I will do a test this morning at 600mm at f6.3 (wide open) and post it later.

Here is a shot @ 600mm, f11, 1/1000 ISO-400 using a D750.
The sweet spot for the lens is f11. I wouldn't shoot it wide open at that distance because I want to get a sharp image.
This was hand held with the normal stabilization.

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I had the first version and traded in for the G2.
It is much sharper at 600, utilizes the TAP adjustment USB system, has a much better foot on the collar that has the Arca mount built in and 2 crew holes, 3 position stabilization, locking position at every focal length, and focuses closer (7.2 ft).
I love it.

Shot @ 600mm 1/400 f10 ISO-1000 D750

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I would agree with nimbushopper, the Circle B ranch in Lakeland is a great place for wildlife shooters. If you get down to Palm Beach County, Green Cay and Wakodahatchee Wetlands are great too.

I've used that lens and camera combination and it works great. The 70-200 f4 is one of the sharpest Nikon zooms and the D7200 has no filter anti-aliasing filter, resulting in very crisp images. The DX crop factor makes this camera and lens combination equal to a 105-300mm lens- great for close birding (lot of feather detail).

Wood Stock c/u shot with a Nikon D7200 and Nikon 70-200 f4 @ 1/800 f6.3 ISO 500 @ 200mm

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Thank you

I normally use this lens with my D7200. I adjusted the lens itself with the TAP set up for the D7200. See the attached image. The lens is very sharp on that camera. I should try to do the in camera AF fine tune on the D750 with the lens and see how it works. (TAP is Tamron's USB fine tune adjustment hub and software)
Thanks for your input.

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This photo of a female and male Wood Ducks was shot at Boynton Beach, Florida in a residential lake with a Nikon D750 and a Tamron 150-600mm G2 @600mm 1/2000 f7.1 - hand held
This photo was slightly cropped.

female and male Wood Ducks

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The 70-200mm f4 is a great travel lens if you don't need the wide side. Ultra sharp, only a small amount of distortion, light and small, N coating and VR. I love this lens.

http://www.kenrockwell.com/nikon/70-200mm-f4.htm

I have the Nikon 1.7-TC (it is discontinued, but you can still find them). I don't us it often. I bought it to go on my 70-200 f4 (a super sharp lens) when I travel with my D7200. It gives me an effective reach of 178.5-510mm.
I was expecting it to be OK, but not great. To my surprise, it is very good (I am very critical). You will need to adjust your AF Fine tune adjustment for your lens combination in the camera. The camera will the remember it as that lens and TC combination. If you use it with a sharp lens you most likely will be vey happy with it. Here is a link of a shot of a Sora I took with this combination:

https://www.flickr.com/photos/129992705@N03/32219065855/in/datetaken/

I have the Tamron 150-600 G2 and I love it. It's light, sharp and focuses very close (7.2 ft). I had the first version and this is sharp throughout. The older one was slightly soft at 600. This lens is compared to the Sigma Sport, which is heavy, cost more and doesn't focus as close. Tamron also has a 6 year warrantee.
Here is a link with a comparison of the Tamron 150-600 g2 vs. Sigma 150-600mm Sport.
The Nikon is 200-500 and heavy and is inconsistent. Some are good and others aren't sharp.
https://www.youtube.com/watch?v=Gjxae68EGn0
Also, both the Sigma and the Tamron(TAP) have attachments to do an auto fine tune adjustments and updates online, Nikon doesn't have that feature.

If you are using a Mac and you back up daily, go to:
Users/ (you will see your user name) /Pictures/Lightroom/Backup/ (find the latest date and open the folder and click on the zipped file and it should restore your Lightroom settings- be careful, because it will restore to your last save!

I think it isn't the shutter, it is the hard mirror slap that is making the load sound.

Excellent answer.

Shot with a Nikon D7200 and the Tamron 150-600 G2 420mm at 1/200 @ f11 ISO 320 hand held

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