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N_Cook N_Cook is offline
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Default Converting a 200W discharge lamp video projector to LED

On 28/09/2013 22:08, Trevor Wilson wrote:
On 27/09/2013 11:34 PM, N_Cook wrote:




**What a waste of time and effort. The best LEDs are approximately
similar efficiency to that of halide lamps. As others have stated, the
big problem will be that you are substituting a compact light source
with a rather diffuse one. The optics are not designed for such use.


But the lamps used in video projectors are ,in effect, not compact. The
direct light path from the reasonably compact source is blocked by an
electrode and non optical structural glass lump, relying on the mirror
surface of the light tunnel / light pipe to average out/balance-up the
light coming in at all sorts of angles, off the parabaloid reflector