You'd think the overlap between landscape equipment and studio equipment would be pretty straightforward. Camera, yes. Lens, yes. Tripod, maybe. Filters? ... what?
Below are some interesting uses I've found for landscape filters, and I mean the ones designed specifically for landscapes - not your red/yellow/uv kit.
Here's my friend Constantin showing off an uncanny ability to keep his body still whilst shaking his head. As before the stationary elements of the scene stay sharp accentuating the movement of the subject's head.
10-stop neutral density filters are used by landscape photographers who want to exaggerate movement. This image I took up in Wast water was exposed for 20 seconds, allowing you to see both the motion blur made by the clouds and the calmed nature of the water in the foreground.
By permitting only a thousandth of the light to hit the sensor you're going to require a fast aperture or a high ISO to use these indoors, or you can place the camera on a tripod and hope the subject stays still enough for 2/3 seconds. The third option is to use incredibly powerful strobes to freeze motion, but that would rather defeat the option of the filter in the first place.
Here's an image taken with a 0.6 ND soft Grad, a filter designed to decrease exposure in one half of the frame without obstructing the other half. To allow the subtle in reflections in the foreground to show up without overexposing the colour in the sky required the darker area to cover the sky, and you can see that the whole image looks evenly-exposed, despite the sky being significantly brighter.
This image was taken with a ND filter placed horizontally, allowing the gradual drop-off into shadows on the right side of the frame. 'Soft' graduated ND filters start to fade into darkness at the centre of the filter but there is no 'Hard' division, the darkness is added gradually. This gives the above picture it's moody 'stage lit' feel, whilst allowing us to see the blue gel light filling the shadow he casts on the backdrop behind him.
I've yet to see a circular polariser used on a shoot but I've heard that it's possible to place sheet polarisers over the front of strobes and have strobe reflections negate themselves when a circular polariser is places on the lens. Maybe this could provide finer detail in areas of more reflective skin but that's something I'm yet to try.
If you have any more ideas please let me know!