amateur ceiling bounce measuremnts of my lights: Tk-20, HDS EDC, modded Predator, VPT

I just did some ceiling bounce measurements with my DX lux meter. My ceiling is white and has a rough texture to it. The lights all stood in the same pace on the floor and the lux meter's sensor was about 1 foot away from the lights. The lights were either tail standing or pressed onto the ground if tailstanding was impossible. All lights were in their brightest mode (unless noted otherwise) and were measured 1-2s after turn on. Except fo the VPT the measured values didn't change too much during the first minute. I thin the readings for the throwier lights are a little bit too high, but I can't check this accurately. Also note that my VPT V2 is the 4000K de-domed version and it has an aftermarket UCLp lens with 97% transmittance which is probably 5-10% better than the stock mineral glass lens.
Here are my readings:


The calculated lumens were based on the HDS edc burst mode measurement since this does exactly 100 otf lumens. After 4 minutes the VPT was too hot to hold :laughing:. If you have any suggestions or questions just say so .

too hot to hold? :laughing:

what effect does the nichia 219 have on the beam of the predator? is the beam smoother? does it still throw as well?

skyfire said:

too hot to hold? :laughing:

what effect does the nichia 219 have on the beam of the predator? is the beam smoother? does it still throw as well?

Click to expand...

Yes it gets that hot, but you have to remember I wasn't holding it, it was standing on the floor so it gets hot faster. 1 minute longer and I would have burned myself :laughing:.

Look at the current mesaurement I did. I just tried to measure the voltage, which is extremely difficult because the led makes you blind and you have to touch the wires/led with the dmm probes and read the display at the same time. Suprisingly I only got around 3.4V. That means the led is getting around 52.7W. I think this number is too high though because my the thick wires I used for measureing the current probably have less resistance than the tailcap of the light. But now you know why it gets sooo hot.

The Nichia 219 doesn't really change the beamprofile at all (on a white wall the beam is still a bit ugly as before, it's not smooth like some other lights). The biggest difference is that it doesn't blind you as much anymore when you shine at a wal from close distance. Color rendering is obvioulsly much better.