There is probably no other genre where light is at more of a premium than astrophotography, where ultra-wide apertures, high ISOs, and specialized equipment are the name of the game. This fascinating video shows what two professional astrophotographers were able to accomplish when limited to a very slow kit lens for their work.
Coming to you from Astro Backyard, this great video follows two photographers as they shoot the night sky using a Canon EF 75-300mm f/4-5.6 III USM lens. The 75-300mm f/4-5.6 is anything but a fast lens and not especially sharp either, and in a genre where the aperture of choice is usually f/1.4 or something similar, it presents some real difficulties for both photographers. However, despite the already narrow maximum aperture, you will see they stop the lens down a bit further a bit to compensate for its softness. Of course, they use German equatorial mounts, which compensate for the Earth's rotation by rotating the camera and lens in a plane with an axis to that of the Earth's to allow for longer exposures, but with such a slow aperture, it is still a significant challenge. Check out the video above to see how they did!
So at f/5.6 they're shooting faster than most dedicated imaging refractors which usually clock in at f/7. There are dedicated astrographs as fast as f/2 but typically f/4.5 - f/7 is where most scopes are. Astrophotography can be a challenging and really (really!) expensive hobby but these guys picked a pretty challenging target and they both did really great. The other factor to this video is that they acquired all this data in one night. My version of this target was shot over 2 nights and was about 7 hours of data.
For what it's worth- I think Trevor did a better job with his editing but I like the way Nico framed his shot.
I shot meteors with a 24-70mm sony kit lens, no idea what I was doing either lol. I just googled "astrophotography settings" and went to town.