The "Rail Effect" of mag-striped Film. Reality or Myth?

[Todd Kitchen]

Lenny Lipton mentioned the "rail effect" in one of his books.

Kodak claimed the rail effect was protective for sound cart film as well as post-striped film. The idea is that mag striped film is less likely to get scratched than silent. The stripes hold the film away from the other film layers on the spool and protect the emulsion. Especially useful if the film is cinched tightly on the reel due to user error or equipment malfunction.

I remember Lipton was a bit skeptical--what does the forum think?

[Joseph Banfield]

Interesting and it does make some sense as protection. I know that the balance stripe was added to eliminate winding problems and to make both edges equal to also avoid potential focusing problems, although there are many package films with only a main stripe and no balance stripe at all and I don't see focusing issues or problems of the film not winding flatly onto the reels. Perhaps it does help to some degree but I also have sound films that were bought used that have both emulsion and base scratches just like silent ones with no sound stripes at all. It must offer in practice very little protection but it does sound like great marketing from Kodak in my opinion.

[Osi Osgood]

In theory, it would be true, but the difference would be so marginal that, if you have a projector that is hell bent to scratch your film, it will get it's way!

[Todd Kitchen]

None of the footage I shot in the 90s/00s (mostly Kodachrome) has anything other than light base scratches, and I projected a lot of that footage thru some really questionable projectors. The very small amount of sound footage I took looks no better or worse than the silent, so maybe the rail effect was simply Kodak marketing.

[Brian Fretwell]

The "Rail effect" may have some advantage of dust not being able to get between the coils of film badly stored from the perforation side. No balance stripe could leave room for it to enter.