Can light from a watch ruin film development?

ornate_wrasse

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I was loading a roll of Tri-X in the dark onto the reel and realized that my watch was providing enough illumination to see things in the changing room at my local community college's darkroom. When I raised this issue a couple of weeks ago, my instructor said not to worry about it. So far, there doesn't seem to have been any effect on the film I've developed.

But I wonder whether this could be a problem in the future.

Has anyone experienced any problems developing film as a result of the light from their watch?

Thanks for your input. I am just starting to develop my own film and don't have enough experience at this point to know all the answers. :D

Ellen
 
I'm not sure what the 'real' answer is but I take my watch off when I'm loading film - just in case. I'm not so fussy when using paper.
 
I too remove my watch and place it face down on the counter before loading any film onto a reel. I've not had any bad experiences, but why look for trouble.
 
Watch out for watches with Tritium tubes in them (or if its really old, radium)... put some nice little marks on some 4x5 film by setting a Ball standard watch with luminescent tritium markers on the storage box for a few weeks. Extremely low radiation, but enough if you're a dummy like me and let the thing set there forever.

-roc

PS: tritium watches usually say "T SWISS MADE T" instead of just "SWISS MADE"... dunno what it says if your watch is made in Moldavia
 
Rule of thumb: When you can see things in the darkroom, it is not film safe - it may still be paper safe, but YMMV.

There are not that many watches so bright that they illuminate anything beyond themselves - phosphorescent dots are not bright enough, but backlit and LED watches may be. If you have a watch with torch-like backlight, you'd better leave it outside the darkroom. Mobiles are even worse, by the way, as they tend to burst into full illumination mode whenever somebody calls you.
 
I wear a Timex watch with the Indiglo light, although it won't light up on it's own you must push in a button, I do take it off before loading film in a changing bag...As stated above film needs Total Darkness...I'm not taking any chances...
 
Watch out for watches with Tritium tubes in them (or if its really old, radium).

The more so as that was a common illumination on old darkroom equipment. Mind, safe distances are about 10cm, so you are safe if you just don't use the old "permanently self-illuminated" lab timer to weigh down the film box lid...

Sevo
 
I've had film fogged by the luminous hands and numbers of my Seiko watch. Its not an old one with Radium, its about 15 years old. The hands and numbers glow in the dark after being exposed to light.
 
I had the almost the exact same thing happen the other day. I was loading a roll of tri-x when I noticed the numbers on my watch glowing in the dark. I didn't notice any effect on the film (I'll be taking my watch off in the future).

It got me wandering just how much light its take to fog film.
I remember my middle school dark room was pretty much just a closet with the windows painted black. Once your eyes adjusted, you could definitely see little cracks and chips in the paint where light leaked into the room. I don't think I ever had a problem with fogging though.
 
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