3 Way Holiday Camera Shootout Part 3, Lenses

 

Introduction  Lens quality is a key determinant of overall picture quality. No camera can perform better than the lens mounted onto it.

Superzoom Lenses  These have the advantage of versatility and for most purposes, remove the need for changing lenses. But they have a complex design with many elements and at the consumer level as with the three lenses in this review, are built to a price. This means they do not deliver the same optical quality as less ambitious zooms and are more prone to sample variation and decentering.

 

1. For the D5200 DSLR, we have the Nikon AF-S Nikkor 18-200mm f3.5-5.6 G II DX ED VR. Yikes, just the name of the thing takes almost a line of type. This is the MkII version of this lens, dating from 2009, although it has the same optical construction as the MkI version. This is a solid feeling, apparently well built lens with double extending barrel. It is the only one of the three to have  physical distance scale, located  beneath a transparent window in typical DSLR lens style. This means you can manually set a chosen focus distance by scale.

It zooms smoothly enough. The external barrel is bristling with switches for Zoom Lock, AF/MF, VR On/Off, VR Normal/Active. The zoom does creep without the lock. There is audible clicking and whirring from the lens as it focusses. Although by no means a large or heavy lens by DSLR standards it feels much more bulky and weighty  in the hands then either of the other two lenses.

It appears to be a parfocal design, which means it stays in focus while zooming.

2. For the G6 we have the Lumix G Vario 14-140mm f3.5-5.6  Asph Power OIS. This is a new for 2013 and completely different version of the Lumix 14-140mm lens. The original version dating from 2009 was larger, heavier, had a smaller aperture range of f4.5.8 and cost more on introduction. Early reports indicate the new version is also optically superior. Everything improved, Wow!  This is the lightest lens of the three and is only 4 mm longer than the Nikon 1 lens. It has a single extension inner barrel with the smoothest zoom action of the three lenses and no zoom creep. It has an OIS On/Off switch on the outer barrel. Despite it's light weight it feels well made with no detectable free play of the barrel, unlike the other two lenses which do exhibit a little movement.

It is a varifocal design which means it has to be refocussed after zooming.

3. On the Nikon 1 V2 we have the Nikon 1 Nikkor 10-100mm f4.0-5.6 VR. this is also a second version of the Nikon 1 superzoom theme. The original Nikon 1 10-100mm PD superzoom is a much larger and heavier lens with 72mm filter size, designed, I believe mainly for motion picture duties. Like the other two lenses this one feels very well made and operates smoothly although the double extension inner barrel zoom action does have a little hitch in it's progress about half way through the range. This lens is of semi collapsing type to reduce it's closed length. To extend the lens for use you press a button on the lens barrel then twist the outer barrel until it clicks. This action also switches the camera on, ready for action. This might sound a bit clumsy but in practice works well and soon becomes second nature. Unfortunately this lens does not have a manual focus ring just as all but one of the Nikon 1 lenses at the time of writing lack a manual focus ring. OOOps !! Did it not occur to the Nikon product development people that enthusiasts might be interested in a system camera which can do predictive AF at 15 frames per second ???

This is also a varifocal design.

 Comment on DimensionsAs you would expect, the DSLR with the largest sensor needs the biggest lens and the Nikon 1 V2 with the smallest sensor has the smallest lens. However the two MILC lenses are quite close in dimensions, while the jump up in size and mass to the 18-200mm is more apparent in use.

The Minimum focus distance is measured from the subject to the sensor plane.

Mechanical function  Each lens has optical image stabilisation which appears to work well. My subjective impression is that VR in the Nikon lenses appears to stabilise the viewfinder image more effectively than OIS in the Lumix.

Mirror Slap and Shutter Shock  I ran numerous systematic tests for these unwelcome phenomena, using shutter speeds from 1/10-1/400 second. In this range I found no evidence of blur due to mirror slap with the D5200 (mirror down) and no evidence of blur due to shutter shock with the D5200 (Live View) or the V2 with mechanical shutter. Nikon's engineers appear to have tamed shutter shock quite effectively.

With the Lumix 14-140mm on the G6 I did find evidence of shutter shock in the shutter speed range 1/100 to 1/160 second with the mechanical shutter.   There was no problem with the E-Shutter in use.

Decentering  With so many lens elements it is not surprising that they are not always assembled with absolute precision. Each of the lenses in this test showed some evidence of decentering, particularly evident at the long end in each case but also apparent at the wide end of the 18-200mm.

