I had a few individual filters with me occasionally. But it was often too expensive for me to fiddle with it in nature. Screwing the filter together to obtain further adding gradations is also fiddly. There are enough individual ND filters, but each time you had to change the filter again...

With this filter here, you basically trick the entire handling process. I hadn't even found out that there was such a thing. That's why I've included a small video so that you can see the function. Even though “only” ND2-32 is available here, you can still see what these products can do.
Especially for experimenting, a matter of seconds, sometimes using a different filter setting. With low filter strengths, the automatic camera is also sufficient and you can see the current shutter speed when adjusting the filter. In this way, soft water structures can be created with relatively bright light or soft clouds in the sky, etc.pp. I didn't really notice stray lights or reflections, but I'm reworking something like that on a PC anyway.

The price of this product is high, but considering that it covers several filters at once, it's not too bad. However, the general question is what kind of filters do you really need. I've had an ND8 and an ND1000 so far. Sometimes an ND 4000 would have been required (to safely create “deserted” objects/spaces).

However, I find the concept here really innovative and practical.