They’re not Glenn Bartley’s...but I’m still learning the craft of bird photography. So far I’m pleased with the 200-500, but I’m also recognizing its limitations. While f/5.6 is doable, it takes an extra bit of sharpening to get the feathers crisp. Lr’s new Texture adjustment is helpful as is Sharpening as with an Adjustment Brush. I must give credit to my wife - the real birder - whose keen eyes see everything flitting about.
All shot w/D800E on a tripod
Cardinal: f/5.6 @ 1/125, ISO 400
Kingbird: f/8 @ 1/400, ISO 400
Yellow Warbler?: f/5.6 @ 1/500, ISO 800
Downie Woodpecker: f/8 @ 1/80, ISO 400