:38 AM:
 
Some time back I mentioned a patent I had run across that was granted recently (2003) which claims a treatment for faded motion picture film. With a couple of simple devices and some chemistry which is fumed into a processed print, the inventor says that film colors are restored.

I haven't heard of anyone using this process or it's commercial availability, but present it here for all of you to consider and research.

The full patent can be seen here: Color Fading Patent

John
 
Posted by Osi Osgood (Member # 424) on May 08, 2008, 10:32 PM:
 
I'm going to take a look at that John, when I get the chance.

At the local High school, they have thier photography class, and if this is a concoction that can be mixed up at home, (snicker) or in thier lab, then I'd be happy to try it out on one of my beloved films!

Continuing on my post, I just looked at it, (as I'm sure that John Whittle has done ...

John ...

It appears that the film never actually comes into contact with the solution, and that the solution is warmed to the point of vapors, and these vapors permeate said film, and then the film is exposed to sunlight.

My questions are :

I don't see anywhere where it says how long the film is exposed to the vapors, if the film is sealed in with the vapors, (actually I assume the device has some form of ventilation)
Is this process done in a darkroom?
AND

How long afterwards the film is exposed to sunlight.

I'm not sure, but it appears that perhaps, while it cannot possibly restore the dye layer that has disappeared, (if it has disappeared) it gets rid of the overwhelming 1. dye level 2. browning or pinking.

Gee, I'm almost sounding like I'm actually understanding what is going on!
 
Posted by Kevin Faulkner (Member # 6) on May 09, 2008, 04:28 AM:
 
In colour film the colour Couplers which give you the final dye image are colourless until they enter the colour developer. The couplers crosslink with the developing agent formimg the final dye you see.
Cyan dyes were notorious for being unstable and I think what happens is that they don't actually fade away but turn back to their colourless state with age if that makes sense. In other words they are still there but clear.
I have always felt that if this is the case then there must be some process which would allow the dyes to be restored. Even though I did chemistry at school/College I don't fully understand this process.
If on the other hand the dyes of the other layers are being faded to match the now faded cyan then you are going to end up with a very washed out looking print.

As for Black and White film I can only think its sort of making the silver sensitive to light again so that when its exposed to light once more the density increases. Obviously it would increase in the area containing the most silver i.e. the shadows. This would then give the appearance of increased contrast. This would perhaps tie up with the comments that sepia prints can be restored to normal as it would be reconverting back to solid silver.
I see this patent was filed back in 2003 so if it does indeed work why has no one taken this up as a restoration service?

John, what do you think about this and any idea how its working. Does anyone know a scientist/chemist?

Kev.
 
Posted by Keith Ashfield (Member # 741) on May 09, 2008, 04:37 AM:
 
Kevin, I don't know of any scientists, but I can recommend Boots the Chemist. [Big Grin]
Back in the cell before Nurse Ratchett comes!! [Confused]
 
Posted by Osi Osgood (Member # 424) on May 09, 2008, 09:07 AM:
 
Are these chemical agents readily available, (without the FBI coming down on your butt?)?

Hey, I'd volunteer on e of my fading prints, just to find out if the process actually works.

If Kevin is right, (and he'd know better than I), if it would, lets say, do away with the cyan level which no longer exists, it seems like you would end up with what they had in the 1920's the two color technicolor process which, while it didn't do a bad job, lets face it, it taint Technicolor!
 
Posted by John Whittle (Member # 22) on May 09, 2008, 07:58 PM:
 
Kev

I agree with your theory. I think what's supposed to happen is to restore the cyan dye by re-activing the chemical reaction. Rather than treating it in solution it's treated with a vapor of the chemicals (which aren't exotic by the way). Just why treating the film with his light box "fixes" the transformation I don't really understand. Of course no where in the patent is the spectrum of the light specified and it could be anywhere from infrared to ultraviolet.

The chemcials are specified and in a rough approximation of the mixture. I would think that the treatment would have to be adapted for different stocks which used different dyes/couplers.

Osi,

Don't pull a whole print, for testing purposed you'd only need a short strip of film much like we'd run strips for process control. A faded 50 foot subject could provide 100 test strips (or 99 strips and a control or untreated piece).

The other unknown is how long the "fix" or "repair" would last. The process seems simple enough and in theory could work. I've just never heard of any commercial application and you'd think if it was working someone would be offering the service.

John

(PS I tried to post a drawing of the fuming chamber with the original post but the forum was rejecting my picture, it let me upload but not link--claimed it was from an outside server!).
 


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