Have you ever seen photos of retro movie sets where the cameras seem to be bedazzled with lenses? Of course you can only film via one lens at a time, but mounting multiple lenses on a turret as was done in those days has certain advantages –particularly when working with tiny M12 lenses, like our own [Jenny List] recently did with this three-lens, Pi-zero based camera.
Given that it’s [Jenny], the hardware is truly open source, with not just the Python code to drive the Pi but the OpenSCAD code used to generate the STLs for the turret and the camera body all available via GitHub under a generous CC-BY-SA-4.0 license. Even using a cheap sensor and lenses from AliExpress, [Jenny] gets good results, as you can see from the demo video embedded below. (Jump to 1:20 if you just want to see images from the camera.)
The lenses are mounted to a 3D printed ring with detents to lock each quickly in place, held in place by a self-tapping screw, proving we at Hackaday practice what we preach. (Or that [Jenny] does, at least when it comes to fasteners.) Swapping lenses becomes a moment’s twist, as opposed to fiddling with tiny lenses hoping you don’t drop one. We imagine the same convenience is what drove turret cameras to be used in the movie industry, once upon a time.
Neat, a perfect opportunity to discuss parfocal adjustment and back focus.
Turrets were once found even on some consumer movie cameras but were quickly obsoleted once zoom lenses were available.
The idea came back with phone lenses, except that the turret is replace by multiple sensors.
The latest Huawei phone has two tele lenses that share the same sensor, but nothing rotates on the outside though.
I always thought it was a bit of a waste to have 3 or 4 sensors in a phone when the difference is just the focal length and I wonder if this will become a thing now.