Things are still a bit messy on the blog as I imported it from my old website. Links may be broken. I’m working on it! Thanks for your patience.
What is fast glass?
This post will explain what lens speed is all about. Lenses all have a maximum aperture. The maximum aperture is the widest opening the lens can have. The wider the lens opening the more light it will let in to the camera sensor. Here is a graphic representing apertures:
Should I use a flash or get a fast lens?
At some point after you've purchased that entry level sub $1000 dSLR kit with a couple of consumer grade zoom lenses, you're going to want a faster, sharper lens. By faster I mean one with a larger f-stop than the typical f3.5 you're getting at the wide angle setting of the lens in the kits. Remember, a faster lens lets in more light, so you can you can use a faster shutter speed. That's where the term comes from.