In a previous post, we touched on variable neutral density and how it's not really viable for an ultra wide-angle lens.
Retaining Shallow Depth of Field
When creating an image or video, there are many factors at play at all times. Exposure is a huge part of that, and controls whether or not the scene is at the correct brightness. The two extremes of a scene's dynamic range, highlights and shadows, are most prone to clipping, as a severely underexposed image loses detail in the shadows, while a severely overexposed image loses details in the highlights. While there are many factors of exposure, the key one that's relevant to depth of field is aperture.
Another thing to consider is depth of field. Depth of field dictates just how much of the scene is in focus. Two same scene with completely different depths of field could potentially read as a completely different scene.
While not directly affected by exposure as a whole, depth of field is dictated by the lens aperture. The smaller the aperture number (or the wider the physical aperture), the shallower the depth of field. But a wider aperture also lets more let in, so you would usually have to compensate with a shutter speed. If you were to follow the Sunny 16 rule on a bright, sunny day, your settings would be (or fairly close to) f/16, 1/100 second, ISO100. In terms of depth of field, f/16 has a fairly large depth of field, so there's certainly less foreground-background separation. If you wanted to shoot a f/2.8, for example, your shutter speed would have to be 1/3200nd of a second. For stills, that'd be perfectly acceptable, but for video, where your shutterspeed is dictated by your framerate, footage shot at 1/3200 second wouldn't be particularly useful.
With our ND Throttle, you're able to keep your shutterspeeds where you want them without compromising your choices in depth of field. In one of our older videos, we highlight this on the fourth point.
While neutral density can help you control your aperture and depth of field issues that video can present, it can also helpful when doing long-exposure photography. Long-Exposure Photography, as the name suggests, is just any sort of photography that uses a relatively long exposure time to show a subject in a way we cannot with our own eyes. Often times with long-exposure photography, you will see longer shutter speeds of fifteen seconds, thirty seconds, or even exposures lasting hours.
Long-exposure photography is popular with people who like waterscapes, seascapes, or just nature shots that give water a smooth, dreamy look, as in the examples below:
1/60 f/5 ISO200
5" f/5 ISO200
Another creative use of neutral density can be seen in this video, where the photographer takes pictures with neutral density to incorporate motion blur into the scene he's photographing. After compiling multiple photos into a time-lapse, he got a smoother look to his time-lapse.
Obviously, you aren't limited to waterscapes and city scenes if you're interested in long-exposure photography. These are just some examples. Whatever you decide to shoot, make sure you've got a tripod, or some steady hands!
When we originally launched the ND Throttle line in 2014, the biggest drawback was that our Canon EOS versions lost aperture functionality when put onto an adapter with out electronic contacts, since Canon EOS lenses need power to control their aperture. Six years later, and we've combined the best parts about our Fusion Smart AF adapters with our built-in variable neutral density filters from the ND Throttle line to bring you our Fusion ND Throttle adapters. The Fusion ND Throttle adapters have electronic contacts to let you control aperture, focus, and Image Stabilization on compatible Canon EOS lenses and select third-party Canon EOS-mount lenses.
Outside of aperture, shutter speed, and ISO, neutral density is another way to control exposure. The ND Throttle family of adapters makes this much easier to do with the built-in dial on our adapters, so you can use as much (or as little) neutral density as you want, to suit your circumstances best.