I'm no wildlife shooter but I do know keeping the shutter speed at one-and-half to two times the focal length is critical to getting consistently sharp shots; it's a "rule of thumb" I adhere to slavishly when I'm shooting a DX body. Yes, I know... This is going to drive your ISO way beyond the ISO280 those shots were taken at but here's the thing: Noise you can clean up in post processing; a shot with motion blur is a whoooole nuther story. You might be able to open your aperture a bit from that f/8 you're using as well too help compensate.
One other possibility... The latest version of Photoshop has a "Motion Blur" filter you can try; though I've found it's a bit hit-or-miss, when it does "hit" it can do miraculous things. If LR has the filter, it's definitely worth trying.
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Well just for fun I took what I thought was one of your less sharp shots from your post and "corrected" it using the Shake Reduction filter (that's the correct name for the filter I was talking about earlier). At the default setting I thought the effect was a little too strong so I opened a new adjustment layer, used the Shake Reduction filter again and then reduced the opacity of the adjustment layer to 80%; no other adjustments were made. Here's what I got for my effort...Thank you for the input. I figured a shutter speed of 1:1250 would be fast enough and f8 is the sharpest aperture on this lens. I will try higher shutter speeds and see if subject motion blur is the problem. LR 6, which is what I have does not have the Motion Blur filter, Adobe only issued it for LR CC.
Well just for fun I took what I thought was one of your less sharp shots from your post and "corrected" it using the Shake Reduction filter (that's the correct name for the filter I was talking about earlier). At the default setting I thought the effect was a little too strong so I opened a new adjustment layer, used the Shake Reduction filter again and then reduced the opacity of the adjustment layer to 80%; no other adjustments were made. Here's what I got for my effort...
Your Original:
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View attachment 173288
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With Shake Reduction:
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View attachment 173289
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Definitely go for a higher shutter speed to start with. Freezing motion can be tough @ 600mm when there's so many movement factors at play outside of your already moving subject. Maybe try ISO 400-800 and a shutter speed in excess of 1/2500 just to see if that helps you out. What kind of focus tracking are you using also, AF-C D9?
I'm a Photoshop sorta guy; I don't really know Jack about Lightroom. Upping the Contrast a little helped the image as well I think, though you don't see that in my post because I wanted you to see the difference the Shake Reduction filter made all by itself.Thanks Paul, a definite improvement. Did you use PS for that or LR CC. It would seem I do need a faster shutter!