The low shutter speeds mean that commentary on sharpness can be noted, but not considered definitive.
The forest shots were shot handheld in part to assess the VR functionality. Nikon claims “up to 5 stops of image stabilization”, which means that 1/40 second should be 1/1250 equivalent or so, which the outing proved to an unjustified claim, even using my very best technique and really taking my time even for my own heartbeat. Still, the VR is extremely effective over not having it; with a ~50% or so success rate at absurdly low speeds of 1/40 - 1/80 second at ~200mm. As a very rough estimate, I deem it good for 2-3 stops for critical sharpness and 4 stops for viable images (as very rough estimates).
I really enjoyed shooting the 70-200mm f/4G ED VR in the forest; the lens is small and light enough not to make a nuisance of itself as with the ƒ/2.8 model, and the zoom range allows selectively picking out items for “close examination” without the focal length shortening / working distance issues as with the ƒ/2.8 model.
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