Originally Posted by jnanian
So I think my original guess regarding the general look you were after was on the right track. I'd then say a tricolor blue (wratten 47 or 47B) would simulate the effect well as it "cuts" pretty much everything but blue. You'll get those characteristic bleak-white skies, accentuated atmospheric haze and open shadows under daylight. The 47B is darker than the 47 but might be overkill and not add much other than lengthening exposure time.
On the other hand if you are also currently using VC paper for negatives, sensitivity is to blue and green so I guess you'd need more of a blue-green filter (wratten 44A is the only one I can think of). There is also a 44 which is similar to the 44A in the visible spectrum but is designed to also absorb UV light, so that's obviously no good if you're doing UV exposures.