The pretty close to definitive guide to how you screwed up

[lamerko]

Yeah, I'm not going to shoot anything important...

 

[Donald Qualls]

The backing paper isn't designed to be completely light tight with just a single layer.

And yet I've used 120/620 film in a red-window camera with the red filter gone and only a couple frames that sat for a long time with direct sun on the window had visible fogging in the images. It might be different if you develop unexposed film after such abuse, but I certainly wouldn't expect to see visible doubling or print-through after a box speed exposure through the backing paper.

Even the antihalation layer in many 35 mm and sheet films is good for five stops of attenuation if the film is loaded back side forward; backing paper ought to be more opaque than that.

 

[MattKing]

I'd be more concerned with how effective the backing paper was when I opened the camera and discovered that the film was backwards on the takeup spool.

 

[Donald Qualls]

I'd be more concerned with how effective the backing paper was when I opened the camera and discovered that the film was backwards on the takeup spool.

By that time, the tail should be wrapped up over the film just as it would be normally -- only black side out. Stick a rubber band on it, drop it into a 120 film can, and rewind it to an empty spool in a dark bag or darkroom and it ought to be fine.

 

[MattKing]

By that time, the tail should be wrapped up over the film just as it would be normally -- only black side out. Stick a rubber band on it, drop it into a 120 film can, and rewind it to an empty spool in a dark bag or darkroom and it ought to be fine.

Yep - "should be".
My wife comes from a counselling background. She tells me that "should" is a "cognitive distortion" .
Sometimes the backwards wound film is sitting very well behaved on that take-up spool.
And sometimes not so much!

 

[snusmumriken]

My wife comes from a counselling background. She tells me that "should" is a "cognitive distortion"

What does she say about “ought”?

 

[MattKing]

What does she say about “ought”?

I'll have to ask her .
EDIT: she laughed!

 

[snusmumriken]

I'll have to ask her .
EDIT: she laughed!

 

[malias]

Thanks !