Identification
There is a metal plate screwed onto the top of the tripod mount which has the lens model on it. The label should have "CANON LENS EF 600mm 1:4 L IS USM" on it.
Technical Specifications
General:
- Focal Length: 600 mm
- Maximum Aperture: f/4
- Minimum Aperture: f/32
- Closest Focusing Distance: 5.5 m (18 ft)
- Maximum Magnification: 0.12 x
Construction:
- Lens Groups: 13
- Lens Elements: 17
- No. of Diaphragm Blades: 8
- Focusing Adjustment: Inner focusing system with USM
Physical:
- Lens Mount Type: Canon EF
- Filter Diameter: 52 mm Drop-In
- Maximum Diameter x Length: 168 x 456 mm (6.6 x 18.0 in)
- Weight: 5,360 g (11.8 lbs)
Accessories:
- Lens Cap: ET-185
- Lens Hood: ET-160
- Case: Lens Case 600
- Magnification - Extension Tube EF12 II: 0.14 - 0.02
- Magnification - Extension Tube EF25 II: 0.17 - 0.05
Source: Canon Camera Museum & Canon Lens Specifications