Re: 1?? Mcd Xenon Flashlight Project - BFF
So I saw a comment on why I didn't do anything to reduce spill light. For instance I could have installed so called spill rings or just a tube over the lamp. Well, it would have been nice, but not really worth the effort because the BFF doesn't spill much at all, it just looks worse here because of the snow.
So I did a pretty interesting, if not "brutal" comparison tonight. I took the biggest LED thrower I have, which isn't very big at all(!) but still a great thrower for it's size, an Acebeam K50 v3, XHP35Hi, 450 Kcd, 2500 lm (on a good day?) vs the BFF. I set the camera to 1/30 sec, f/2.8, 15mm, ISO 1270 and took a few shots. The results speaks for themself. The K50 almost "outspill" the BFF, and in some places it does, seen on the trees to the right, 1/4 downrange
BFF, note that almost all the spill comes from the tungsten anode seen by the classic 2700K incan glow, not from the arc itself. The main reason for this is that the anode is not in focus (and never can be). But when this light is used on grass, gravel, not to mention water, the spill basically disappears.
K50:
Edit, I made a drawing that show better why most of the spill only comes from the anode itself, which ironically also eliminate most of the spill from the arc. By installing rings like the picture of the Francis light you would also remove the anode spill.