SGP acquiring images from simple camera question

Does anyone know of a way to trigger exposures on a camera using a USB controlled cable release from within an application such as SGP - I would set the camera on Bulb and have a USB electronically controlled switch doing the exposures. With bulb setting, the ‘on’ duration is the exposure time.
I can always use an intervalometer but I want to dither between exposures.

APT or DSLR Shutter (does this dither?) might be a better option here. SGP is generally more focused on automation.