It would not be possible without using external filters - you can just see the top of the square filter in the iPhone photo. On very sunny days (as above) I use a Lee Filters Super Stopper which is ND15, so a 1/500th exposure becomes 1 minute. On less sunny days I use the Big Stopper which is ND10, so 1/15th becomes 1 minute.
I think for the shot above I was F8 or F11 for depth of field, but when setting up a shot it always involves a little bit of checking with apps, to compensate for ND filters and for film reciprocity, which varies depending on the film stock (eg the above shot with ND15 required a 2 minute exposure, but with Kodak Tmax100 that requires a 4â29" exposure once reciprocity is taken into account. 4+ minutes gets to the sweet spot for sea shots imho⌠For monochrome long exposures I use Tmax100 or FujiAcros100 due to predictable and manageable reciprocity. On this trip I also shot some colour long exposures using Kodak Ektar 100, cant wait to see how they come out)
Two apps that are essential for me shooting long exposures:
Lee Filters ND exposure app (free)
Film Reciprocity Timer (US$1.99)
To use the Lee Filters Seven Five system, I bought one of their adaptors for each xpan lens, and I can then load two filters into the filter holder (I have a few grads, ND3, ND10, ND15, and red, yellow filters) and the holder clips easily & securely on to the lens. Lee just released a new 85 system, which supersedes mine⌠You can buy screw on ND filters, but for ND10 and ND15 they are so dark you cannot see through them, so screw in makes framing & shooting a PITA as you need to focus & frame the shot, then add the filter etc⌠Clip on = much faster!
This is the new 85 system⌠I have had the 100mm system for much longer as use it with my DSLR. They also make a 150mm system for medium format cameras.
Apart from camera, lens & tripod, learning to use filters has been the best investment I have made for my photography. A great landscape photographer described the use of filters as âbalancing the lightâ especially when using grads (which is more tricky but not impossible with a rangefinder camera like the xpan)