Brilliant White: safe for darkroom walls?

[JBrunner]

The colour of the wall is the colour the walls reflect!


Steve.

Not if they're black. Except black isn't a colour, I mean color. Oh hell, none more black.

 

[AgX]

Just checked all the white walls in house: no optical brighteners applied. Maybe the adding of brighteners is a more recent trend.

 

[Jonathan R]

AgX, how do you check? Here in the UK, everything sold as Brilliant White (as opposed to just White) has optical brighteners. (Strangely, it also fades to a very dirty looking yellowish-white as it ages.)

 

[AgX]

As said, make a check with a UV-lamp before buying. A simple miniature UV-TL tube as used for bank-note checking will be sufficient.
In case you should not know what to expect, just get into a darkened room with some common papers around, then you'll know what to look for at the paint dealer.

 

[cliveh]

As others have pointed out optical brighteners in paint are not a problem in a darkroom. As Steve mentioned it's the colour that white reflects.

 

[AgX]

Not quite true, it's about the colour that the wall reflects and emits.

In case you have not much UV-light, there will not be much blue emittance either.
But many darkrooms are used for lighted work too, as critical proof of prints, including colour prints. What would be the idea behind installing a high quality daylight-TL lighting when you add additional blue to the room, and the print to be examined.

Maybe this all is academic. But so might be this whole thread.

 

[cliveh]

Not quite true, it's about the colour that the wall reflects and emits.

In case you have not much UV-light, there will not be much blue emittance either.
But many darkrooms are used for lighted work too, as critical proof of prints, including colour prints. What would be the idea behind installing a high quality daylight-TL lighting when you add additional blue to the room, and the print to be examined.

Maybe this all is academic. But so might be this whole thread.

You may be correct, as I have never compared densitometry readings of prints produced in darkrooms painted with normal white paint and those painted with white containing optical brighteners. However, this is not at the top of my photographic priority list.

 

[DREW WILEY]

There are no "optical brighteners" in architectural wall paint, merely different qualities of white support pigment: titanium dioxide at the high end of reflectance, calcium carbonate in the middle, silica at the cheapie end, and more often, some kind of blend of these. None of them fluoresce. But the brighter the paint, the more any surrounding light contamination will get bounced around. And I really don't care who says what. You might get away with certain compromises making ordinary prints, but if you develop a relatively high-speed film in trays, you might get stung in the shadow values.

 

[Jeff Kubach]

I painted my walls clear so I wouldn't have to worry about this!

Jeff

 

[barzune]

My darkroom is red. ......

Seriously, would this not be the most efficient option? I've been using a red LED safelight bulb, with a pretty bandwidth of light.
My darkroom needs a good coat of paint, and I was considering going grey, as in the 18% greycard, in order to neutralize reflections but, if I went with full red, I should get close to 100% reflectance of the good (safe) light while reducing reflectance of unsafe wavelengths down to a minimum. All this assuming that I'm concentrating on B&W work. Any thoughts?

 

[Jonathan R]

Seriously, would this not be the most efficient option? I've been using a red LED safelight bulb, with a pretty bandwidth of light.
My darkroom needs a good coat of paint, and I was considering going grey, as in the 18% greycard, in order to neutralize reflections but, if I went with full red, I should get close to 100% reflectance of the good (safe) light while reducing reflectance of unsafe wavelengths down to a minimum. All this assuming that I'm concentrating on B&W work. Any thoughts?

But when you turn the white room lights on, everything will look red. I want to see my prints as black and white, not black and pink! I also think grey would be pretty gloomy under both safe and white lights.

 

[fotch]

For the same reason the inside of all cameras (that I have ever seen) are flat black, this would be my first choice. It would be easier, in my opinion, to add safelight light where needed, and not have to deal with stray light, than trying to reduce bounced or reflected light where not wanted. Viewing light also is easy to add.

If it is a dual purpose room, then the other use would rule this out. JMHO

 

[cowanw]

Barzune
You are absolutly correct. and if you hold prints in plain view of a white light the black and white print will reflect white light. Our brains accomadate any minor reflectance from walls. Whether you like the room colour when the white lights are on is up to you.

 

[cowanw]

But when you turn the white room lights on, everything will look red. I want to see my prints as black and white, not black and pink! I also think grey would be pretty gloomy under both safe and white lights.

You may welll have other rooms in your house with walls other than white. I bet items in the room look normal colour. People look like people in a blue room, not like smurfs.

 

[Roger Cole]

For the same reason the inside of all cameras (that I have ever seen) are flat black, this would be my first choice. It would be easier, in my opinion, to add safelight light where needed, and not have to deal with stray light, than trying to reduce bounced or reflected light where not wanted. Viewing light also is easy to add.

If it is a dual purpose room, then the other use would rule this out. JMHO

Not analogous. In a camera you are intentionally letting light in during the exposure. It's what makes the exposure. The flatter the better (especially for a few camera or other camera used with lenses that cover more than the bare minimum film size frame) as you don't want that bouncing around - i.e. flare. The analogous situation for a darkroom is the area right around the enlarger which we've all agreed can be black or dark if the enlarger leaks. Theoretically there is some analogous exposure risk in light reflected off the easel or baseboard, off walls, and then back but the level of this would be so low in comparison to the sensitivity of paper that it just wouldn't matter, unless maybe your darkroom is very, very tiny.

