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How light tight for print making darkroom

hoffy

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Howdy,

I am nearly through the required tasks to get my darkroom ready for printing.

My question, for a darkroom that is going to be predominatly used for printing only (Film is loaded either in my wardrobe or a daylight bag), how light tight do I need to get the room?

Will the safelight mask any stray light that does make it through?

I have a few pin holes (literally) in my blockout curtain that is letting a bit of light in. Do I need to patch all of them?

Cheers
 
It's best to be totally light-tight, you could get sone acrylic black paint and paint over the pinholes, I know it works well because I used it to light proof a Thornton pPickard shutter as well as a Speed Graphic. It'll be absorbed by the material which remains totally flexible.

The paint is cheaper than a small number of ruined prints

Ian
 
good points made by Ian - but .... it's not as vital as it would be for film development. There's all kinds of leaks around my darkroom, none of them are obvious until I've been in there for about 10 minutes - as long as none of them shine directly (or reflect from other surfaces) onto where you will be handling, placing or developing the paper, it shouldn't be too much of a problem. This is all assuming they are not glaringly obvious when you turn out the lights of course!
 
Agreed...fully light-tight is best. It may seem that a pinhole of light is negligible and may not actually ruin prints, but any unwanted light (even a faulty or incorrect safelight) could potentially affect the quality of your work.

And, no, a safelight definitely has no effect in masking or cancelling-out any other light.
 
One point to bear in mind is that if the blackout material has developed pin-holes in 6 months to a year there will be many more

Ian
 
Ahhh, the pin holes are from my bad sewing skills! I went in there a few moments ago (its around 20:30 at the moment) and the pin holes are not noticable. The other side of the dark room I can see a lot of light getting through the door jam. I am deciding whether that side needs a curtain as well, or whether I can get away with some adhesive insertion foam in the gap or all the house lights off (my dark room time is typically going to be after dark.).

Just waiting for the kids to go to bed, then all the lights are going out and I will sit and wait for half an hour or so (or until the Turkey GP starts!!!).

I do, though, think I need to consider some more permanent arrangements, especially if I want to work during the day. Hopefully this works as a good stop gap for now.
 
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I have often wondered if, instead of blackout material, using a red gel sheet over windows etc. would work for an enlarging only darkroom.
 
Less than you think it has to be. When I print color at my school I noticed that there is a fair amount of light filtering in from above. It's enough to actually see what you're doing once you're adjusted. I haven't had a any fogging problems, granted that I don't leave the paper out. Don't get too worked up about it.

EDIT paper is fairly slow. If you're loading film you want dark dark dark dark darkness. Other than that, if you can clearly see the paper that you're holding after a few minutes to adjust (20 maybe) I would consider blocking out more light. Then add a red safelight if you're doing B+W work.
 
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hoffy said:
Howdy, My question, for a darkroom that is going to be
predominatly used for printing only ... how light tight do
I need to get the room? Cheers
Click to expand...

I've a not very light tight darkroom. A piece of carpet blocks
the door bottom when film processing. Film is loaded behind
a counter partition and sees little light from other small
sources. Body blocking is used to shade the film while
loading. Exterior light levels are kept low.

For prints none of the above precautions are taken.
The paper is not left long emulsion side up. Dan
 
We recently had a series of threads about pro darkrooms from the 70s and 80s on filmwasters. Neil Slavin had red plastic windows in his - see here for details.
 
Well, I've just completed a 20min test with the lights out in both the room and the adjacent rooms...No problem. I forgot I had the proper blind, which I had taken down to get the curtain fitted. I put that in place and it has accounted for the pin holes. The only issue I had was light leaking through the Velcro (I am assuming it is not contacted 100 % in some spots) and a very dull amount of light under the door, both fixed with duct tape and a towel respectively.

Now, I am mighty annoyed......It won't be until next weekend when I can actually use it!

Cheers and thanks for your imput all!
 
