A DIY digital telescope build using 5-inch PVC pipe, a 114 mm concave mirror, and a Raspberry Pi Zero 2W has given maker [Makestreme] the clear view of the night sky that off-the-shelf budget scopes simply could not deliver. Rather than settle for a cheap 50 mm aperture model, the decision was made to build something considerably more capable from scratch.
Mirrors, PVC and 3D Printed Mounts
The optical heart of the build is a 114 mm diameter concave reflector mirror sourced from Amazon, mounted inside a length of 5-inch PVC pipe cut to just under a metre. That length was chosen to match the mirror’s 900 mm focal length, keeping the geometry honest and the optics properly aligned. 3D printed components handle the mirror mounting and allow fine adjustment for focus and collimation, which is exactly the kind of fiddly alignment work that traditionally requires either expensive hardware or a lot of patience with a commercial scope.
Collimation on a Newtonian-style reflector matters enormously. Get it wrong and even a fine primary mirror will produce a blurry, astigmatic image. The printed parts here give [Makestreme] repeatable control over that alignment without relying on the tolerances of mass-produced metal rings.
A Smart Telescope for the DIY Digital Telescope Build
Where this project diverges from a traditional reflector is at the focal point. Rather than fitting an eyepiece drawtube for direct viewing, [Makestreme] mounted a Raspberry Pi Camera Module 3 there instead, turning the whole instrument into a smart, camera-first telescope. The camera feeds into a Raspberry Pi Zero 2W, which runs a Python script hosting a small web server. That server streams the live camera feed and exposes controls for brightness, exposure, and gain, all accessible over a local network connection from a phone or laptop.
Power comes from a single 18650 lithium-ion cell fed through a 5 V boost module, keeping the whole rig portable and free from mains cables. In practical terms, that means the scope can be taken out to a dark field away from streetlighting without needing an extension lead, which makes a real difference to planetary and deep-sky work alike.
Aiming is handled with the help of apps including SkyMap and SkEye, which overlay the current sky on a phone screen and help point the tube at whatever object is on the evening’s list. It is a sensible pairing: the telescope provides the light-gathering and imaging, while the phone handles the star-chart duties that would otherwise require either a motorised equatorial mount or a working knowledge of star-hopping.
Why a Camera-Based Build Makes Sense
There is a strong argument for going camera-first rather than eyepiece-first on a homebrew reflector. An eyepiece demands a precisely machined focuser drawtube, careful spacing from the secondary mirror, and a secondary mirror itself, adding components and alignment steps. A camera sitting directly at the focal point of a primary-only design simplifies the optical train considerably. The image is viewed on a screen rather than directly, which also makes sharing the view with others far easier, particularly useful when trying to show a specific feature on Jupiter or a faint galaxy to someone who has never looked through a telescope before.
Amazon supplied the primary mirror here, which points to how accessible the raw components for reflector builds have become. Combined with 3D printing for the structural parts and a Python-based software stack for the imaging interface, the barrier to building a genuinely capable backyard instrument has dropped considerably. The 114 mm aperture comfortably outperforms the 50 mm that prompted the whole project in the first place, and the smart interface means the images can be saved, shared, and stacked for even better results.
