600/4 VR + 1.4TC, D3, F5.6, 1/1250, 850mm, iso 1100, +0.7 exposure compensation
Winter can be long and cold in Iowa, but I look forward to my annual trip to Le Clair, Iowa to photograph Bald Eagles. Lock and Dam 14 is one of the best places to see and enjoy the national bird. If you time it right, there can be as many as 40-60 eagles fishing near the dam. The numbers vary depending on the shag population in the river. The fishing action can be as close as 20-40 feet. The highest eagle numbers are seen towards the end of January or early February.
Lock and Dam recreational area 14 in Iowa has the highest concentration of eagles. In the late afternoon with the sun behind you is the best time to photograph. Mornings are good from the Illinois side but the eagles are far away.
Long lenses are essential. A 300mm lens allows you to get a decent shot of near by fishing eagles and great over head flight shots as well. 400-600mm are also necessary for really good images. 500mm lens is ideal.
In general I would like to have a minimum shutter speed of 1/ 1000 sec to get a sharp picture of an eagle in flight. At around 1/800 of second, the wing tips tends to blur . In cloudy days, achieving 1/1000 of second can be a challenge. I usually set the camera to shutter priority and auto iso. In my D3 I set the range of iso between 200-1600. The camera will change the aperture first and then the iso to achieve the desired shutter speed.
Preserving the details in the wings without blowing the whites in the head can be challenging. Always check the histogram to make sure your exposure is correct. Try to get the histogram curve to your right as much as possible without blowing the highlights. You may have to add exposure compensation of 1/3 to 1 stop to achieve the desired exposure.