Noelle

I would add to everyone else's good advice that you should bracket your
exposures around a value below what you use for bright field.  I use a
Nikon set up and Fuji Color 400 and bracket around two or three steps
below bright field exposure setting.  The center value depends on how
bright the background is and your selection of that value is a shot in the
dark as it were.  But the illumination grows with experience.

Yours for a good green glow

John Carroll Dennis
Anatomy, Physiology, and Pharmacology
109 Greene Hall
Auburn University, AL  36849