For film there is no analogous situation at all as there should be no light present to reflect.

 

[JBrunner]

There isn't any discernable pink cast to anything in my red and black darkroom. Its lit by lights, not lights pointed at the walls. Checking with my color meter, it rates around 3100k, no shift. Very close to the walls I can get it down to 2700 and some magenta showing.

 

[DREW WILEY]

Gzzorrkk! Loud colors would be distracting. Not my idea of any place to evaluate either black and
white prints or esp color ones, or be trying to subtly tone them. But then, I don't like music in the darkroom either. I don't know how Fred Picker managed to print with Bach and Beethoven. I personally got a gout attack from listening to Handl while watching Barry Lyndon and all those frumpy
Englishmen eating pheasant and drinking port.

 

[fotch]

Not analogous. In a camera you are intentionally letting light in during the exposure. It's what makes the exposure. The flatter the better (especially for a few camera or other camera used with lenses that cover more than the bare minimum film size frame) as you don't want that bouncing around - i.e. flare. The analogous situation for a darkroom is the area right around the enlarger which we've all agreed can be black or dark if the enlarger leaks. Theoretically there is some analogous exposure risk in light reflected off the easel or baseboard, off walls, and then back but the level of this would be so low in comparison to the sensitivity of paper that it just wouldn't matter, unless maybe your darkroom is very, very tiny.

For film there is no analogous situation at all as there should be no light present to reflect.

Good point Roger. The concern I would have, in developing film outside of a tank, such as tray or film hangers, would be a light leak that may have been overlooked. Or bulk loading film, loading sheet film holders, loading roll film reels. Also, working with color paper, which are not as sensitive as film. Black would be more fool proof, but, perhaps, overkill.

The one darkroom I built and painted flat black, I never got around to completing and using, and all my other darkrooms were converted rooms, used as is, meaning whatever was there before it became my darkroom, and I don't believe I ever had a problem, other than noticing the after glow of the florescent lights.

 

[DREW WILEY]

Even the luminous paint on an old-school Gralab timer will fog certain films in trays. So will red LED's.
I put timers below the sink, where the film can't even see them. And no light trap it totally light tight. Let your eyes adjust long enough, then look at the film swishing in the tray, and see if there is any perceptible reflection at all. All enlargers leak light somewhere around the carrier. Most are
quite bad in this respect. Your paper might not get fogged in typical circumstances, but what if you
are projecting an image onto film, say for an enlarged neg, dupe, or interneg? Whole new ballgame.
Black wall, black countertop, black everything. Even handling film can generate static in cold dry
weather if you don't know how to suppress it. My film room is behind a darkroom, which is behind
yet another one!

 

[Roger Cole]

Gzzorrkk! Loud colors would be distracting. Not my idea of any place to evaluate either black and
white prints or esp color ones, or be trying to subtly tone them. But then, I don't like music in the darkroom either. I don't know how Fred Picker managed to print with Bach and Beethoven. I personally got a gout attack from listening to Handl while watching Barry Lyndon and all those frumpy
Englishmen eating pheasant and drinking port.

I like jazz to print by myself, typically streaming WWOZ or occasionally a play list off the iPod ap of my iPhone. But I do like music when printing.

I also shine my safelights off the walls, on purpose. You just have to test.

I understand Drew's point, but when I load film holders or developing tanks I turn the dial toward the wall (which is currently black until I get the real darkroom built - hanging black plastic as I mentioned) and I have no LEDs on. I develop in daylight Jobo tanks so no worries there. When I used deep tanks I used a countdown to beep timer that's not illuminated, but though I still have the tanks and thought about using them with Diafine, I haven't used them in years. So yeah, when I'm working with film that's different, and I work accordingly.

 

[dorff]

This is probably just a stupid question, but I guess it's best to be sure. I'm just about to paint the walls of my new darkroom. It occurs to me that Brilliant White contains optical brighteners. As far as I understand, these are basically fluorescent materials that absorb energy at UV wavelengths and re-emit it within the visible range of wavelengths. Since amber/red safelights are at the other end of the visible spectrum, can I safely assume that these optical brighteners are 'safe' in a darkroom?

Fluorescence always works down the frequency ladder (i.e. from higher to lower energy). UV can cause visible light fluorescence, visible light can cause infrared fluorescence etc. But not the other way round. There is no danger of red or green light becoming blue or UV in fluorescence. Since fluorescence is a quantum process, the energy state cannot be raised. Hope that puts your mind at ease.

 

[michael stevens]

Presumably if your darkroom was painted red you wouldn't need safelights at all. As long as all the light was being bounced off the walls and none spilled directly from the lamps.

 

[barzune]

Presumably if your darkroom was painted red you wouldn't need safelights at all. As long as all the light was being bounced off the walls and none spilled directly from the lamps.

I would think that paint surface, even a full, deep red colour, would reflect much broader wavelengths than just the red that we think we see. Even a red filter ( not a Kodak or similar safelight filter) over a standard lightbulb (with the possible exception of rubylith) probably transmits plenty of other wavelengths, and is not really all that safe for much more than a few minutes' exposure.

 

[michael stevens]

Try that and tell us how it works out for you.

I just need the right colour paint!

 

[DREW WILEY]

Red paint still contains quite a bit of white pigment, otherwise you'd need about twelve coats of the
stuff. It's not pure color by any means. But the idea would never work anyway.