The How Zone

Photographing the Sun

Telescope Setup

If you haven't read the safety precautions, please do so now. Also, while you are setting things up, be sure to leave the cap on both ends of the telescope.

Our telescope is a refractor and has a 90° star diagonal. I remove this piece and connect the largest (lowest magnification) lens to the telescope for a straight path of sunlight. I don't have experience with other styles of telescopes, experiment and see what works best. To make it easier to locate and align the Sun's image with your projection surface start with the lowest magnification. Once everything is setup and working you'll have plenty of time to experiment with other lenses.

Projection Setup

The white surface on the right is a large sheet of foam backed paper board. Picks some up at a hobby shop for around two bucks, it works great. I've also taped sheets of printer paper to a sheet of cardboard and even used a bed sheet, both with limited success and quality. Depending on the size of your telescope and the lens, you will need to place this surface three feet away or further. The goal here is not to have a pinprick of sun, but to get a large projection that shows off the sun spots.

Before you pop off the lens caps keep repeating to yourself: I will not look into the telescope to align it with the sun! It's easy to get carried away with the moment.

Loosen the telescope set screws a bit so you can move the "fat" end of the scope towards the sun while keeping a look at the foam board. Use a slow zig-zag: back and forth and up and down to track down the sun. Or, you could use a constantly expanding circular pattern, like my dog uses to find a lost tennis ball. At first it most likely won't be in focus, but you'll know it's the sun all the same.

Clouds and Sun on sheet

If it's a cloudy day you might see something like this, where a cloud is moving in front of the sun. This is using a white sheet (can you spot the dog hairs?) draped over the porch railing. Works in a pinch but it distorts the sun a bit.

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