Tuesday, October 17, 2006

A love hate relationship with 2x extenders

If you have ever seen the media area at a professional sporting event then you have seen Canon's super telephoto line up: the 400 f/2.8 L IS USM, 500 f/4 L IS USM, and 600 f/4 L IS USM. These big white guns retail around $9400, $8000, and $11000 (CDN) respectively. At these prices the amateur photographer can only dream, and I do, of owning such glass.

The "budget" super telephoto:

So what are the options when you need (err.. want) a 400mm reach and your lotto 6/49 ticket is a not winner? This depends on your current lens collection. When I first asked myself this question I had (and still do) a Canon 70-200 f/2.8 L USM
, a 17-40 f/4 L USM, and a 50 f/1.4 USM.

70-200 + 2x-extender
At the time and solely for financial reasons I decided to go the 2x-extender route. This was getting the maximum reach for the minimum buck. Looking for the best deal I purchased a used Canon Mk I 2x-extender off ebay with large expectations given that my 70-200mm f2.8 L is tack sharp and produces excellent colour.

In the field:

It is not bad but not that good either to the point that I rarely use it now. The 2x-extender has a large impact on sharpness with the 70-200mm f2.8 L, even when you are stopped down to f8 to f11. This lack of edge contrast (sharpness) takes the "pop" out of the 70-200mm.

Lady lion
Lady lion
1/800, f/7.1, ISO 400, 400 mm

70-200mm +2x-extender, hand held

Chiriya III
Chiriya III
1/640, f/9, ISO 400, 240 mm

70-200mm + 2x-extender + tripod

The above photos are definitely "acceptable" but required a fair amount of sharpening and post-processing. One advantage of the 70-200mm + 2x-extender combo is its minimum focal distance at 1.5m versus the typical 3m of the other 400mm options. This means that you can fill the frame and get tighter shots. For example this hummingbird was about 2 meters away.

1/125, f/5.6, ISO 400, 400 mm
70-200mm + 2x-extender + tripod

The luminous landscape has some posts on Canon 2x extenders as well:

400 Vs. 200 with x2 converter

100-400 vs 70-200 with 2x extender

100-400 vs 400 prime

mk I vs mk II canon 2x extender>