Name: Canon Macro Lens EF-S 60mm f/2.8 USM.
EF: Electronic Focus. All modern Canon lenses do this.
-S: Only works on newer, small (1.6x factor) DSLRs, which are the 40D, 30D, 20D, 20Da (astronomical), Digital Rebel XTi, Digital Rebel XT and the original Canon Digital Rebel.
USM: Ultra-Sonic Motor: The focus motor operates silently.
Focal Length: 60mm. On a 1.6x camera it gives an angle of view similar to what a 97mm lens would give on a 35mm film camera. See Crop Factor.
Maximum Aperture: f/2.8.Optics: 12 elements, 8 groups.
Diaphragm: 7 blades. Stops down to f/32. The in-camera indication stays the same while focusing. It doesn't read the effective f/stop, which gets smaller as you focus more closely. Beware using external light meters unless you know the correction factors. Used with the camera's own metering there is no problem, since it reads through the lens and compensates accordingly.
Filter Size: 52mm.
Close Focus: 8" (20cm) from the image plane (the back of the camera).
Working Distance: At the close focus distance there is only 3-1/2" between the subject and the front of the lens — less if you use filters. It is difficult not to block your own lighting and not to annoy living subjects. This is why I prefer the Canon 100mm macro, which at the same image size, gives you almost double the room with which to work.
Maximum Reproduction Ratio: 1:1 (life size).
Size: 2.867" diameter x 2.747" extension from flange (72.83 x 69.78mm),
Weight: 11.685 oz. (331.2g).
Hood: ET-67B
Introduced: March 2005