Variable ND with Hard Stops

[Brian Hirschfeld]

Hello, do you guys know if anyone makes a variable ND where there are hard stops between the different strengths of ND? Would be useful for a number of different things, But I am considering a Konica Hexar AF, and with a max shutter speed of 1/250 this would be really helpful.

[PhotoEcosse]

I don't think it would be possible.

Variable ND filters are essentially two polarising filters that are contra-rotated to cut out varying amounts of light. But the effect is not simply determined by the degree of rotation but, also, by factors such as the angle of incidence, position of the light source, etc., etc.

[Brian Hirschfeld]

I don't see what that means that it is impossible for someone to make a variable ND with hard stops...Hard stops, or really any type of click between levels of ND would be in the mechanics of the design of the filter housing no?

[Telecaster]

You could make a variable ND filter with click stops, I guess, but as PhotoEcosse notes the clicks couldn't be calibrated to correspond to t stops under all conditions. This would kinda defeat the point, no?

-Dave-

[PhotoEcosse]

You could make a variable ND filter with click stops, I guess, but as PhotoEcosse notes the clicks couldn't be calibrated to correspond to t stops under all conditions. This would kinda defeat the point, no?

-Dave-

Yep - that's what I meant, Dave. The amount of rotation required to cut light by n stops would vary according to light direction, etc.