Photographing the night sky can be done with a camera on a tripod.

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What do you need:

- A camera

- A lens

- A tripod

- A remote

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The camera

The most common cameras used are: DSLR cameras. You can easily set this on different levels (aperture, focal length, etc.).

You can also connect different lenses to it, allowing you to take different types of photos.

- Pictures of the Milky Way

- Pictures of galaxies

- Pictures of nebulae

- Time lapse

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The tripod

Not only the camera is important, but of course also the tripod.
You can of course use any tripod, but an important requirement for the tripod is that it is sturdy/stable. Because so many different lenses can be connected to a DSLR, it must be taken into account that the tripod is stable even with your heaviest lens. 
In addition, a stable tripod is also important against vibrations. Every step you take can cause a vibration that can result in blurry photos.

So before you start taking photos, make sure you stand some distance from your camera or sit quietly. A timer on the camera is often used before taking photos or a remote control.

 

Which lens for what kind of photos

Lenses come in many sizes.

It is important that a lens catches as much light as it can. They do this if they have the smallest possible aperture (f). The smaller the aperture (f) of the lens, the more light they collect.

A frequently used lens for wide-field recordings is a 50mm lens. These are available in different aperture sizes f1.8, f1.4 and f1.2. The smaller the mm of a lens, the larger the image.

 

If you want to focus more on deep sky objects, you will need a larger lens, for example, a 300mm lens.
 

The remote control

A remote control for astrophotography is almost a must. The advantage of this is that you can operate the camera without touching it. This means there are no vibrations, which reduces the chance of a "bad" photo.
Some remote controls also allow you to set the number of photos and time per photo. This goes further than what you can set in the settings on the camera.

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Now finally the photography

An important part of astrophotography is the exposure of the photo. To calculate how long you can expose with a lens without getting star trails, as a result of the rotation of the Earth, you can apply the following formula.

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Divide the number 500 by the focal length multiplied by the crop factor of your camera.

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Here is a list of the three most commonly used crop factors for SLR and system cameras:
Canon non-full frame DSLR cameras have a crop factor of: x1.6
Nikon non-full frame DSLR cameras have a crop factor of: x1.5 (the Nikon 1 system cameras have x2.7)
Sony non-full frame DSLR cameras have a crop factor of: x1.5

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• 14mm on full frame: (500/(14 × 1) = 35 seconds exposure

• 50mm on full frame: 500/(50 × 1) = 10 second exposure

• 300mm on full frame: 500/(300 × 1) = 1.6 seconds exposure

• 14mm at 1.6 crop: 500/(14 × 1.6) = 22 seconds exposure

• 300mm at 1.5 crop: 500/(300 × 1.5) = 1.1 second exposure

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The 300 rule is often used instead of the 500 rule because star trails are formed more quickly with a larger focal point. You have to experiment with this yourself.

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If you want to calculate the focal length of your lens on your camera, multiply the mm of the lens times the crop of the camera. For example, a 300mm lens on a Nikon camera is 450mm and on a Canon camera it is 480mm.