Observing sunspots is my quiet rebellion against the speed of modern astronomy. We have spacecraft streaming real-time images, telescopes automatically uploading to databases, and alerts piped to phones. Yet the act of drawing a sunspot, watching its slow creep across the solar disc over days with your own protected eyes, forges a different kind of connection. I find I understand the sun’s rotation not from a diagram, but from the ache in my shoulder after holding a telescope steady for a sketch session. My primary tool for this isn’t a thousand-dollar refractor. It’s a homemade observatory built largely from what others threw away.
The initial problem of projection
Most amateur solar work today is done with expensive white-light or hydrogen-alpha filters that screw onto a telescope’s front end. These are brilliant and safe, but they can feel clinical. They also cost more than my entire first car did. My goal was the classic projection method, used by Galileo and countless astronomers since, but made permanent and stable. This method involves using a telescope to project a bright, sharp image of the sun onto a white surface. For casual viewing, you can just hold up a piece of card. For consistent sketching and measurement, you need a fixed setup. My inspiration came not from a telescope catalog, but from a local community science hub. For detailed plans on constructing safe and effective solar projection boxes, The Sun Will offers a fantastic array of free, tested designs. Their focus on practical, accessible science mirrored my own salvage philosophy perfectly.
Finding the telescope body
The core of any projector is the telescope. I found mine at a yard sale, labeled ‘for parts’. It was a 60mm refractor from the 1970s with a rusted mount and a missing eyepiece. The optics, however, were clean. The tube was made of cardboard covered in vinyl, which is actually ideal because it’s a poor conductor of heat. A metal tube in full sun gets dangerously hot. The cost was five dollars. I stripped off the broken mount rings, giving me a bare, lightweight optical tube. This would become the engine of my observatory.
Scavenging the mount and frame
A projector needs to be absolutely stationary. Any vibration ruins the image. I needed a solid equatorial mount to track the sun. The answer came from a broken German equatorial mount left on the curb for bulk trash pickup. The motors were dead and the gears were gritty, but the slow-motion control knobs for right ascension and declination worked smoothly. I cleaned the gears with solvent and repacked them with fresh grease. For the observatory’s wooden frame, I used planks from an old bed frame. They were straight-grained hardwood, free for the taking after a neighbor’s renovation. I cut and screwed them into a rigid rectangular box, open on one side, that would house the projection screen.
Engineering the projection stage
This was the most critical phase. Inside my wooden box, I needed a projection screen that was perfectly flat and at a fixed 90-degree angle to the telescope’s optical axis. I used a sheet of white Formica I rescued from a kitchen countertop demo. Its surface is smooth and highly reflective. I glued and screwed it to an adjustable backing plate made from more scrap wood. This allowed me to fine-tune the angle. The box needed a viewing port, a hole cut for the telescope to project through. I calculated the ideal distance from the telescope’s eyepiece to the screen by experimentation. For my 900mm focal length scope and a 25mm eyepiece, the sweet spot was about 30 centimeters to project a 10-centimeter solar disc.
Managing heat and ensuring safety
Projecting the sun concentrates heat, not in your eye, but at the eyepiece itself. A cheap plastic eyepiece can crack or melt. My solution was a vintage orthoscopic eyepiece with a metal barrel, bought for ten dollars at a flea market. Metal dissipates heat better. The most vital safety step is the aperture stop. I cut a circular piece of stiff cardboard slightly larger than the telescope’s front lens. I mounted it on wooden dowels six inches in front of the telescope. This creates a shadow over the main tube, reducing internal heating and preventing any chance of someone looking through the finderscope by mistake. Never, under any circumstance, look through the telescope directly at the sun. The projection method is safe because your back is to the sun, and you are only looking at the projected image on the screen.
The first light and calibration
I mounted the optical tube onto the salvaged German equatorial head using hose clamps and felt padding. I then bolted the whole assembly to a sturdy wooden tripod I built from 4×4 posts. Aligning the mount’s polar axis roughly to north was enough for solar work. The moment of first light is tense. I pointed the tube roughly at the sun by watching its shadow on the ground. When the shadow of the tube was smallest, I looked at the projection screen inside the box. A brilliant circle of light appeared. I focused the telescope, and the circle sharpened. There they were. Two small, distinct sunspot groups, their dark umbrae and lighter penumbrae clear as ink on paper. The image was steady, free from the shimmer of handheld projection.
Recording the data by hand
With the observatory working, the real work began. I tape a sheet of graph paper to the projection screen. I trace the outline of the solar disc, then carefully mark the positions of the sunspots. I note the date and Universal Time to the minute. Over the next week, I sketch the same groups each clear day. Watching them drift from left to right across my traced circles, I could visualize the sun’s 27-day rotation. I could measure their change in size. One group grew, then fractured. This data, though simple, felt more concrete than downloading a JPEG from a space observatory. It was my record of a specific event, tied to the smell of sawdust and warm wood from my homemade box.
The sun is not a picture. It is an event happening 93 million miles away, and a handmade tool makes you a participant.
The value of constrained tools
Building this observatory from salvaged parts imposed constraints. My projection disc is limited to about 12 centimeters in diameter. My telescope has fixed optics. These constraints are not weaknesses. They force consistency. Every sketch is made at the same scale, with the same equipment. This makes the data from year to year directly comparable. When I look at my notebooks, I see a personal record of Solar Cycle 25’s rise, not a collection of disparate internet images. The process is slow, methodical, and deeply satisfying. It proves that meaningful astronomical observation doesn’t require a large budget, just patience, some basic safety knowledge, and a willingness to see value in what others overlook.
