> In a message dated 98-06-10 13:18:01 EDT, stwang@CLEMSON.EDU writes:
> 
> << What kind of light are you using for gum? My gum/ammonium dichromate
>  exposures run between 1-1/2 to 3 minutes in the NUARC, and that's fast
>  enough!
>   >>
> 
> I just use banks of BL light, and it takes me 4-10 minutes with pot.
> dichromate.
I've been using a 275 W GE sunlamp about 24 inches above the print frame. 
Exposures have been about 15 minutes.  Sensitizer is 13% (saturated ?)
potassium dichromate solution.
Judy's Post Factory newsletter was what prompted me to try gum so I'm
still looking for the "typical"  exposure to use. 
- Wayde
  (wallen@boulder.nist.gov)