Filters can also help you achieve long exposures and greater tonal contrast.
black and white in lightroomPersonally, I love long exposures that capture a sense of movement in a scene. This concept works really well in black and white photography too, especially for landscapes when water and clouds are key parts of the scene. With a longer exposure, the whites in the moving water (which become the highlights in your black and white image) are spread over a wider area, helping increase tonal contrast and texture differences. The texture is particularly increased if there are crisp, stationary objects in the photo which juxtapose the soft movement blur. You can read our whole tutorial on how to take long exposures. Filters can also help you achieve long exposures and greater tonal contrast. An ND filter passes less light into the camera so the shutter speed has to compensate by getting longer, in turn achieving more movement blur. A polarising filter can also help greatly by darkening a blue sky and making clouds pop, which when converted to black and white can often add a striking mood to a photo. See here for a whole tutorial on understanding and using filters.