100-400 with 1.4x? American Golden Plover - ANWR

American golden plover, Arctic National Wildlife Refuge, Alaska. Canon 5D Mark II, 100-400mm f/5.6L IS w/1.4x, 1/250 xec @ f/8, ISO 400

Crop of original frame. Canon 5D Mark II, 100-400mm f/5.6L IS w/1.4x, 1/250 xec @ f/8, ISO 400

During a raft trip down the Marsh Fork of the Canning river, a long day hike up into the mountains led me to some vociferous plovers that nest in the region. While I have a number of Plover photos that I consider better than this one, I did photograph the bird because of the specific location in the ANWR. But what is surprising to me and the reason I’m including it here, is that I did a little experiment and shot the picture with a lens configuration that I don’t normally use. Generally, I would have my trusty 500mm lens but I hiked 4000 vertical feet, so I packed light and chose the 100-400mm lens for versatility. 400mm is not really powerful enough to pull in many birds, and just for grins I thought I’d try it with a 1.4x for a little more reach. The 5D Mark II camera will not autofocus with this lens configuration because the aperture is f/8 at the widest, introducing a challenge of its own. However, I was very, very surprised at the sharpness of this image, all things considered. The camera and lens were mounted on my tiny gitzo tripod, and shot in less than ideal conditions. There are obvious limitations to this configuration, but some obvious benefits also, and based on this real-time-field-test, I’ll be doing some more experimenting with that set up in the future. I’ve included a crop of the original capture to show the sharpness of the image.