What is recommended for (tethered shooting) using Nikon and Canon Cameras. Should be able to zoom, focus and shoot from input device, mouse/keyboard or preferred touch-pad on laptop. Connection via USB a must. Does not have to include editing software.
I'd recommend an EyeFi SD card. Amazing little things for sending photos to the computer but they won't give you nice tethered modes (eg remote control) over the camera so might not fit your requirements. If you're just looking to send your photos to your computer in real time, check it out.
Otherwise take a look at gphoto2 (installable from the repos). Either check the website or install it, plug your camera in and run
From there you can do different things. Mine is a proper DSLR so there's no zoom control for me but I can take photos and script various things to happen like taking silly-wide exposure triplets for super-high dynamic range photos and do interval shooting for time-lapse imaging.
It really is a very vast application. You'll need to poke around in the docs for a while before you've mastered it (I certainly haven't yet!)
Oh and I recommend an external power supply for the camera if you're doing time-lapse. The USB connection really drains the battery fast.
Something to get you started assuming gphoto2 can find the camera (in the
That should capture a photo and save it in the current directory.