New lamps

[Dave Miller]

Are LED getting cheaper? Cheap enough to build a nice large enlarger head?

Yes.

[Dave Miller]

http://cosmos.bcst.yahoo.com/up/play...26723&src=news

Please excuse the darn commercial at the beginning, the Neurosuergon is brilliant, he also suffers from migraines.
CFL's give me headaches, and I get migraines too, it doesn't take a million euro, pound, or dollar study to tell me that the flicker rate caused headaches.

It's accepted that some CFL's cause problems for certain types of migraine, this is currently being discussed in the British press too. LED's are flicker free I believe, so should offer some relief, but no doubt will cause problems elsewhere.

[srs5694]

Are LED getting cheaper? Cheap enough to build a nice large enlarger head?

I've heard elsewhere that LED technology is improving rapidly, with improvements akin to those in the computer industry -- something analogous to Moore's Law applies to LEDs, resulting in an x-fold increase in light output every year. (I don't recall exactly what "x" is, but I think it's something around 2.)

I have links to a couple of LED enlarger projects:

http://www.huws.org.uk
http://www.trailing-edge.com/~shoppa/led.html

I'm sure others have experimented, too. I once tried fitting green and blue LED-based MR11 bulbs in my Philips PCS150, which uses three 35W MR11 halogen bulbs. The bulbs weren't bright enough to be practical, but my guess is that in another couple of years a drop-in MR11 LED bulb should do the trick for that enlarger; or perhaps a custom conversion could be done today, using a different design than the PCS150's standard configuration. Similar comments probably apply to more conventional enlargers. A "white" LED's spectral output is unlikely to match that of a tungsten bulb, so some adjustment of filtration will be necessary when using B&W VC papers or color papers. For the ambitious, using separate green and blue (and red for color work) bulbs should enable separate control of each bulb, thus obviating the need to use filters for contrast control or color balance. This sort of setup would require extra control circuitry, though.

Concerning the other issue mentioned in this thread's original post, lots of people (myself included) already use LED safelights. I've got a red E27-R24 bulb that fits a standard US socket. I removed the low-wattage tungsten bulb and filter from a standard safelight, screwed in the LED bulb, and all worked fine. The result is much brighter than the previous configuration and it passed my safelight tests, so I'm happy with this setup.

[Trevor Crone]

Thanks for the replies.

I already have a supply of 6, 15 watt pygmy lamps so should see me off this earthly plane

Again I've also stocked up on enlarger lamps; my Devere MG head takes 2, 300 watt halogens, so these would be more difficult to replace. I would have to hope for a suitable LED VC head.

With regard to safelights I think its about time I switched to an LED model. Although thinking about it I may install gas lights again

[roy]

One encouraging aspect of this discussion is that there seems to be a commitment to 'proper' printing in those few years ahead !

[Nick Zentena]

For the ambitious, using separate green and blue (and red for color work) bulbs should enable separate control of each bulb, thus obviating the need to use filters for contrast control or color balance. This sort of setup would require extra control circuitry, though.

I'd love a head big enough for 8x10 well 11x14 to be safe With a mix of blue and green. I don't need anything more complicated then on/off switches for each colour. Would work fine for split filtering.

I haven't looked in awhile but when I did even a 4x5 size head was still expensive using the 5watt leds. I think it was 5 watt.

[RH Designs]

I already have a supply of 6, 15 watt pygmy lamps so should see me off this earthly plane

It occurred to me in the kitchen last night that these lamps are also used in ovens and fridges, so I dare say they'll be around for some time to come.

[Trevor Crone]

One encouraging aspect of this discussion is that there seems to be a commitment to 'proper' printing in those few years ahead !

You bet! Death before dishonour!

[Dave Miller]

I think I recollect that the ban is for the larger sizes of tungsten lamps, 60 watt and above, I think. That doesn't mean that the smaller sizes will continue to be made; that depends on the market and economics of manufacture.

[bdial]

I think Dave has identified the real threat. Where specialty bulbs of various sorts might be allowed, the cost of those lamps may become quite high. Perhaps not so much with the low wattage bulbs we use in safelights, where they have common consumer use as well. Those are easy to substitute anyway.
My concern is with the enlarger lamps. Mine uses an 80 v 200 W MR16 bulb. I suspect that LED bulbs matching the output of high-wattage tungsten bulbs will get left behind. I'm certain that LED based bulbs for the odd voltages used in various enlargers/projectors will get left out.

The U.S. is starting to get on this "phase out tungsten" bandwagon, in some respects, I'm all for it, except in respect to this particular impact.
For household use, I am especially eager to see advancements and price drops for LED based lighting, as I can't stand CFL's. I've had several of them fail within a few weeks of purchase. If I follow the rules in my town, I have to pay hazardous waste fees to discard them, and my eyes don't like the fluorescent light color of the standard ones. Fortunately, they don't give me headaches though.