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Switch for white light.

ac12

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Since a few people are building darkrooms, I thought I would make this comment, since I've seen problems here.

The switch for the WHITE light should be separate and difficult to accidentally turn on, for obvious reasons.

I've seen switches where the safelight and the white light switches are side by side in a double switch panel. And there was no protective cover over the white light switch. To me, that is an accident waiting to happen.

When I built my darkroom, I had the safelight switch at about chest level (where it was easy for me to turn on/off), and the white light above my head (where I had to reach up to the switch). This made it almost impossible to "accidentally" turn on the white light. The "almost" came when I had a friend over, and he was about 1ft-6in taller than me. HE could accidentally turn on the white light.

I had to turn OFF the safelight, as even with a small 7-1/2 watt bulb (smallest that I could find at the time), the 2 safelights were sometimes too bright to focus the enlarger. The WHITE walls, floor, and cabinet faces reflected the safelight quite well, and it was a BRIGHT darkroom.
 
Another approach would be installing a "safety" bump-on switch, but with a repainted button, not red.
You need to operate a release ring to disengage the automatic locking.
 
In the group darkroom I help administer, the white-light switch is behind a hinged cover that you must lift up to gain access.
In my own darkroom the main white lights are on a switch next to the safelight switch, but slightly harder to reach.
The other white light is on a switch that operates both the safelight and the regular light, so the white one is in a fixture with a pull-chain, which is a very effective arrangement.
 
My safelights are tied into the Analyser Pro, and have individual inline switches should I need to customize things (like a single deep red for Ortho). The white light is controlled by a pull cord in the middle of the room (it is a small space). I have no trouble finding the cord when I need it, but it is not noticeable moving around. It would probably drive a lot of people nuts

But no mistaking the switch. A mistake in intent, now that's another issue...
 
When I go to work printing in the darkroom the first thing I do is go around and turn on all my LED safe lights. From that point on the only lights I am turning on and off are the white lights. No real potential for an accident because there is no way to lean against the light switches. In my film processing room there is no safe light so no chance to confuse the light switches. I do have a pair of scissors with glow tape on the handle hanging on the wall and 3 feet away is the light switch with glow tape on it too. One is left hand operated and the other is right hand operated and I always remind myself not to absentmindedly hit the switch rather than grab the scissors.
 
Put tour safe-lights on a dimmer switch then you have full control.

I have my white lights on two switches, first I have a fluorescent tube on a normal light switch by the door, I also have two sets of spotlights (3 bulbs in each) on a pull cord this runs horizontally across the darkroom just above head height so I can switch these lights on and off from by the enlargers or by the sink. I have two bulbs angle to the 2nd fix and wash trays so I can check print densities etc easily.

During a printing session the fluorescent light is rarely used as they glow slightly after switching off. Here in the UK we are switching to LED lights so at some stage as prices drop I'll change this for an equivalent LED strip. The spotlights are tungsten halide but they do tend to need replacing so again these will be LED soon.

Ian
 
In the school darkroom I administer the safe light switches are at the normal height and the white light switches are about 2 feet higher, the only time this is a pain is when maintenance enters the darkroom and turns on the safelights first, does there thing and leaves the safelights on when they leave.

I like a bright darkroom and use a focus aid for printing, I rarely use an analyzer for black and white. So the safelights are not switched by the timer.
 
I like this.

I have a florescent on a separate switch, bright, used only for housekeeping. I have also had to deal with afterglow.

I have an incandescent lamp on a dimmer for print inspection "calibrated" for the dry downs of different papers, dry down is rarely a big issue with glossy RC papers but it can be a real issue with other papers. Some day I'll need to switch this for an LED, when it happens I'll need an LED that is compatible with a dimmer.

If forced to use LED's in safelights with dimmers, make sure your lamps are dimmable.
 
I mounted my safe light and white light switch Upside down one to another. When they are swept down the reds are on and white light is off; swept up the reds are off and the white is on.
 
Ian Grant said:
During a printing session the fluorescent light is rarely used as they glow slightly after switching off. Here in the UK we are switching to LED lights so at some stage as prices drop I'll change this for an equivalent LED strip.
Ian
Click to expand...

We use Cree LED-based replacements in some home incandescent sockets and I've noticed an afterglow. We also have an LED-strip fixture used under a kitchen counter which also glows. Like fluorescent lights, at least some (all?) white LED lamps use phosphors, which explains this. I don't know whether LED lamps are better or worse than fluorescents in this regard as I haven't needed to do any testing. Like others here my darkroom has a fluorescent fixture used only for housekeeping - print viewing is via a small 30W spot at appropriate distance, and my safelights are a mix of red incandescent and red LED.
 
You can buy switch covers that will prevent accidental turnons. Seems like I paid US $2 for a package of three. I use them around the house for things that I usually don't want on. You have to come in on the side of the switch with one finger to get access. Just enough of a reminder. I've bought them from several different stores so most hardware of building supply stores should have them. Just remove the two screws on the plate, place the cover over the switch and replace the screws. Nothing could be simpler.
 
