Don't you love when things work out when the conditions are not stellar? Chances are, if it wasn't windy, you might not have taken the pictures of the seagulls. This way, not you can perfect it.
I really like the first, third, and fifth ones. The close us is cool, just because I can count his feathers. That is a win. The others show off the amazing eye the lens has and capture it. I have a 400 that is heavy also, It is huge and heavy, so don't like to lug it, especially when I am on foot.
Then the tripod. LOL I must be getting old. Great shots and I am glad you are getting out and trying the new piece. :)
Have a great day!
Yes it did work out well and happy to test it in birds looking forward to going birding in spring with my big lens