On Fri, 27 Sep 2013 14:34:59 +0100, N_Cook wrote:

Then I intend in the first instance to buy 5x 1.2W white LEDs, 3500K, 20
degree, for proof of concept. (...)

I've done this with marginal sucess. The problem is focus. The
original light has all the light coming from roughly a single point.
An array of 5 LED's will distribute the light over a much larger area.
It will work well with light from the central LED using the original
reflector, but the outer LED's will be wasted and splattered all over
the room.

You don't really need the original reflector if the light source has
its own forward facing reflector. Try cramming an MR16 bulb in place
of the projector bulb and reflector. The smaller size MR16 lamps
might fit.

Mo
http://www.instructables.com/answers/Change-a-projector-lamp-to-LED-/

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Jeff Liebermann
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