I have been using "Big V" brand vellum for some years now through an HP 5100....I also started in the darkroom waaayyyyy back, & it definitely spoiled me as far as registration and dmax...for most of what we do here, vellum works well enough....But for anything with really close tolerances, it is not the optimum way to go...Density here really sux like an electrolux...really only becomes a big factor towards the lower mesh count/higher exposure time screens though...With that having been said, we have done 4cp jobs here that usually come out WAY better than one might expect off a manual press...run all the seps down the dryer belt at the same time, on file folders or cardboard, (so they don't pick up a "waffle" pattern from the belt) spray em with toner aid (Does Aqua net actually WORK?) And burn them all within the same hour to mitigate any temp/humidity changes...Whenever possible, I usually try to build in some chokes or spreads as necessary so that the press op isn't tearing her hair out trying to keep things in registration...Lotta folks have gone the vellum route since darkrooms fell out of favor..."The darkroom is dead, long live the darkroom" ! I could do 12 color hand cut negative mask separations, and EVERY color was reversed out of EVERYTHING else...Ahh those halcyon days of yore...I miss the smell of developer in the morning! LOL!
