B+W 110 ND filter

Concept: 3 out of 5
Execution: 2 out of 5
Yeah, but: Ten stops is a lot of light.

The Long Version: The 110ND is a ten-stop neutral density filter, which means it lets in only 0.1% of the light that hits it. That's dark. Really, really dark. In fact, it's so dark that it's not really neutral any more. Images taken with it have a reddish hue that doesn't quite go away, even with some custom white balance trickery.

Having a ten-stop cut filter means doing things like a fifteen-second exposure in full sun at noon at a mere f/16. For extra fun, adding a polarizer will cut another stop-and-a-bit, which more than doubles the exposure time again. To play with this kind of time takes a very solid tripod and probably some sort of way to lock the shutter for "bulb" exposure. Even then, I feel like a lot of my images aren't as sharp as they should be. It's impossible to tell if that's from the filter directly, or from the effects of city vibration transmitted up the tripod. Given B+W's reputation, I'll give them the benefit of the doubt, but it doesn't seem possible to abuse light this much and not have some consequences.

I've seen some really good photos taken using this extreme ND filter, but none of them have come from my camera. I've taken a few smooth-water shots in my time, and while this filter's great at them, they've never really excited me. Generally I'd say that this filter falls into the same category as a Lensbaby: an expensive novelty item that makes photography into a difficult low-fi exercise, but with a genuine-if-narrow band of real value that some people will benefit from. Like the lensbaby, the effect can be approximated in post-production, in this case by stacking multiple short exposures, but the effect never really rises above being a mimicry and misses the chance for the unexpected to happen. I'm glad to have this filter, and occasionally bring it out to play, but if it broke I wouldn't buy another one.