Great techniques for low-light astrophotography

1 Exposure blending

This is a method of combining multiple photographs taken at different settings together in software to create a perfectly exposed final image. Photographs captured with the settings needed for pinpoint stars often result in a very dark and out-of-focus foreground. Separate shots with settings appropriate for the foreground can be captured then blended with the sky shots, to make a final image that has plenty of detail in both the sky and the foreground.

2 Sky exposures

When I use this term, I am referring to the photographs taken that capture the stars as pinpoints or with very small trails (as opposed to full star trails). The foreground is still in the frame, but it will often be very dark depending on the ambient light of your shooting location.

3 Foreground exposures

This term refers to images taken with settings to capture a brighter foreground. These usually include a much longer shutter speed than would be possible for the stars.

4 Focus stacking

This combines multiple shots taken at different focus distances together in software to create an image with more depth of field (more in focus) than a single photograph. This is often necessary to get the entire foreground in focus, particularly when, at night, we are using apertures such as f/2.8 to let in a lot of light, but at the cost of less depth of field.

5 Star stacking

This is a technique that involves capturing multiple photographs, with settings appropriate for the sky to capture sharp stars and reasonably small star trails, then blending them later using dedicated star stacking software, to give you an image with much less noise than would otherwise be present in a single shot.