I just laid my hands on an EF 400 DO f/4 IS II, and coupled with an EOS 7D MII and an EF 1.4x TC III, it is a very impressive combo for capturing birds in flight (BIFs) - light hence hand holdable, very sharp with a 1.4x TC III even wide open, long enough (896 mm angle of view), extremely fast focusing and with a fast frame rate (10 fps).
To get to around 900 mm AOV before, I had to use tripod-based combos (1D MIV + 500 f4 + 1.4x TC, or a 7D + 400 2.8 IS + 1.4x TC). This severely limited my mobility and reduced my birding opportunities. With my new light combo, I can take long hikes and shoot hand held, increasing my bird shooting possibilities significantly.
Here are some in-flight images of this large migratory water bird, among the first bird shots I've taken with my new rig.
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Great Egret (Egretta alba, migrant)
Habitat - Uncommon in a variety of wetlands from coastal marshes to ricefields.
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Shooting Info - Sto. Tomas, La Union, Philippines, November 7, 2015, EOS 7D MII + EF 400 DO IS II + EF 1.4x TC III, 560 mm, f/7.1, 1/2000 sec, ISO 320, manual exposure in available light, hand held, near full frame resized to 800x450. |
High res 1920 x 1080 version
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Shooting Info - Sto. Tomas, La Union, Philippines, November 7, 2015, EOS 7D MII + EF 400 DO IS II + EF 1.4x TC III, 560 mm, f/6.3, 1/3200 sec, ISO 320, manual exposure in available light, hand held, uncropped full frame resized to 800x533. |
High res 1500 x 1000 version