Omega D2 LED conversion

[vedmak]

I have read many old threads about the LED conversion, recently I was 7W and 10W LEDs offered at Mouser.com and digikey.com, did anyone try to use these for the enlarging purposes? I would be interested in some feedback if you guys did, before ordering.

 

[Kilgallb]

Hmmm. Have you tried the more simple LED light bulb. Works like a charm on mine. Only split grade printing though.

Find one with a frosted globe and no printing on the lamp.

 

[albada]

I have read many old threads about the LED conversion, recently I was 7W and 10W LEDs offered at Mouser.com and digikey.com, did anyone try to use these for the enlarging purposes? I would be interested in some feedback if you guys did, before ordering.

I don't know which products were on sale that you mentioned above, but I copied Mal Paso's design with great results. His posting (and my follow-up postings) are in this thread:
https://www.photrio.com/forum/threads/led-split-printing-enlarger-lamphouse.173834/

I am printing various kinds of photos with this LED-head as a way of testing it in a variety of conditions. Then I plan to add to the above thread (or start a new thread) with my final design. Although the BuckBlocks allow analog dimming (using potentiometers) down to under 10%, I built a 25% PWM circuit in order to dim by 2 stops more. That was necessary to achieve low contrasts. Grade 0 was the most difficult because it needs very little blue light -- less than what a BuckBlock alone could dim to. (Grade 00 was easy: give it only green light). However, PWM is not needed for split-grade work (which I recommend).

Here are the part-numbers for the LEDs that both of us used:
CREEXTE-ROY-1 Royal Blue (1500 mA) (Consider using CREEXPE2-ROY-1 instead, but check voltage-range first)
CREEXPE2-GRN-1 Green (1000 mA)
CREEXPE2-RED-1 Red (1000 mA)

You can find them here:
https://www.ledsupply.com/leds/cree-xlamp-xp-e2-color-high-power-led-star

You can also buy the BuckBlock LED-drivers, and power-supply (24v, 50w) from LEDSupply.

Mark Overton