Manual Exposure Cheatsheet - Master manual photography with your digital SLR. We figured it was only appropriate for our first post to give something back. This exposure cheat sheet covers the basics of mastering manual exposure with a SLR camera.
Lenses with longer focal lengths are slower (have smaller maximum apertures) than wide-angle lenses. That's why photographers mostly use wider lenses in low-light situations -- they gather more light and help create sharper images.