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Pete Oakley
17-Feb-2016, 17:03
At the moment my darkroom is illuminated by a couple of low wattage incandescent bulbs, and they are safe when they are turned off unlike florescent bulbs and tubes. As incandescent bulbs are gradually being banned in the EEC would LED bulbs be safe in the darkroom when they turned off.
Pete.

Jac@stafford.net
17-Feb-2016, 17:10
IMHO, LED safe-lights are a waste of effort and time. Of course they will be extinguished when turned off.

Incandescent bulbs will always be available, especially as MIT has introduced an incandescent equal in energy conservation as LEDs to the embarrassment of the government.

vinny
17-Feb-2016, 17:14
He's not asking about safelights.

Household Led bulbs do glow briefly after turning them off. It shouldn't be an issue though.

Geary Lyons
17-Feb-2016, 17:14
I use LED lights in the overhead sockets no issues. IMO, LED safelights are hardly a waste of time. Incandescent bulbs are a waste of energy. I have been using a DIY red LED safelight, that I can dim with a PWM based switch, for about 8 years. It is connected to my enlarging timer or straight through. I have fog tested it and used it for paper and ortho film without a problem. The great thing about true single color LED's is the very narrow color spectrum. It can be used pretty bright without fogging. Very handy for cutting down the x-ray film.

Of Course, YMMV!

Cheers,
Geary

Greg
17-Feb-2016, 17:42
FYI sidebar: My red incandescent safelight bulb wasn't working so I plugged in a red compact fluorescent bulb. Processed my ortho X-Ray film and it was fogged.

Have read of several photographers installing IR LEDs in the ceiling of their darkroom. Turn them on and donning a night vision scope you can essentially "see in the dark". I believe workers at Kodak were the first ones to do this back when.

Pete Oakley
18-Feb-2016, 03:20
Thanks for your help, I'll use a couple of ordinary LED's with confidence. Jac, I just want to hang a couple of bulbs, that will be safe when they are turned off, on my darkroom ceiling. The MIT is very clever but the price would need to be competitive before I even considered using them. I know that I'm on the dark continent of Europe but I had heard of this development.
Thanks' again,
Pete.

jp
18-Feb-2016, 05:23
Pete, use the search feature to look for led safelight discussions here. There are parts and URLs referenced for easy ordering. I use them.

I visited UK Midlands area last year and loved the area! Visited JLR at Honiley airfield.

jose angel
18-Feb-2016, 07:22
I have been using LED bulbs on my darkroom for some years now (enlargers, safe lamps, etc.). In my experience, LED bulbs (quality ones) are just much better than incandescent ones for almost everything.
To my taste, energy saving lamps (cold cathode) are simply unusable for photographic purposes. LEDs are another topic.
I have seen LED bulbs glowing after switching them off; in that cases it was an installation issue, not a bulb problem. Use the proper switch.

bigdog
18-Feb-2016, 17:34
I've switched out all white lights in my darkroom to led, mainly to stop the heat generation (I'm in Texas). My filtered safelights are all still incandescent, but they are, of course, such low wattage that it is not that big of a deal. As the safelight bulbs burn out, I will switch to led, but since led became commonplace, no burn outs. I do have some red led safelights, in addition, but that's a whole other discussion.

vdonovan2000
3-Mar-2016, 17:20
I installed and have been testing one of these from Super Bright LEDs:
https://www.superbrightleds.com/moreinfo/aluminum-light-bars/lfd-series-led-linear-light-bar-fixture/1310/#/tab/Specifications
They really are bright, I bought two of the four-foot strips for my 10' x 10' darkroom, but really only need one.

Super Bright's specs show that the red version emits at 630nm, which I believe is right for variable contrast paper. I was told by Super Bright's customer rep that the LEDs are 335s, which emits a pretty narrow band, between 600 and 650nm:
http://www.snowdragonledhk.com/images/2013/id171/side-view-smd-335-led-red.pdf

Best of all, they've passed the Kodak test (https://www.kodak.com/global/en/consumer/products/techInfo/k4/k4TestSafelite.shtml) in my darkroom.

HMG
3-Mar-2016, 20:08
Incandescent bulbs will always be available, especially as MIT has introduced an incandescent equal in energy conservation as LEDs to the embarrassment of the government.

Silly. It was never an issue with incandescent bulbs, rather an issue with terribly inefficient bulbs.

To keep my post somewhat legal, these (https://www.superbrightleds.com/moreinfo/g-series-minature/2-watt-g11-globe-bulb-360-degree/440/#/tab/Specifications) in red have often been recommended.

