Tonight I took out my small telescope and camera an took a few pictures of the moon, and also used a camera lens with the same focal length for comparison.
My small telescope is a Skywatcher 102 refractor which I bought as a cheap and light alternative to lugging around my 200mm reflector. It has a 102mm diameter and 500mm focal length equating to an f/5 lens. I also have a Sigma 150-500mm lens which is comparable, but higher quality. I wanted to see the difference between the cheap telescope and the expensive lens for astronomy so I took out the two for an evening with the moon.
The first advantage to the Sigma lens is that the lens has autofocus, while the telescope does not. The first immediate disadvantage of the lens is the slower speed and I cannot use any filters. All in all, I found the lens easier to use and got better results from it, however the telescope is a lot more flexible in that I can add filters, use barlow lens (for greater magnifications) and use it for eyepiece projection.
I think I'll stick to using telescopes for astronomy, but look at investing in a higher quality refractor.
Here are the two images for comparison.
More of my astroimages can be found on Perfect Astronomy.
My website and its content are free to use without the clutter of adverts, tracking cookies, marketing messages or anything else like that. If you enjoyed reading this article, or it helped you in some way, all I ask in return is you leave a comment below or share this page with your friends. Thank you.