So far I only own 3 and 6 stop neutral density (ND) filters and have primarily used 6 stop ND filter (B+W 6 Stop ND Filter ) to create silky smooth water effect typically seen in my waterfront cityscape photos with long exposure (as seen in my Top 50 Photo Gallery). Then, I’ve recently tested out a borrowed 10 stop ND filter (B+W 10 Stop ND Filter ) for the first time, with an intention to purchase if finding it useful.
To be honest, I’ve been reluctant to try out 10 stop ND filter, as it seems much harder to handle (e.g. even 1 second of base shutter speed gets extended to whopping 17 minutes and 4 seconds). Also, I’m very satisfied with the smoothed-out water effect achieved by my favourite 6 stop ND filter, thinking that 10 stop ND filter won’t be needed.
Anyway, this is what I got. Note that the only the first photo was shot with 10 stop ND filter attached (with 343 seconds exposure). The second photo was shot with 6 stop ND filter attached (with 162 seconds exposure) immediately after the first shot.
To tell the truth, the photo on top isn’t my first attempt with 10 stop ND filter. A few days prior, I had tried a super long exposure shot (about 10 minutes) leading up to the end of dusk at this same location, expecting to capture the most epic blue hour cityscapes ever! Sadly, the attempt turned out to be a complete failure, as digital noise caused by long exposure was too unbearable (especially affecting buildings badly).
So, I came back again and re-tried by using much shorter shutter speed (still 343 seconds at f/10, though), which means that the exposure had to be started earlier (3 minutes after sunset, 19 minutes before dusk). Still having almost 20 minutes left until the end of dusk, not many city lights were lit up, and it was inevitable for reflections on the water to be very subtle. There might be people who prefer the first photo, but I’m sure the majority (me included) will pick the second one, perfectly timed blue hour photo (shot 7 minutes before dusk).
Good in Daylight, but Not for Blue Hour
I guess 10 stop ND filter can still be put to an effective use at pre-dusk, golden hour or even in daylight (as it’s hard to get long enough exposure with lesser strength ND filters when the sky is bright), but not quite at blue hour.
After all, I’ve decided not to purchase 10 stop ND filter. I understand that it’ll open doors for more creative options, but as far as my interest of “cityscape photography at blue hour” is concerned, it doesn’t seem to add as much value as 6 and 3 stop ND filters do.