Simple test that should be done from time to time. Even should be done to make sure your safe light will not be a problem. Take out a single sheet of paper and lay on the table where you would normally work, be it enlargments or cantact prints. Let it lay there with some objects on top (IE you grain focuser, or anything with a simple shape). Let it sit for about the longest amount of time you would expect a sheet to sit out while working on it. 10mins maybe. After the time is run out, develop it as normal and when in light, look for signs of the shapes on the paper at all. If the the paper is completely white, you are OK. Try it with safe light on and off to test for light leaks and/or to confirm you safe light is infact safe.

Jason
 
Wirelessly posted (BlackBerry9000/4.6.0.167 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/102 UP.Link/6.3.0.0.0)

I print in my darkroom (read: downstairs half bath) and I have light coming in at the bottom of the door. VERY LITTLE LIGHT. Of course my girth is planted between the bottom of the door and my working areas because right in front of the door is the only place for me to sit/stand.



All this to say I have had no adverse effects with paper fog due to this light. And I process film the same way. I would estimate a five minute time before I can make out any details in the gloom.



So in answer, yes. It must be light tight. Completely. But I don't practice what I preach.
 
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Dear Hoffy,

Just give it a try. I doubt a few pinholes will be a problem. Just make sure you only take out one sheet of paper at a time. ;>)

Neal Wydra
 
Leon said:
We recently had a series of threads about pro darkrooms from the 70s and 80s on filmwasters. Neil Slavin had red plastic windows in his - see here for details.
Click to expand...

Thanks for that Leon. Very interesting reading.
 
Try the black plastic sheeting sold in garden supplies or blackout material for curtains.
 
Instead of sewing and chancing pinholes, get a roll of "Stitch Witchery" an adhesive gauze tape which joins cloth when sandwiched between the pieces and heated by a common iron. It's similar to lacquer dry-mount sheets for backing prints.

Walmart carries this stuff and it's not expensive.

You can use it for patches as well.

Eli
 
My door is leaky and it doesn't seem to matter. I have tested it by exposing paper to various shades of grey and leaving it out with half of it covered. It doesn't fog at all up to 5 minutes so I figure that's all that matters.
 
Thanks guys!

I am now a happy chappy! Its all up and running and I have my first contact print drying!

Yes, there is some light and 100% block out is probably 95% blackout, but thanks to the blind setup in the room, it proves not to be much of an issue!

I have also lined the door into the rest of the house with a weather strip. There was a bit of heartache as I had to adjust the door latch so it would close, but all now seems fine.

I also did a few test strips, one with safelight off and another with the safelight on, both with the focus scope sitting on the strip (thanks for the tip!).

Couldn't see any noticeable fogging, so I am happy!

Cheers and thanks
 
I used dark red plexiglas over the 2 small windows in my bathroom darkroom. Even in full day light it is perfectly safe. Film can be loaded or processed at night. There are no street lights or neighbors close to where I live. The biggest problem is not bumping in to the Beseler 45. It takes up 1/4 of the bathroom.
 
I have my darkroom in my motorhome and regardless of how hard I try, there are still some minor light leaks...ie around near the edge of the window black out cloth, in the ceiling around the air conditioner vent and under the door. As long as I am just printing, I have never had a problem. I tend to make sure during development to place the image side down until I am ready to make a quick look to see how the print is looking.

I learned the hard way to not develop infrared film unless it is also dark outside. So all film development gets done once the sun sets.
 
In the first darkroom I ever worked in, it was hardly light tight. There were many pinholes through the black acrylic paint over the windows, some spots had black construction paper over it too but still..

One project was to cut a piece of paper and hold it against the window and move it slowly, then process it. I have a few spirogram-looking prints like that.

Otherwise, if you kept your paper away from the window you were fine.
 

This is always one of the better solutions, although, I would say double the time. If it's safe at 20 minutes, it will be safe at 10 minutes. You never know when something stupid will happen, that requires an unfixed print to stay in the dark longer then planned, like dropping the tongs on the floor when a print is in the stop......
 
Why, I wonder, has nobody mentioned the coin test? Lay a coin on a piece of unexposed paper and leave it for some length of time. Develop the paper and see if you can tell where the coin was resting. If so, you need more light proofing.
 
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