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In the university darkroom I took care of, all of the safe and white light switches were side-by-side in the various rooms. I covered the white light switch with one of these: http://www.garvinindustries.com/con...ps/thssr-100?gclid=CMed-6iildICFdCmaQodYnMLgw

Actually, I was cheap -- I just bought the usual galvy ones for less than 50 cents each. Just read Gerald's post -- the conduit straps work the same way.
 
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darkroommike said:
I like this.
Click to expand...

I first saw this in the late Peter Goldfield's workshop facility darkroom in the late 1980's, you need the white light on a pull cord anyway fro safety with wet hands even with gloves on. Peter had assisted minor White for a while.



LED lighting is improving very rapidly, they seems to be better and a greater range every time I buy bulbs/lamps now. The problem at the moment is there's too many types of lamp bulbs.



I just checked quite a powerful LED light and it had no after glow so they must vary.

Ian
 
Accidents do indeed happen. When I was 16 years old I took a job at a local photo studio/lab. One of my first assignments was to process about 20 sheets of 4x5 B&W film. There was no lock on the darkroom door and the owner was not accustomed to having others around. So he forgot I was in the darkroom and opened the door while the film was in the developer. I threw my torso over the tanks and yelled, "DARK!!", after which the door slammed shut and I heard, "SORRY!!". The film didn't show significant signs of fog so I guess I was fast enough to block most of the light.

So yeah, I'd have something over the light switch to prevent accidents.

Does anyone remember the scene in the movie "Apollo 13" in which Kevin Bacon taped over a switch to remind him not to flip it while his colleagues were in the other capsule, which would have killed them both?
 
cowanw said:
I mounted my safe light and white light switch Upside down one to another. When they are swept down the reds are on and white light is off; swept up the reds are off and the white is on.
Click to expand...
As a Brit in California, *all* the light switches are the wrong way up! Parenthetically, I have a modern luminous clock in the darkroom, and I have to cover it when loading film. It is brighter than the old Gralab.
 
As far as the safe lights being too bright to focus the enlarger = most timers have a plug for a safe light that turns it off when the enlarger is on. I wired my over the enlarger safe light with a plug for that purpose. Works great!
 
Ian,
Good idea about the dimmer on the safelight circuit. I did not think of that when I built the darkroom. That may have solved some of the too bright safelight problem.

Now many years/decades later, when I move back to the house, I plan to rewire the darkroom safelight circuit. The safelight circuit will be changed from a 1 switch circuit to a 2 switch circuit, so that I can kill the darkroom safelights from the enlarger position also. It was a hassle to get up and go to the other end of the darkroom to turn off the safelights. I had a small safelight connected to the timer, so I could find my way back to the enlarger.

Oops, I just thought of a complication, I plan to put a 2nd enlarger in the darkroom. So where to put the 2nd darkroom safelight switch? I guess I will just have to get up off the stool and walk 2 steps to the nearest of the 2 switches.

Hmm good idea guys. I never thought of putting a small spotlight on a pull chain switch to check the prints in the fixer. Though as Mike mentioned, I may have to put a dimmer inline with the spotlight to get the light level down to a more appropriate level.
 
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Instant turn off may not be true for all LED bulbs. Some are coated with phosphors to control the color temperature of the light. This may prevent the light from stopping immediately after the current is shut off. Best to test.
 
bsdunek said:
As far as the safe lights being too bright to focus the enlarger = most timers have a plug for a safe light that turns it off when the enlarger is on. I wired my over the enlarger safe light with a plug for that purpose. Works great!
Click to expand...

hmm, something to think about, but it is the 2 darkroom safelights over the counter/sink that I had problems with. In a WHITE darkroom, that light really bounced all over the darkroom. I had no dark corners. A WHITE darkroom has its pros and cons, and that one con is that it can actually be too bright, at the enlarger. I need to try flat black paint around the enlarger. I did have a small safelight over the enlarger for when I turned off the darkroom safelights.

I could rewire the darkroom safelight circuit to control the darkroom safelights from the enlarger.
However, it will get more complicated with the 2nd enlarger that I plan to put into the darkroom. That would require a control relay circuit, with inputs from both timers, each controlling a relay to open/close the darkroom safelight circuit.
 
Two light switches: one is next to my enlarger and the other is the inspection light over my sink. I don't have any safety on my light switches. What I do have is the habit of glancing at the paper safe to make sure it's closed before I hit the lights.
 
You could get Amazon's Echo or Echo Dot, then a compatible 'smartbulb' for the white light; then turn on/off white light only via voice control.
Stupid/unaware roommates or SO's would not be able to switch on room lights by simply flicking on the switch...the bulb itself would have been turned off by voice control. And only you know the name that has been assigned to the darkroom white light for turning it on/off!
 
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This reminds me of the platinum printer who was tearing his hair out for weeks trying to figure out where the rust particles were coming from that were contaminating most of his prints. Then one day he pulled on the chain and the light went on! The chain to the light bulb had gotten a little rusty and dropped small specks of rust every time he pulled it.
 
cowanw said:
I mounted my safe light and white light switch Upside down one to another. When they are swept down the reds are on and white light is off; swept up the reds are off and the white is on.
Click to expand...
now thats an excelent idea!
 
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