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Author Topic: Film Scratches
Paul Adsett
Film God

Posts: 5003
From: USA
Registered: Jun 2003

- posted February 25, 2005 08:08 AM      Profile for Paul Adsett     Send New Private Message       Edit/Delete Post 
Some questions on the causes of film scratches.
How can you tell if a film scratch originates from the negative of the print ,or from the projector? Is it true that a projector related scratch will always be visible as a black line, whereas a negative scratch will always be a yellow or green line? What is the difference (on the screen) between an emulsion side scratch vs a base side scratch? And is the emulsion side of the film towards or away from the projection lens?

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003

- posted February 25, 2005 10:58 AM      Profile for Kevin Faulkner         Edit/Delete Post 
Emulsion side of the film is normally towards the lens i.e. facing out from the spool. Some contact prints are the other way about but this is seldom used for small format printing. Most are optical prints.
Emulsion scratches will normally show up as green/yellow lines but this depends on how deep the scratch is.
Base scratches will show up as black. This is because the light is scattered within the scratch instead of going straight through.
The same applies when the prints are made. As light is scattered within the scratch on the negative, less light will be transmitted onto the print film with the result being that the scratch will be printed as a white line.
Hope that explains that ok? Kev [Smile]

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GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Brian Hendel
Jedi Master Film Handler

Posts: 902
From: New York, New York
Registered: Jun 2003

- posted February 25, 2005 11:12 PM      Profile for Brian Hendel     Send New Private Message       Edit/Delete Post 
I have noticed something else with scratches that mystifies me. When I use a film cleaner the lighter black lines disappear but only temporarily. When the film dries and I watch it days later the black lines are back! How can a cleaner remove the lines just briefly. It makes no sense to me. Can anyone explain? [Confused]

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Jan Bister
Darth 8mm

Posts: 2629
From: Ohio, USA
Registered: Jan 2005

- posted February 26, 2005 01:04 AM      Profile for Jan Bister   Email Jan Bister   Send New Private Message       Edit/Delete Post 
Simple... the cleaner fluid fills in the scratches and smoothes them out - and having roughly the same optical properties as the film itself, light is no longer fractured and the scratches appear to vanish. They're actually still there, just hidden until the fluid evaporates (the film dries).
Just like if you were to fill the entire Grand Canyon with water. Sure, you'll get a smooth surface, but once the water drains, the canyon's back as it was before [Big Grin]

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Call me Phoenix. *dusts off the ashes*

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003

- posted February 26, 2005 12:28 PM      Profile for Kevin Faulkner         Edit/Delete Post 
Jan, that was a brilliant explanation. I like the Grand Canyon bit [Big Grin]
A good film cleaner with a lubricant is what as needed. The cleaner helps to get rid of the muck and then the lubricant hopefully stays in the scratch long term to make the scratches less obvious.
Some film cleaners dont have any lubricant and others have loads so its a matter of experimenting with different brands.

Kev.

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GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Dan Lail
Film God

Posts: 2110
From: Loganville, Georgia, USA
Registered: Jun 2003

- posted February 26, 2005 02:35 PM      Profile for Dan Lail   Author's Homepage     Send New Private Message       Edit/Delete Post 
Kev, any suggestions as which cleaner/lubricants to use?

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Mike Peckham
Phenomenal Film Handler

Posts: 1461
From: West Sussex, UK.
Registered: Jun 2003

- posted February 26, 2005 05:41 PM      Profile for Mike Peckham   Email Mike Peckham   Send New Private Message       Edit/Delete Post 
quote:
Kev, any suggestions as which cleaner/lubricants to use?
Oh no, here we go again, this could run on for pages [Frown] .

Mike [Wink]

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Auntie Em must have stopped wondering where I am by now...

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Jan Bister
Darth 8mm

Posts: 2629
From: Ohio, USA
Registered: Jan 2005

- posted February 26, 2005 08:57 PM      Profile for Jan Bister   Email Jan Bister   Send New Private Message       Edit/Delete Post 
Kevin: thanks [Big Grin] btw, might be time to lock this thread and link to that other one where all the film cleaner talk took place before [Smile]

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Call me Phoenix. *dusts off the ashes*

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Mark Norton
Master Film Handler

Posts: 330
From: Hampton Hill, Middlesex, U.K.
Registered: Feb 2004

- posted February 27, 2005 05:39 AM      Profile for Mark Norton   Author's Homepage     Send New Private Message       Edit/Delete Post 
I,ve been using classic home cinemas film cleaner Crestaclean in my spondon film cleaning machine and it's very good, does not evaporate very quickly and leaves a good deposit over the film which hides those 'black type' of scratches. However it has a very stong smell which lingers around for hours after using it.

