@brokenkeys said:

I think he's refereing to this one (about halfway down the page):
http://www.sketchupartists.org/presentations/techniques/

yep, that's the guy; can you direct me to where this might have been discussed? thx

ufff, sorry
SU for architectural visualization Beginner's guide written by Robin de Jongh
pg221 Richard Jeffery sketchy pencil technique

the richad jeffery technique as described in deJongh's biginner's guide

i'm having problems with this NPR technique in particular with pencil shading in GIMP.
can anyone direct me to the forum where this technique is discussed. thanks
p.stupendo