Originally posted by tuco That is an issue for me sometimes since I shoot BW. When I go out with say a either a 45mm or 75mm plus a 105mm and 165mm, I need to carry three sets of color filters. The bulk adds up. I don't do stepper rings. And I'm always looking for long exposure shots and finding a 9 or 10 stop screw-on ND filter in 82mm is difficult. That is one reason I often take my Hasselblad instead of my 67. I only need one set for all three of the equivalent lenses for it.
The filter size thing had a lot to do with which lenses I bought.
I started with the 75, 105 and 135, with the intention of adding, down the road, the 45 and 200.
This kept the filter count down to 2 of everything. At some point along the way I added a 300/4, and both 90 and 165 leaf shutter lenses.
Until the 165 leaf came along, everything is either a 67mm or an 82mm, and for the 165 I step an 82mm down to it's 77mm.
You might want to look into a stepping ring rather than 77mm filters. It saved me a pile of money.