If I suspect any of my projectors of scratching film I allways run a loop test, removing parts untill the problem is identified. I believe you need to be 110% sure of your machine before you lace up that £300+ feature.

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003

- posted February 27, 2005 06:31 AM      Profile for Kevin Faulkner         Edit/Delete Post 
There are many good lubricants about. Cresclean as mentioned by Mark is excellent as is FimRenew and FilmGuard to name a few.
What you need is a cleaner where the solvent evapourates fairly rapidly and leaves a good coating of lubricant behind. Those mentioned earlier do just that.

Kev.

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GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Adrian Winchester
Film God

Posts: 2941
From: Croydon, London, UK
Registered: Aug 2004

- posted February 27, 2005 10:28 AM      Profile for Adrian Winchester     Send New Private Message       Edit/Delete Post 
If anyone is keen to remove/reduce scratches permanently, and is willing to spend some time doing so, the 'water treatment' is the way to do it. Note, however, that this only works on scratches on the emulsion side - it has no effect on base scratches. I've treated quite a bit of S8 but I used it on a few 16mm shorts recently and I was surprised how effective it was. I don't have the time to give full recommendations on how to approach it now - and there are certain problems that you need to take care to avoid - but if anyone wants to try it, say so here, and I'll provide full details in a few days time.

Adrian

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Adrian Winchester

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Jan Bister
Darth 8mm

Posts: 2629
From: Ohio, USA
Registered: Jan 2005

- posted February 27, 2005 11:18 AM      Profile for Jan Bister   Email Jan Bister   Send New Private Message       Edit/Delete Post 
That reminds me of something... I made a near-fatal mistake just the other day in that I used rubbing alcohol to clean the film path in my Elmo projector. Now we're talking here about the stuff you get at the pharmacy which has 70% alcohol and 30% water in it. Let's just say I forgot about the composition of it [Embarrassed] so when I ran a film through the unit after cleaning, everything seemed fine, great picture, until I stopped the film and ran it in reverse just to test that function. All of a sudden: black splotches all over the screen! Same thing when I ran it in forward again - right up to the point at which I had gone to reverse, then the image cleared right up again! So I stopped the projector and opened the cover, and lo and behold the magnetic soundtrack was practically spewing oxide dust all over the insides. It was then that I realized the water portion of the rubbing alcohol was attacking the film and causing the magnetic particles to come off. AUGHH [Eek!]
Fortunately, a quick treatment with a cloth soaked in FilmRenew, and a complete re-cleaning of the film path (this time with Goo-Gone) averted permanent damage to my film - the splotches are gone altogether and no harm is done. WHEW. [Smile]

My point? Just wanted to warn you folks: rubbing alcohol is good stuff to clean sound heads, (if you wipe them dry afterward), but don't use it on the rest of your projector [Roll Eyes]

EDIT

Hmm, as I'm thinking about what I just wrote, I'm beginning to wonder whether this would work: wind your film to be treated onto a metal reel... soak the entire reel in WATER... after one minute or so, take it out and immediately soak it in FILMRENEW... Nahhh, forget it. I don't want anyone ruining their films because of a silly idea going through my head. [Cool]

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Call me Phoenix. *dusts off the ashes*

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Mark Norton
Master Film Handler

Posts: 330
From: Hampton Hill, Middlesex, U.K.
Registered: Feb 2004

- posted February 28, 2005 01:41 PM      Profile for Mark Norton   Author's Homepage     Send New Private Message       Edit/Delete Post 
Water treatment? [Eek!]

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Dan Lail
Film God

Posts: 2110
From: Loganville, Georgia, USA
Registered: Jun 2003

- posted February 28, 2005 01:58 PM      Profile for Dan Lail   Author's Homepage     Send New Private Message       Edit/Delete Post 
Thanks, Mark, I'm soaking all my prints in water as we speak. [Big Grin] Mike, I didn't realize bringing up the clean/lube thing would set off a chain reaction. [Wink] I guess I should have done a post search.

P.S. Just kidding about the water soak. Please, do not soak your prints in water, except maybe "The Rose". I think it's probably waterproof(a real tear jerker)! [Razz]

[ February 28, 2005, 10:03 PM: Message edited by: Dan Lail ]

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Michael De Angelis
Phenomenal Film Handler

Posts: 1261
From: USA
Registered: Jul 2003

- posted February 28, 2005 09:42 PM      Profile for Michael De Angelis   Email Michael De Angelis   Send New Private Message       Edit/Delete Post 
As I had learned and mentioned in an earlier thread, I had aired out a film that had a terrific smell of mildew. After several repeated days of airing out on the back screened porch, I had forgotten the reel of film outdoors when it began to storm one evening.
Before my head hit the pillow I remembered, and ran out to retrieve the film.
Upon close inspection the spray from the rain began to weld the layers of film together.
Slowly I began to separate the film, inspecting it and allowing it to dry before winding it slowly back onto a take-up reel.

