Some D600 + 24-70 f2.8 pictures. Is that IQ expected?

I will try to be helpful, but if you were "testing" the lens this is not a good way to do it. You have exposure compensation at 1/3 stop +, you are using a high ISO, and I see camera movement in the 1st picture. You have a great camera and a great lens but your post is puzzling. All of these facts hint that there might be others.

To answer your question:

1-Yes, this is a great combination

2- Your image quality is lacking - but not because of the camera or lens

Read a little more. Then practice. Repeat. You seem to have a good eye, but your basics need a little polishing. Keep working at it. You will get there.

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Steve Bingham
www.dustylens.com
www.ghost-town-photography.com