Will a fire alarm light fog film?

[cablerelease]

Would the small green light from a fire alarm (on the ceiling) or the small flashing green lights on a wireless router cause film to be fogged when loading my film at home? Yes, I can cover them up but just curious if I can avoid pulling the ladder out. Thanks.

[Drew Wiley]

Quite possibly. It doesn't take much.

[Jody_S]

If you stand with your back to the fire alarm thing on the ceiling, so you're blocking the direct path for the light, you're probably safe for the few seconds it takes to pull a sheet out of a box and load it in a holder.

[Bob Salomon]

Take a sheet of film out of the box with that light covered. Put a quarter on the film and uncover the light. Leave it uncovered for 15 minutes. Cover the light and develop the sheet of film.
Do you see the quarter on the film? If so it fogs.

[robshepherd]

Take a sheet of film out of the box

I like that! Unless he's shooting 12x20... Just kidding!

[cablerelease]

Take a sheet of film out of the box with that light covered. Put a quarter on the film and uncover the light. Leave it uncovered for 15 minutes. Cover the light and develop the sheet of film.
Do you see the quarter on the film? If so it fogs.

Great idea. I just loaded my first 8 sheets of film in about 12 years. I think I'm going to reserve the last sheet of this box of 10 to run this experiment before I send out my first run to get developed. Even after trying to cover the fire alarm with gaff tape, there was a bit of spill coming through the crack between the unit and ceiling. If this does in fact cause fogging I'll have to just yank the battery when I load next time. Thanks everyone.

[LabRat]

The commercial building strobe type will when alarm is tripped...

Don't ask me how I know... ;-(

Steve K

[Louie Powell]

Two profound responses here:

Drew Wiley: "Quite possibly. It doesn't take much. "

Bob Salomon: "Take a sheet of film out of the box with that light covered. Put a quarter on the film and uncover the light. Leave it uncovered for 15 minutes. Cover the light and develop the sheet of film. Do you see the quarter on the film? If so it fogs. "


The key is that this is something an answer cannot be generalized. Years ago, some photographers used a green safelight to determine when a negative had received sufficient development. But the safety of that process depended on using the proper wavelight of light (green safelight filter), proper intensity, separation between the negative and the light, etc. Those were factors that could be set once in a darkroom, and then didn't change over time.

But in this instance, we don't know any of those factors. So the safe way to proceed is to conduct a test to determine if those light sources will fog the film, and then understand that the conclusion reached from those tests apply ONLY in the specific darkroom where the tests were conducted, and only as long as nothing changes.

[Bob Salomon]

Great idea. I just loaded my first 8 sheets of film in about 12 years. I think I'm going to reserve the last sheet of this box of 10 to run this experiment before I send out my first run to get developed. Even after trying to cover the fire alarm with gaff tape, there was a bit of spill coming through the crack between the unit and ceiling. If this does in fact cause fogging I'll have to just yank the battery when I load next time. Thanks everyone.

Why not put strips of Velcro Around the alarm and make a small box to fit around it? When ready to process stick the box up. When finished, pull it down.

[cablerelease]

Why not put strips of Velcro Around the alarm and make a small box to fit around it? When ready to process stick the box up. When finished, pull it down.

Yes, Bob, I am already thinking about some sort of system like you've described if I determine that the little bit of spill is, in fact, fogging my film.


The key is that this is something an answer cannot be generalized. Years ago, some photographers used a green safelight to determine when a negative had received sufficient development. But the safety of that process depended on using the proper wavelight of light (green safelight filter), proper intensity, separation between the negative and the light, etc. Those were factors that could be set once in a darkroom, and then didn't change over time.

Yes, Louie, I agree that I simply need to do a test. The main reason why I asked is I thought it was possible because the light was green it might not be an issue... but as you have mentioned I have no idea what wavelength, etc. this tiny green light is emitting.

[LabRat]

If in doubt, some tiny piece of black artist's tape over questionable area does wonders...

Another modern annoyance is smartphone, iPods, etc even if off... Had a dark charging iPod off while loading film, but when charged, it lit up to remind me it charged... Fone calls while dark can be an issue...

But really, smart handling of materials while loading does help... Not leaving film or paper potentially exposed to light, dust, moisture etc when handling will help by always leaving covered in black bags, boxes, holders and keep the process moving... Limiting potential exposure to these elements is your best bet...

Steve K

[Doremus Scudder]

You know, by now you could have got the ladder out and...

Just sayin'...

Doremus

[Gord Robinson]

When I go into the darkroom for a work session I ditch the smartphone or at least throw a towel over it so if it rings it won't light up the darkroom and get rid of any FitBit or the like athletic watch (not that I am any where close to being an athlete) but they tend to know to light up when you are loading film.