Anyone familiar with basic camera settings like shutter speed, ISO, and aperture (f/ratio) is more than capable of capturing decent astrophotos like constellations, meteors, planetary and lunar alignments, Iridium flares, ISS flybys, star trails, and even the Milky Way. In most cases, only a DSLR-on-a-tripod setup is required. In some instances, however, an additional accessory called a cable release becomes a necessity, and without it, it is simply impossible to take advantage of the most useful feature of a DSLR camera: the bulb setting. This article explains why such an accessory is important and how you can build one (for Canon DSLRs) that performs technically the same function, equally as reliable, but costs just a fraction of the commercially available counterpart (and the best part is, you actually built it yourself!).

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