Evidently, many blemishes disapeared, but I could have lost the entire film.

Michael

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Jan Bister
Darth 8mm

Posts: 2629
From: Ohio, USA
Registered: Jan 2005

- posted February 28, 2005 10:00 PM      Profile for Jan Bister   Email Jan Bister   Send New Private Message       Edit/Delete Post 
I remember that story. Which film was it, anyway? *curious*

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Call me Phoenix. *dusts off the ashes*

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Dan Lail
Film God

Posts: 2110
From: Loganville, Georgia, USA
Registered: Jun 2003

- posted February 28, 2005 10:07 PM      Profile for Dan Lail   Author's Homepage     Send New Private Message       Edit/Delete Post 
Definately do use alcohol on rubber parts(pinch rollers). It will make them swell up. Instead, use rubber cleaner. [Smile]

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Michael De Angelis
Phenomenal Film Handler

Posts: 1261
From: USA
Registered: Jul 2003

- posted March 01, 2005 10:59 PM      Profile for Michael De Angelis   Email Michael De Angelis   Send New Private Message       Edit/Delete Post 
Hi Jan,

It was a 16mm two reel short, from the Hal Roach Taxi Boys series with Billy Gilbert and Ben Blue titled: Taxi For Two. [Smile]

Michael

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Isn't it great that we can all communicate about this great
hobby that we love!

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Tony Milman
Phenomenal Film Handler

Posts: 1336
From: United Kingdom
Registered: Jun 2003

- posted March 02, 2005 03:15 PM      Profile for Tony Milman   Author's Homepage   Email Tony Milman   Send New Private Message       Edit/Delete Post 
I still find the top basket of my Bosch Dishwasher gives great results. [Wink]

Dan. My wife expressed interest in your recommended cleaner [Big Grin]

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Tony

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Adrian Winchester
Film God

Posts: 2941
From: Croydon, London, UK
Registered: Aug 2004

- posted March 06, 2005 01:48 PM      Profile for Adrian Winchester     Send New Private Message       Edit/Delete Post 
Do you guys really believe the water treatment is a joke!? If so, you are welcome to come round to my home (south London) and I'll demonstrate it being done! And bring a scratched film with you if you wish.

And if you still think I'm making this up, I might be able to find the 1980s issue of 'Movie Maker' magazine, where respected writer Ivan Watson mentioned it in an article which first brought it to my attention.

Adrian

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Adrian Winchester

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Mike Peckham
Phenomenal Film Handler

Posts: 1461
From: West Sussex, UK.
Registered: Jun 2003

- posted March 06, 2005 04:05 PM      Profile for Mike Peckham   Email Mike Peckham   Send New Private Message       Edit/Delete Post 
Adrian, I remember that article. I'll see if I can find it, Ivan Watson was a great advocate of water treatment for hiding emulsion scratches.

Mike

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Auntie Em must have stopped wondering where I am by now...

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Kevin Faulkner
Film God

Posts: 4071
From: Essex UK
Registered: Jun 2003

- posted March 06, 2005 05:14 PM      Profile for Kevin Faulkner         Edit/Delete Post 
Well it seems we are going down the same ropute as a previous thread. See "Film Renew" in the 8mm Forum and the topic or wetting film and what was said about it is there for all to read.

Kev.

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GS1200 Xenon with Elmo 1.0...great combo along with a 16-CL Xenon for that super bright white light.

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Adrian Winchester
Film God

Posts: 2941
From: Croydon, London, UK
Registered: Aug 2004

- posted March 07, 2005 06:49 AM      Profile for Adrian Winchester     Send New Private Message       Edit/Delete Post 
Kevin,
I missed your post on that one but I've just looked it up. I use a slightly different approach which I certainly would not claim is better but seems to work for me. I fill a bath with 3-4 inches of warm water, adding (as you do) a water softener like washing up liquid. (Incidentally, I once treated a 50ft short in the sink of my hotel when in Blackpool for the convention, and as the water is soft there, it was no problem to use it without adding anything!) I take care to 'wind it out' in a way that reduces the risk of it getting tangled when I remove it. After about 15 mins I take one end and pull it through part of a folded towel, to remove excess water. I then it spread out on a non-fluffy cloth to dry in a warm room. The danger at this stage is that some film stocks stick together if emulsion makes contact with emulsion, so I move the film 2 or 3 times while it's drying, trying to ensure that this does not happen. After about an hour, it can be rewound, and I also apply thermofilm to clean off any dust and to improve any scratches that have not been eliminated.
Adrian

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Adrian Winchester

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