Canon SLRs Lenses

I know the bigger the aperture the faster the shutter speed, but is there a technical name for such a lens? I want to get one that I can use in dim lighting conditions but don’t know what exactly to ask for.
Not a tripod or remote shutter release, got those already!

I know the bigger the aperture the faster the shutter speed, but is there a technical name for such a lens? I want to get one that I can use in dim lighting conditions but don’t know what exactly to ask for.
Not a tripod or remote shutter release, got those already!

Most 35mm film camera lenses have a screw thread on the inside of the lens housing at the front, which is used to attach filters or a sun hood. The diameter of this thread is usually marked on the front of the lens in millimeters, such as 49, 52, or 55, followed by an “o” with a diagonal slash through it. I need to know the name of this measurement. (It’s not “focal length”.)