Projection lamps

[P3D Allan Woods <allanwx@xxxxxxxxxx>]

I had been thinking (strange experience - though comfortingly
unproductive) about projection lamps...

There seem to be so many different designs.  I was wondering
how to get a "real life" comparison based on "performance."

What this means is, wattage doesn't directly correlate to light
output.

Lumens are not given for lamps with an incorporated relector.

Color temperature is quantitative - but what effect does it have
on perceived brightness?

How do 12V, 24V, 120V lamps differ (other than they require different
operating voltages and consequently, current flow) ?

Why pick one over another?

If bare bulbs emit light in (almost) all directions, does a bulb
with a built-in reflector emit twice as much light to one side
than if it had no reflector?

Are lumens really a measure of effective projection power?

Another frame of reference is: If you were going to make a projector
from scratch, how would you choose a light source? (...other than
cost, broad availability, transformer requirements, etc...)  ...or
are those too many restrictions?

If you have any answers, feel free to include any of the above
exclusions in your response...

Is it time for medication again?
Am I whining?
Should I forgive "volunteers" for all their oversights?

allanwx@xxxxxxxxxx


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