Grumpy_Mike:
But, and I stress this, it seems to be working.
Yes it might appear to be working.
smiley-lol Good enough for amateur work?
Well that depends on how long you want it to continue to work, and how much light reduction you can stand and how wide a temperature range you want to work in it.
How much light reduction do you think it is experiencing? It's already so bright I can't directly look at it, at least inside. I wonder what it looks like outside.
Edit: I think I know what you mean, degradation over time.
I think I like Chagrin's idea with the PT4115. When I receive those, I am going to rebuild this using the PT4115 part and see how well it works for me.