Thad Gerheim
3-Mar-2016, 20:41
I'm all for LEDs, they emit no UV light which makes them great for alternative processes. I replaced about forty of them in my gallery, mainly to keep the temperature cooler, yes even in Stanley, ID the coldest place in the lower forty-eight it's now a concern, but it saves Salmon also! My electric mostly comes from hydro (DAMS).

Ian Gordon Bilson
3-Mar-2016, 21:00
I installed and have been testing one of these from Super Bright LEDs:
https://www.superbrightleds.com/moreinfo/aluminum-light-bars/lfd-series-led-linear-light-bar-fixture/1310/#/tab/Specifications
They really are bright, I bought two of the four-foot strips for my 10' x 10' darkroom, but really only need one.

Super Bright's specs show that the red version emits at 630nm, which I believe is right for variable contrast paper. I was told by Super Bright's customer rep that the LEDs are 335s, which emits a pretty narrow band, between 600 and 650nm:
http://www.snowdragonledhk.com/images/2013/id171/side-view-smd-335-led-red.pdf

Best of all, they've passed the Kodak test (https://www.kodak.com/global/en/consumer/products/techInfo/k4/k4TestSafelite.shtml) in my darkroom.

This make my heart "soar like an Eagle". Looking everywhere for led safelighting that runs on 230 volts - nada.
Now, 12v d/c I can do. Passing the Kodak test is just gravy.
If anyone can suggest viable alternatives to the above,please say.

Willie
4-Mar-2016, 07:19
mainly to keep the temperature cooler, yes even in Stanley, ID the coldest place in the lower forty-eight

Colder than International Falls, MN or Cutbank, MT?

HMG
4-Mar-2016, 07:22
This make my heart "soar like an Eagle". Looking everywhere for led safelighting that runs on 230 volts - nada.
Now, 12v d/c I can do. Passing the Kodak test is just gravy.
If anyone can suggest viable alternatives to the above,please say.

Check out the "boat / marine" offerings at superbrightleds

Thad Gerheim
4-Mar-2016, 08:16
mainly to keep the temperature cooler, yes even in Stanley, ID the coldest place in the lower forty-eight

Colder than International Falls, MN or Cutbank, MT?

Check the summertime lows. On average there is only about 30 days a year that are above freezing at nighttime. And they don't fall in a row, so it's mighty short growing season.

Sal Santamaura
4-Mar-2016, 10:28
...Looking everywhere for led safelighting that runs on 230 volts - nada...I have for years used the red version of these:


http://www.optiled.com/upload/products/optiledlightingfile1_65.pdf

They automatically detect and operate on whatever line (mains) voltage is presented, from 100 V to 240 V AC, and have narrow, precisely defined spectra. It appears that adapters from New Zealand's standard B22 bayonet sockets to the "Edison screw" base of these are readily available. I've properly tested red Festivals out to ten minutes on many graded and multigrade papers with no fogging.

It appears that Optiled might have discontinued those Festival lamps. This retailer


http://www.liveline.be/liveline/optiled/nodim/0000009a5b0ae6c24.php

seems to still have red ones in stock, although I'm not sure whether it sells outside the EU. I'd suggest ordering several if/while you can.

Randy Moe
4-Mar-2016, 10:41
Sal's suggestion follows my thinking last night.

It may be worth somebody with 220/240vac 50/60HZ to TEST the 120vac Red Led many in USA use. This one in RED only. (https://www.superbrightleds.com/moreinfo/led-globe/2-watt-g11-globe-bulb-360-degree/440/)

I notice many electrical devices now have the mentioned auto voltage selection feature, which only makes sense in our global markets.

Be very careful testing as it may act as a flash bulb, but I doubt it. I would put one in a shop light, do it outside and leave it on for a week, if I was doing the test. It will either blow or glow.

angusparker
4-Mar-2016, 11:29
I have for years used the red version of these:


http://www.optiled.com/upload/products/optiledlightingfile1_65.pdf

They automatically detect and operate on whatever line (mains) voltage is presented, from 100 V to 240 V AC, and have narrow, precisely defined spectra. It appears that adapters from New Zealand's standard B22 bayonet sockets to the "Edison screw" base of these are readily available. I've properly tested red Festivals out to ten minutes on many graded and multigrade papers with no fogging.

It appears that Optiled might have discontinued those Festival lamps. This retailer


http://www.liveline.be/liveline/optiled/nodim/0000009a5b0ae6c24.php

seems to still have red ones in stock, although I'm not sure whether it sells outside the EU. I'd suggest ordering several if/while you can.

+1 I use the same ones in my darkroom - no fogging, they are great.