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looking for red led bulb in europe..

chris77

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hello apug!

as i have seen in another thread people start using basic e27 led bulbs in the darkroom.
rather cheap and longlasting - yet bright.

i am having difficulties to find recommendations for such bulbs over here in europe.
so far i have been looking around amazonia and cannot find anything about nm or graphs..

can someone point out a good and simple bulb that works well?
thanks

chris
 
thanks for your reply, but i am actually looking for LED bulbs..
 
I think I bought this one at our local electronics store in The Netherlands (Groningen to be exact):
Dead Link Removed

I think you can also find these party bulbs in diy stores.

I've been using it for a few years now. No fogging as far as I can see.

Regards

Jan Alwin de Jong
 

well thank youor the link!
gonna buy something similar and test it..
 
I bought an Osram Parathom from an online dealer...
Osram 42139B1 Parathom LED Classic P, E27 80092-01 LED Bulb.
Be careful, the reds have also a slight orange cast, I found out while working with ortho-film, wich fogged severly. Multigradepaper seems to work, but I didn't do proper safelight tests, and 'I found fogging when I deposited some paper in 20cm distance for 1 minute.
 
thanks..
good to know more.. still gathering information-----
 
_*_ said:
thanks for your reply, but i am actually looking for LED bulbs..
Click to expand...

But why going into the hassle of finding an apt one spectra-wise, when incandescant darkroom lamps are still around?
Concerning the energy balance of a household that one darkroom bulb should be the least to bother about.

Or am I missing a point? Longevity?
 

I take it that there are safe red LEDs in the bulb mentioned. If so I can think of two possible advantages.
1. Presumably there is no need for the safelight red filter which can wear out, making the incandescent bulb unsafe and of course no need to buy expensive secondhand safelight cases

2. If these LED bulbs give a brighter light than the 15W incandescent bulb behind a red filter while being just as safe then this is a significant improvement over the 15W incandescent bulb. I'd love to have a bright light in my darkroom as long as it didn't fog my paper.

Both of the above points are based on my assumptions which might be wrong.

I agree that the electricity savings are quite small although at 0.65W compared to 15W the savings would mount up over say 2-3 years use in a darkroom

pentaxuser
 
well..
its not the electricity bill.
15w incandescent bulbs cost 3 times as much and i am often in a situation where i want to move them around - they are rather fragile.
and when you are working with emulsion coating and things like that - every lumen more can be pretty useful as well..
 
How about this? Dead Link Removed

It will take a little work to wire it up but it is "Photo Red" (670nm) from Cree and it is 3.5W. Another similar emitter (740nm) is 210 lumens so this should be plenty bright.

Edit: Or this:Dead Link Removed

It is a MR16 (bi-pin) bulb that you should be able to get a socket for relatively easily. 625nm
 
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interesting..
thanks.

still prefer to try some ready made bulb and test for safety
 
I went to the local electrical contractors looking for 95mm and 120mm diameter opal bulbs for an old enlarger and bought a couple of red LED bulbs at the same time. It will be interesting to see whether they pass a safelight test, or whether a different brand might be required. Any electrical shop will either have some sort of red LED lamps in stock, or have them available within a couple of days - there is no need to order online.

Going by a brand-name might not be as certain as one might think, as many of the importers buy bulk products (probably from China) and have them put in to their own branded packaging so what turns up in one batch may not be the same as the next, after all they are just red lamps for amusement-arcades, shop-displays etc. and don't require a detailed specification for that role.
 
_*_ said:
interesting..
thanks.

still prefer to try some ready made bulb and test for safety
Click to expand...

The MR16 bulbs are frequently used in track lighting. Imagine the possibility of having 1 track and directing light anywhere you wanted in the darkroom!?!?

Edit: Oops, just saw that the minimum order from Mouser is 10k for that particular bulb.
 
if you want really good LED based darkroom lamp, please contact me directly. I have bought professional lamp - 100% percent safe - tested against most MG paper types, yet very bright. The thing is not cheap, but worth it for sure!
 
I'd be interested to hear how you get on sourcing these LEDs. I've been thinking about trying some for a while after looking for some white ones to use in a home made light box. There are loads of these bulbs advertised on eBay.

Which is the best (I.e. Widest) wavelength band that will make them safe for most paper, and particularly Ilford?

I found this: http://www.ilfordphoto.com/webfiles/2011427111757603.pdf

Looking at the data for the SL1 filter, does that mean an LED would be paper safe if it emitted light between 600 and 700nm?
 
If my above post is correct, it looks like there are options on eBay. A trader in Hong Kong is selling ten 700nm bulbs (40lm) for £2.19 including postage! You would need a power adapter and 12 volt transformer, but it looks like it would be possible to DIY something for relatively low cost.

I guess the question is how wide is the spectrum emitted by these LEDs? I'm fairly sure they emit a very narrow bandwidth. Can anyone confirm?
 
Add a sheet of rubylith to a red LED bulb and you may have what you need.
 
MattKing said:
Add a sheet of rubylith to a red LED bulb and you may have what you need.
Click to expand...

Do you reckon you would need that in addition to the bulb being a 700nm one? Or is that a 'belt and braces' suggestion?
 
FujiLove said:
Do you reckon you would need that in addition to the bulb being a 700nm one? Or is that a 'belt and braces' suggestion?
Click to expand...

Many of these lamps have small "spikes" of blue and green emission. So while they are predominantly within the emission spectrum promised, there are bits of fogging light as well.

You can do a rough check for them using a CD and carefully viewing how light reflects off of the surface. As you move the CD you will see diffraction patterns - if there are blue and green bits, you will know you need the rubylith.

It is, of course, also necessary to do a full safe-light test: http://wwwca.kodak.com/global/en/consumer/products/techInfo/k4/k4TestSafelite.shtml
 
MattKing said:
You can do a rough check for them using a CD and carefully viewing how light reflects off of the surface. As you move the CD you will see diffraction patterns - if there are blue and green bits, you will know you need the rubylith.
Click to expand...
Wow man, that's cool didn't know of this And yes, my parathom seems to have a slight yellow cast under some angles, so not that safe for Multigrade. But I'm working with it for some months now and it does the job for me so why bother anyway?
 
grussmir said:
my parathom seems to have a slight yellow cast under some angles, so not that safe for Multigrade
Click to expand...
Most paper isn't really sensitive to yellow. It is sensitive to blue and green.

Yellow filtration is used to reduce or eliminate blue.

Magenta filtration is used to reduce or eliminate green.
 
great stuff.. thanks everybody!
 
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