How light tight does a darkroom need to be?

[Ken Nadvornick]

I absolutely despise using changing bags. I would strongly suggest avoiding them, if you can.

Agree 100%. Tried spooling inside one once. Never again. It was the reason I took an afternoon or two to create sensory-depravation. Second best thing I ever did to the darkroom. Clean, cool, open, spacious, and reliable darkness is a joy to work in.

I do still have the bag for emergency situations on the road. But I've never needed it for that.

But I also realize that everyone's else's MMV...

Ken

 

[MattKing]

It is probably relevant to know that both Ken and I are both domiciled on the Wet Coast, in the Pacific Northwest.

Humidity does play a role .

 

[pentaxuser]

It was the reason I took an afternoon or two to create sensory-depravation. Second best thing I ever did to the darkroom.

Ken

Was Angela Lansbury able to persuade you to assassinate the President after a couple of afternoons in the darkroom?

Just kidding

pentaxuser

 

[DREW WILEY]

I paint darkrooms as BLACK as possible. For many things, exp any kind of color film or paper, you cannot use safelights. And the blacker surfaces are, the more likelihood they'll aborb any little light leak entering either from the outside or from some other source like an LED
timer panel. I learned all this the hard way.

 

[grahamp]

One way to reduce the risk in film handling if the room is nearly dark enough is to get a decent sized cardboard box, spray paint the inside black, leave one side open, and wear dark clothes. The box and you will cut out most extraneous light and reduce reflections. Less trouble than a changing bag. The usual dust precautions still apply, naturally.

 

[GKC]

The night is your friend. Do your darkroom work at night.

 

[cliveh]

Not sure if this is the right forum but I've been working on ways to temporarily light proof my bathroom and seem to have the window sorted but there's a bit of light coming around the door frame edges and through the ceiling exhaust fan. However, while I can see that light, I can't see a black notebook on a white piece of paper after 5 minutes (rule of thumb according to a kodak leaflet I found online), even when trying to it within about half a metre of them. Is this okay or do I need to block them off completely too? I'm wanting it dark enough for loading film into a developing tank as well as printing.

The door shouldn't be too bad as I can buy some fabric and removable sticky hooks to make a curtain if necessary, but I would like the fan so I can have it running.

Exposure = intensity X time. So if you have light leaks and you are quick at what you are doing, you may be OK.

 

[M Carter]

I'm using a converted kitchen (we own a duplex turned into one house and the kitchen will **someday** be a master bath... all the appliances are torn out.)

I bought a blackout window curtain on eBay, dark blue with blackout material, about 7' high. I put up a curtain rod for it, and then stapled some black felt above the rod, so it hangs over the seam above the rod. Works great.

 

[DREW WILEY]

Sometimes you can find true black rubber backed AV drapes, and they still have potential lint issues. A thick flock-backed premium studio fabric also blocks light, and can be cut to size from rolls. My method back in my medieval bedroom/darkroom days was to make a fitted removable plywood insert for the window with rubber weatherstrip around the perimeter. The bedroom door still has the black felt weatherstripping I placed around it - which now serves to block out noise when the TV is too loud in the adjacent living room!

 

[Doremus Scudder]

Sometimes you can find true black rubber backed AV drapes, and they still have potential lint issues. A thick flock-backed premium studio fabric also blocks light, and can be cut to size from rolls. My method back in my medieval bedroom/darkroom days was to make a fitted removable plywood insert for the window with rubber weatherstrip around the perimeter. The bedroom door still has the black felt weatherstripping I placed around it - which now serves to block out noise when the TV is too loud in the adjacent living room!

Exactly what I used to do when working in a converted bathroom: A plywood insert with two handles on it that just fit in the window and then a rolling blind to pull down over the whole thing. Weatherstripping and an adhesive threshold for the doors. It's really not to hard to get things really, really dark. Just stand in the dark for 20 minutes and then start looking for and fixing light leaks. Pretty soon, things will be more than dark enough.

Doremus

 

[largeformat pat]

You can get covers for ceiling fans, they have two flaps that rest over the fan when turned off. When the fan is on the flaps lift to ventilate, I used these on my bathroom, it worked very well. the other good thing is it stops dust and heat and cold to a degree too.

 

[Ghostman]

I'm surprised that nobody has mentioned the Inverse Square Law which states, for light, that

The intensity (or illuminance or irradiance) of light or other linear waves radiating from a point source (energy per unit of area perpendicular to the source) is inversely proportional to the square of the distance from the source; so an object (of the same size) twice as far away, receives only one-quarter the energy (in the same time period).

So the light seeping through the crack in the door, depending on how far your work surface is, probably doesn't stand much of a chance of being too destructive.

Our darkrooms should be as dark as possible, naturally, and I'm not saying that you shouldn't do a fog test, but if you can see the light coming in under the door don't panic.