Great long exposure photography tip: ND filters!

You’ve probably seen those gorgeous landscape photos of smooth silky waters, blurred waterfalls, and hazy clouds. So how do you go about taking shots like those yourself? Well the answer is Long Exposure. To capture long exposure frames such as those, there are a few things you need to make sure of. Namely: a slow shutter speed (the slower the better, usually a few seconds or longer), a very narrow aperture, and a very slow ISO speed (both to be able to let the least amount of light in, resulting obviously in longer shutter speeds, which is what we’re after and also to keep image noise at a minimum since noise tends to become more obvious with longer exposures).

Now since we’re gonna be shooting for long exposure times, an indispensable piece of equipment in long exposure photography would be a strong sturdy tripod to hold the cam still during the exposure.

You might find yourself going as slow as possible (in terms of shutter speed settings), after stopping your lens aperture all the way down and choosing the slowest ISO you have, yet still not getting a slow enough exposure, like maybe if the sun is too bright. What you need in such cases is either a polarizer filter, or even much better an a neutral density filter (ND filter). If you don’t have access to either of those, you will need to wait till the sun goes down so you’d be able to get slower shutter speeds while the lighting conditions are low.

ND filters come in all sizes, shapes, and brands. They’re basically colorless (clear) or grey filters, with the ideal being able to reduce and/or modify the intensity of all wavelengths (colors) of light equally, giving no changes in hue of color rendition. Their main purpose is knocking down the amount of light passing through your lens and onto you digital sensor or photographic film, allowing for more flexibility and control over aperture/shutter/ISO settings in varying shooting conditions, like using slower shutter speeds and obtaining shallower depths of field not otherwise possible.

ND filters come in various optical densities (shades), which are most commonly measured by attenuation or f-stop reduction. The higher the attenuation of the filter, the darker it is, and the less light it is built to let in through the lens. So an ND8 filter is darker than an ND4 filter, and consequently lets less light in allwoing for longer exposure times. Likewise an ND4 filter is darker than an ND2 filter, and also lets less light in.