First of all: this filter is really, REALLY dark. It's a little on the dark side even for direct shots of the Sun. I suppose it would be useful for close-ups of welding arcs, or maybe detailed photos of a nuclear detonation. Or EXTREMELY long exposures in bright daylight (sandy beach, high noon, f/11, ISO 100, 20 minutes?)

This filter was well-packaged, although the ribbed side of the case did leave a small "print" on the filter's front surface. I haven't yet tried to remove it.

The attached solar image was shot on a Canon 6D II, 100-400L at 400mm, 1/160, f/8, handheld and manually focused, stabilization on. I had to crank the ISO to 2500 to get this level of exposure. No other manipulation besides cropping and exporting as JPEG.

Ideally, for direct solar photography, I'd prefer a filter three or four steps LIGHTER than this, shooting at lower ISO -- but I'm still going to have plenty of fun with this one!

There's no specific information about IR or UV blocking on this filter, so I'm a bit reluctant to use it with the optical viewfinder. It's PROBABLY safe, but I err on the side of caution when it comes to my eyes. I didn't see any signs of trouble with my camera during the five or ten minutes that I was taking test shots.

Recommended, but know what you're getting into. And don't be afraid of the dark!