Nikon_70-200_VR_Review

Nikon 70-200 mm AF-S, VR Review

Part 3

Image Quality

The image quality from this lens is stunning - it renders details extremely sharply with good contrast and it's reproduction of out of focus areas of the image is great. The sharpness allows generous crops to be made with little effect on image quality.

The four images below demonstrate the great combination of sharpness and smooth out of focus rendition achievable.

			This is an example of the way this lens can be used to achieve an unusual composition by homing in on one element, creating interest in an otherwise ordinary scene. The fine detail is again impressive and out of focus detail is very subtly rendered
	For images like this the range of the 70-200 allows for a close crop of an individual element in a scene. The sharpness is fantastic and in this instance (with the lens set to 200 mm at f/4) so is the bokeh

			Another example where sharp focus and smooth out of focus rendering have delivered great creative control
	The range of the zoom allows great scope for following action when you can't get as close as you might like and delivers razor sharp results

	Image Quality - Wide Open

	I've traditionally avoided using my lenses at f/2.8 with my D200 due to adverse quality when wide open but this is far less of an issue with the 70-200. Images shot at f/2.8 are perfectly acceptable and any slight softness is easily recoverable with minor post process sharpening. Image 1 (right) of hound trailing illustrates the benefit of having an f/2.8 lens over a slower lens of a similar focal length. Although VR will counteract camera shake with slower shutter speeds - for fast paced action like this there's no substitute for a wide aperture to freeze the motion in the scene. Under many circumstances narrow depth of field can be desirable but often this aspect of a lens is compromised on a DX sensor due to the smaller sensor area increasing depth of field. As a consequence, when trying to maximize selective focus, shooting at f/2.8 is necessary and strong performance wide open is again important.

			Image 1. Taken wide open at f/2.8 this image demonstrates the degree of sharpness achievable at f2.8 with a fast moving subject

	Image 2. 100% enlargement from Image 1 above taken at f/2.8 and 1/350th of a second, no sharpening applied, only black and white conversion. In this type of image there's likely to be a degree of motion blur due to the fast moving dog and the shallow depth of field also restricts the amount of the image in focus. Nevertheless the hounds eye's are acceptably sharp, as are the stationary grass stems to the right. With minimal sharpening this is a very usable image

Fall Off

The 70-200 is far less susceptible to fall off in the corners compared to my previous 80-200 and demonstrates virtually no chromatic abberration thanks to the newer optical design (based on my experience with a DX body). The issue of resistance to corner fall off is of course less of a concern with cameras with DX sized sensors due to the 1.5 x crop factor applied. However, with cameras featuring FX sensors, it is likely that this advantage will become increasingly important to digital users as it always has been for film use.

Lens Bokeh

Rendition of out of focus areas of the image is good throughout the zoom and aperture range; offering scope to blur distractions with a wide aperture or hold onto background detail with a narrower aperture setting. The thistle images below were taken at a focal length of 200 mm (equivalent to 300 mm with a DX sensor) and demonstrate the bokeh throughout the aperture range from f/2.8 to f/22.

The lens features a rounded nine bladed aperture. As a result out of focus areas of the image transition smoothly with good bokeh and out of focus highlights are recorded as pleasingly round elements in the image.

	f/2.8		f/5.6		f/11		f/16		f/22

	Click on the thumbnails above to go directly to the enlarged version of each shown below

			f/2.8

			f/5.6

			f/11

			f/16

			f/22

The bokeh comparison images above show the out of focus rendition characteristics of the 70-200 lens - they also demonstrate the level of control that can be achieved over depth of field at a given focal length. The degree of detail captured in the out of focus background elements can be very precisely controlled for creative effect and due to the VR small apertures can be used without slow shutter speed impacting on image sharpness - provided that subject motion does not cause blur. In the thistle images above shutter speeds range from 180th at f/2.8 to 1/8th at f/22.

Flare and Ghosting

One area where this lens does show a weakness is its succeptability to flare and ghosting. This is understandable given the number of glass surfaces in the optics. Despite the 5 ED glass elements and the use of Nikon's Super Integrated Coating to optimise performance flare can be an issue.

The two images below show a very similar view of a raspberry growing in a hedgerow, backlit by low evening sun. Between making these two exposures I moved very slightly toward the sun in the upper right of the frame. The result shows typical performance in this situation, with the subject obliterated by flare. This isn't all bad though - you simply have to establish the ground rules with this lens. I know that flare is a high risk and therefore guard against it. Also, as this example proves when flare is an issue it's so significant that you're immediatly aware and can recompose or readjust position to prevent it.

	A backlit situation with the lens facing almost into the sun
			A slight recomposition and the effects of flare are clear