ML549325851
投稿者
日付
場所
- 年齢と性別
- 成鳥オス - 3
視聴覚メディア・ノート
Wave action makes the middle bird look largest and the left bird smallest in this photo. Their order has not changed.
観察結果の詳細
The reported three scaup were still out on the middle of the lake, but difficult to speciate in the bins given the distance, low light, and choppy surface action. However, one turned into a Lesser, then maybe a second one, and I decided to wait and review photos before assigning identities. Photos later showed all three were Lesser. In the first photo, the peaky crown shape is evident in the center and right birds, but the leftmost scaup has its neck retracted and. is leaning slightly to his right, affecting the apparent crown and bill shapes. The second and third photos were added because they show how the wave action affects the apparent size of the birds without any change in the order of the trio. Comparative measurements of the length of the individuals is all the same (a Greater ought to be about 7% longer than a Lesser when measured). When the sun poked through briefly we detected a purplish sheen to the head color of all three birds. The head color is not a diagnostic field mark, but usually, in sunlight, a Greater Scaup male shows a greenish sheen instead. The series of photos of the scaups show than none of them consistently shows the flatter, slightly rounder-arced crown expected for a Greater.
テクニカル・インフォメーション
- モデル
- Canon EOS 5D Mark IV
- レンズ
- EF400mm f/5.6L USM +1.4x
- ISO
- 1000
- 焦点距離
- 560 mm
- フラッシュ
- Flash did not fire
- Fストップ
- f/8.0
- シャッタースピード
- 1/500 sec
- 大きさ
- 1662 pixels x 1108 pixels
- オリジナルのファイルサイズ
- 211.18 KB