If you can find both a 40.5mm circular polarizing filter and a 40.5mm linear polarizing filter - you can stack them to create your own 40.5mm variable density ND filter. They're not pretty but they work.
Great tip. My new V1 + 10mm + FT-1 arrived today, & am looking forward to putting it through its paces when the memory card arrives. I will try a pair of 52 mm polarising filters and an HN-1 lens hood from my AI lenses, plus the 40.5 to 52mm step up ring I have ordered. The 52mm filters and lens hoods look like a perfect match for the 10mm f2.8 being the same outside diameter as its silver ring, and probably the 1 series zooms as well, and i think are a chunk cheaper than the larger filters needed for most more recent Nikkors. Giles
Fri 27-Jul-12 04:31 PM | edited Fri 27-Jul-12 04:34 PM by Bob Simrak
My own set-up for the V1 uses a 40.5mm to 52mm step-up ring and a circular and linear polarizing filter.
The order is important. The circular polarizer should be closest to the lens then the linear polarizer. With this combination on the 10-30mm lens I have an exposure range from 1/250 @ f/4.0 ISO 100 to 1/30 @ f/4.0 ISO 100 in bright sun.