Since I use a red light very often during my back yard astronomy sessions, I have found a rear clickie light was most convenient to use for me. I wanted to use the SF L1 Red LED but it was far to much of a spot and too bright.
I took a Mini-mag filter accessory kit which fits the SF L1 perfectly, and sanded the clear filter to Diffuse the spot. I also added the cyan filter to dim the light further..
The filter also can be easily removed to return the light back to stock if needed.
The L1 + diffuser + cyan filter appears much brighter than the beamshots show. The camera settings were done at close to saturation for the L1 - No filter, so due to the dynamic range of the digital camera (20D), the L1 + diffuser + cyan filter shots look quite dim.
The Beamshots were ALL done using the L1 at LOW Intensity. I find this intensity works great for reading eyepiece values and maps.. I use the high intensity for walking near the telescope to avoid tripping on wires etc.
This Diffusing Filter works Great!
Beamshots were taken at about 2 ft distance, so the sanded filter scatters the light much more than would appear in the shots.
Here is the L1 with the filters next to it:
L1 with the filters attached:
(Camera settings are constant in the Beamshots)
L1 - No Filter:
L1 + sanded clear filter
L1 + sanded clear filter + cyan filter