People keep asking us if these pictures are made by us. They are. Really. This is the equipment we use.

Equipment

Tripod. First of all, we have ~50kg of equipment that needs to be positioned with the accuracy of 1-2 microns. That is the hundredth of a human hair… So we need to put all of it on a sturdy tripod. On the top of the tripod there is a so called equatorial mount. This is a saddle that can be rotated on two axes. It does two kinds of movement. It can position the telescope to whatever object you want to take a picture of. It can also counteract the Earth’s rotation to track the stars as they move along. This mechanical problem can’t be solved purely with motors and accurate gears. So a small guide camera detects the tiniest deviation and feeds back this information to the motors to correct.

Telescope. We have an apochromatical telescope. That is a telescope with a lens. It is about a meter long and 10kg. The goal is to make faint things brighter, not to magnify things. There is a strap around the lens that heats it up a bit, just above the dew point, so it does not get foggy. There is a focuser on it. On our setup this is adjusted by a small motor. An integral part of the telescope is the field flattener. This is a few additional lenses that correct certain optical aberrations, similarly to glasses that humans may need.

Camera. The main camera we use is made specifically for scientific applications. You can’t look trough it, it does not have a screen and it is monochrome. It has to be cooled, to around -20C. Since this is a black & white camera, we put filters in front of it. For example, we have red, green and blue filters. To end up with a color photograph we cycle trough these filters and combine the results. To make this easier these filters are stored in a filter wheel and it can be turned electronically.

Electronics. All of these motors, cameras, heaters and coolers need power. The adapter is quite big. There is also a small power distribution unit sitting on the top of the telescope tube that connects everything together. It provides the correct voltages, measures energy consumption and allows the different devices to be turned on and off from a computer. It also measures the temperature and humidity. This information is needed to know how much heating is required for the lens and how much cooling is possible for the camera. The computer that controls all of the gadgets is a Rasperry PI, that is also riding on the top of the telescope. We connect to this computer remotely from a desktop computer or a mobile device.

We have been building our setup for 20 years, so naturally it is super optimized. But you can take astrophotos with a lot less. This is a picture taken with just a mobile phone: