Details on the Canon EF-S 17-85mm f4-5.6 IS USM zoom lens with Image Stabilizer

Overview (As per Canon)

Equivalent to a 28-135mm lens, this new EF-S lens brings true wide-angle to tele coverage to EOS 20D and Digital Rebel shooters. It has Canon's Image Stabilization system, allowing safe hand-holding at speeds up to three stops slower than otherwise possible. And of course, it's optically optimized for digital SLRs. A ring-type USM means both fast and silent AF, as well as full-time manual focus when in the AF mode.

Features
- Compact, lightweight design with a 5x zoom ratio
  (28 to 135mm equivalent)
- Excellent optical quality: Aspheric element with
  two Aspherical surfaces utilized
- Close-focusing to 1.15 feet -- at 135mm, fills the frame with subject 3 x 4.4 inches
- Ring-type Ultrasonic motor for superior AF performance; allows full-time MF
- Image Stabilization extends the lens's usefulness in low-light levels
- Circular aperture design -- natural highlights, even stopped down two stops
- Non-rotating front element; lens length does not change during zooming
- EF-S lens mount -- exclusively for EOS 20D and Digital Rebel bodies

Specifications
Focal Length & Maximum Aperture 17 - 85mm; 1:4-5.6
Lens Construction - 17 elements in 12 groups
Diagonal Angle of View - 78° 30' - 18° 25'
Focus Adjustment - Inner focusing system, with focusing cam
Closest Focusing Distance - 0.35m - 1.15 ft.
Zoom System - Ring USM
Filter Size - 67mm
Max. Diameter x Length, - 3.1" x 3.6". / 78.5 x 92mm
Weight - 16.8 oz / 475g

Diving with the Canon 20D camera

We use the above Canon leans and the Ikelite watertight case
We have chose the Ikelight underwater camera housing for our Canon EOS 20D digital camera. Follow the link to read more about this high quality product!

Our small "Very portable" digital camera
We also use or smaller Canon PowerShot SD700 IS Digital camera

Other Canon camera equipment we rarely use:
1 - Canon SpeedLite 580EX Flash
2 - Canon BG-E2 battery grip