Review on Astromania 2 12Nm S Ll Filter by Mike Johnston

The thread on the filter is excellent, the filter is clean, delivery is fast! Just a note: This filter is DARK! Some reviewers say this filter doesn't work. but that's because so much of the visible spectrum is cut off that very little light gets through. That's how it should be. I tested it with an UNMODIFIED DSLR (Canon T3i) and found that it cuts the light down to THREE f-stops! This means that the exposure time is at least 8 times longer than the exposure time without a filter. So if your typical exposure was 100 seconds, then your exposure with this filter should probably be 800 seconds! That's over 13 minutes per subwoofer, again with an unmodified DSLR that still has an IR/UV cut filter mounted over the sensor. Now you know!