Mount any 1.25″ filter cell (including Star Analyser or Rainbow Optics gratings) to DSLR filter threads. This filter fits Canon 58 mm lens cap threads. If your camera's lens cap threads aren't 58 mm, you'll need to add step-up or step-down rings.
If your camera's filter threads are not 58 mm, you will need some step up or step down Adapter Rings (link).
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