Darkroom black paint

I am converting a small bedroom into a darkroom. I've put heavy duty

tinfoil and gaffers tape on the windows and I'm wondering if I need

to to paint the walls black. It seems like the light from the

enlarger will bounce off the walls and hit the photographic paper. Is

this bounced light a significant problem?

Hi Jon,

 

I don't know if light bounced around the room is a problem. However, over the years I have worked as a custom printer at two different pro labs. At both, all the darkrooms had walls that were painted a flat black.

In a lifetime of labwork, I never seen a black darkroom, amateur or pro, and I've both built and seen a LOT of them.

The general rule is: A darkroom should have WHITE walls.

 

The problem in a darkroom is the light entering the room. It will fog even if the walls are black, however black walls will make the darkroom light darker (and you will normally need all the light from that lamp).

 

See for example http://www.darkroomsource.com

If your enlarger leaks light from around the negative carrier and lamphouse, then you can paint the area behind the enlarger black. Certainly don't paint the whole room black. Try to cure the light leaks if any first.

Black darkrooms are hell to work in. It takes way too much safelight power to see anything, risking fogging of the paper. It's hard to evaluate prints under white light. Go with white or off-white and as the other post said, paint the area around the enlarger black if it leaks a lot of light. I've never seen a decent enlarger that leaked enough to make this important. (If I had a room devoted just to loading film in tanks, yes, that could be black.)

Agreeing to what has been said and Conrad's comments... it is also very depressing in a black room and you will tire faster than usual! I have never liked the black darkrooms. Mine at work is a white walled one and I have never had any problems with color or B/W!

Most commercial darkrooms are painted flat black,contrary to the advice given to you.Enlargers that leak light,are in need of repairs.A safelight should be so dim that you cannot see for a minute,untill your eyes adjust to it.Otherwise you are your fogging paper.You certainly can use a bedroom without painting it black,as long as all light leaks are taken care of.Im assuming you will be handling film in here also?After you have your windows & doors light sealed,sit in there a while and see if you can make any shapes.If after 10 minutes,you cannot see your hand in front of your face,the room is sufficiently dark.To test your safe light,place a sheet of photo paper on your enlarger's easel,cover half of it with a sheet of black paper.Let this sit for 5 minutes,then process normal.If the 2 sides arent the same,you have too much safelight!

I now have my darkroom in a spare bathroom. While I have black velvet hung over the bathroom mirrors to prevent reflection, the walls are white and I have no problem with paper fogging.

 

Here's a test. Expose a piece of paper under your enlarger for a few seconds without a negative in the carrier to break down its resistance to light. Then, with your safelight on cover half the sheet leaving the other half exposed to the safelight for a minute. (You may wish to repeat the test for two and three minutes, as well.) Then process the sheet for the normal developing times. If there is any difference between the densities of the two sides of the sheet, you are getting safelight fog. This test is better described by Ansel Adams in his essential work "The Print":

 

http://www.amazon.com/exec/obidos/ASIN/0821221876/qid=1008861928/sr=1-1/ref=sr_1_78_1/104-5738430-7044716

 

The bottom line is that the type, intensity and positioning of your safelight is far more important than the reflectivity of the walls. Precise adherence to safelight instructions contained in paper packs will do far more for you than black walls.

My cabinetry is all black Formica, but the walls are painted 18% black (flat surface) and I find it familiar, relaxing, and effective. My darkroom is small enough -- about 65 s.f. -- that I'd be reluctant to paint it white since even a tiny light leak can bounce around a small space quite a bit.

I've had darkrooms in 4 dwellings for a total of 20 years. All have

had white walls and have caused no problems at all. If you are

building a purpose built darkroom in a professional structure

then, sure, paint affected walls flat black. For an amateur

application it is overkill and does produce a dreary environment

for solving a tiny problem.

Having worked in both flat black commercial darkrooms and less permanent ones in gray to white, I vote for black. It's not mandatory but it removes one more variable - but then I use older enlargers, doing tray processing and film loading etc. where total blackness is desired. It's amazing all the little light leaks from vent shafts, sealed windows, LED displays etc.

Boy, I don't know where I've been all these years--out of the darkroom I guess. Back in the "old days" of orthochromatic film--you remember, that stuff that we used in 4x5 Speed Graphics and which also came in 120 roll film by Kodak as Super XX (before Tri-X)--we worked in darkrooms which were always painted WHITE! The white reflected the red safelight better and if there was any stray "white" light bouncing around, you sure knew it in a hurry. Even printing under a safelight was much better in a white darkroom because a 5-watt bulb generated a lot of "safe" color green/yellow light that bounced off the walls and gave you plenty of illumination to work but had no effect on the paper. We used to take a penny or a nickle and put it on an 8x10 sheet of printing paper for about three minutes, then develop the paper. If you could see where the coin had been sitting then you had too strong a safelight or too much extraneous light entering your darkroom. Certainly the 1950's and 1960s books by Kodak on "Darkroom Construction" recommended painting them white. Although it may be counter-intuitive to some, it makes common sense when you think about it. You don't wnat to have to depend on non-reflective "paint" to make your darkroom light tight. It won't help; you have to track down the source of the light an eliminate it.

Don't paint your darkroom black. Black darkrooms are misery to work in -- this said from experience -- as the safelight gets completely lost.

 

White walls are perfectly fine if you have no light leaks. If you DO have light leaks, fix them.

Thanks for responses.

 

My concern was not light leaking from the enlarger. I'm more worried about the following scenario.

 

1. turn enlarger on to expose paper.

2. the light travels through the negative, hits the paper and then is diffused around the room.

3. The diffused light hits the walls and is reflected back (diffusely) towards the paper.

 

The intensity of the reflected light hitting the paper may be 1/100th the intensity of the direct light from the enlarger, and so may not be an issue.

I'd say inverse square law applies - even assuming that the paper and baseboard (if you do not have a masking carrier) are perfect reflectors. You have a couple of feet, maybe four from negative to paper, and the walls and ceiling will be several times that (there and back).

 

Local low-reflectance around the enlarger can help keep any change in base fog level under control, but black craft paper or velvet would go a long way in a shared space.

 

My (permanent) space gets used for a lot of related work in white light, so I prefer white walls.

The walls of my darkroom are all painted matt white. And I use two safelights due to slight red-green colour blindness. I've never had a problem with paper fogging and I've tested up to thirty minutes. If your enlarger does leak white light then fix a large sheet of black paper on the wall behind the enlarger.

I followed a recommendation to paint my darkroom amber-yellow. It looks quite similar to white (it's very bright) under safelight and yet reflects only yellow if white light should hit it.

 

Of course the quarter test on a piece of photo paper is a great idea anytime you use a new darkroom, even if it's only new to you.