Paul C. Buff, Inc. Technical Forum

Luap,

I want to personally thank you for your help with this project.

Dave

You are very welcome. I always try to support science and intelligent work like this. When I started back in 1980 I asked Speedotron for help on a very similar project and got the cold shoulder. So I became a competitor.

And kicked them to the curb. Revenge can be sweet, although I'm guessing there were other motivators.

I will be trying to get to an event in Mount Vernon, Ill. on the weekend of Sept 17/18. I could probably swing by Nashville on Monday morning the 19th and thank you in person. I can bring the projector for you to look over too.

MaloDave

You'll have to let me know in advance. I work at home and are rarely at the office.

Any problem with the flashtube heating the LEDs? If you shoot heavily at high power the heat might exceed the LED capabilities.

We don't shoot that fast with the projector, so it doesn't seem to be a problem. I have a piece of mirror polished stainless coming that I can put a few holes in so that the fan on the power supply can blow across the LEDs/Flashtube.

Dave

Just a general concern about LEDs in high power flash units. I believe LEDs, and most solid state devices, are generally limited to 150°C maximum junction temperature. The junction itself can generate the better portion of this from its own power dissipation. It's quite possible the flashtube could heat the ambient in close proximity to well over 200°C.

If you fire a 600WS tube a few times in rapid succession in the dark, you will see the envelope actually glow red for a few seconds after it shuts off.