Having stumbled upon @patdavid 's tutorial on Faking an ND Filter for Long Exposure Photography, https://patdavid.net/2013/09/faking-nd-filter-for-long-exposure/, I thought I may as well give it a try!
Setting camera on tripod in front of a waterfall at a local park, the slowest shutter speed I could get was 1 second at f/8 @ ISO 100.
So I shot 15 images in quick succession, then “averaged” them together using imagemagick.
Here is one of the 15 frames:
And the result of averaging together the 15 frames using imagemagick as per @patdavid 's tutorial:
Now this isn’t the worlds most spectacular photograph, as I was just really shooting some photos to try this technique out. It was 15 .jpg files I blended together for this image. Thankfully my new Canon 750D, compared to my old Pentax K100D can certainly rattle off continuous shots without a hiccup!
While this method does require a bit more work to get a single “long exposure” it is certainly cheaper (apart from storage space) compared to a B&W 10 stop ND filter!
Certainly something I’m going to experiment with.