Bald Eagle

This guy was hanging out in our backyard. He was watching the turkey vultures feeding on a dead animal in the woods. Two bald eagles joined the vultures as they fed on the carrion. 
Shout out to my husband who spotted the eagles. I tried using my Nikon VR 200-500, but it did a horrible job. I used a ten-second delay for the shutter and disabled the VR to prevent camera movement but it still added a weird grain to the photo (extra.) This lens has been the worst. I wonder if there is something that I am doing wrong, or if the lens itself is faulty.
The main is shot with the kit zoom that came with my D7500 using the ftz converter.