First of all you turn your easel 90 degrees so it can accept 4x5 film instead of 5x4 (which I've never
seen - perhaps it has something to do with which side of the Greenwich Meridian you're on) - but
seriously ... To do high-quality work you need an actual vacuum filmholder on the baseboard and a
lens suitable for duplicating. I use Apo-Nikkors rather than general enlarging lenses for this purpose.
Everything must be exceptionally precise, and your light source should be quite even. Choice of film
can be any number of things, but if you choose ortho it not a lot different than shooting ortho outside, except that it will be slower under a tungsten light source and be slightly skewed unless you
balance your colorhead to a cooler Kelvin temp resembling daylight. Takes a little practice, but in principle this is pretty simple conceptually.