THANKS for the answers.
OK, so, the photofloods you mention on your site are halogen or are at least equivelent temperature.
I had fun last week experimenting with macro photography using strobes for lighting. I was using the halogen so I could see to focus, and that's when I thought about using them as a light source. I'll have to look if I have those filters. Maybe for my 28mm.
This is my home made ring light for macro (photogrtaphed with a 70mm lense to show how the light works; note the "shamus penny"
)