Manual Focus  There are marked differences in manual focus operation between the three kits.

Worst is the V2 which can do MF but the procedure is so convoluted and the  determination of In/Out focus so difficult, that the whole exercise is hardly worth the bother. You have to press the Feature  button, scroll to the Focus icon, press OK, scroll to MF, press OK again, then rotate the Multi Selector to change focus. Press the OK button again  to zoom in and rotate the Command Dial to zoom some more.

With eye level viewing the D5200 allows FTM (Full Time Manual, enables manual focus while autofocus is active).  This works well at the long end of the zoom but at the wide end it is almost impossible to pick the in/out  focus transition and there is no focus assist (no peaking, no electronic zoom). That is just a characteristic of  typical APS-C optical viewfinders. You get what you get.  In Live View the D5200 also offers FTM with the option to zoom in using the Zoom In and Zoom Out buttons. However it is still very difficult to evaluate the In/Out focus transition at wide angle lens settings. In addition you have to be very dextrous or better, use a tripod, to juggle the Zoom In/Out buttons while pressing the shutter button and operating the manual focus ring while supporting the camera and lens.

By far the best manual focus arrangements are to be found in the G6/14-140mm. First you have FTM with eye level or monitor view and it works the same with both. Just acquire AF with the AF/AE Lock button or half press the shutter button and simply start turning the focus ring on the lens. The view zooms in automatically and can be zoomed further by turning the rear dial. Focus peaking springs into action and makes picking the in focus position easy.

Or you can go to the Q Menu while using eye level or monitor view and select MF. This is easily done by feel without having to look at any of the buttons. Either way the process is fast and accurate.

The only thing you don't  get with any M43 camera to date is the ability to preset a chosen distance by scale.

 Note that these results are valid for the lens samples which I tested. Due to sample variation different results could be given by other copies of the lenses.

Resolution   I ran many tests for resolution using a test chart and many real world subjects of different types, photographing the same subject with each kit side by side. I won't bore you with the minutiae of my findings but here is a summary of the results:

The D5200/18-200mm was best or equal best in the center at all focal lengths [except for issues with focus variation, see below]. This kit delivered the worst edge/corner performance at all focal lengths.

The G6/14-140mm was equal best (or better when the 18-200mm did not focus correctly) with the 18-200mm in the center on several of my test runs and was best at the edges and corners at all focal lengths on all test runs.

The V2/10-100mm was equal to the 14-140mm in the center on some runs and second to the 14-140mm at the edges and corners on most runs.

Overall the Lumix 14-140mm had the best all round resolution taking into account center, edge and corner sharpness at all focal lengths.   Next was the V2/10-100mm and  last was the D5200/18-200mm, let down by poor edge/corner performance.

Flare  Each of these lenses is prone to flare with the sun in frame and at or near the frame edge. This is normal for this lens type. In use each should be protected from sun on the front element, if possible.

Chromatic Aberration (CA) and Purple Fringing (PF)  These issues are quite common with superzoom lenses. The G6/14-140mm utilises automatic, in camera CA correction which is very effective to the extent that CA in photos from the G6  is almost nil. There is some residual PF in some very high contrast scenes.

The D5200/18-200 is very prone to CA and PF.  For RAW files there is a Profile for this camera lens combination on Adobe Camera RAW (ACR) (or Lightroom) which rectifies the CA quite effectively.

The V2/10-100mm is also quite prone to CA and PF but there is no profile at the time of writing. CA can however be removed manually in ACR.

Distortion  The 18-200mm and 10-100mm lenses have plenty of barrel distortion at the wide end. This is corrected with the ACR profile for the 18-200mm. The 14-140mm probably also has substantial distortion but if so it is largely corrected automatically in a M43 camera.

Focus Variation All autofocus systems are prone to error with some subject types. These are described in the D5200 Reference Manual although I couldn't find much about this in the G6 or V2 Manuals.  In the many hundreds of photos which I made during the comparison testing process, I found some frames incorrectly focussed, as indicated by center of frame unsharpness. The proportion of these not-quite-in-focus frames was higher with the D5200/18-200mm in both eye level view (PDAF) and monitor view (CDAF).

Summary   By the time my lens tests were complete a clear ranking had become apparent.

Overall the Lumix 14-140mm is the best lens of this trio, followed by the Nikon 1 10-100mm, with  the 18-200mm bringing up the rear.

Comment on the rankings  The Lumix 14-140mm is the newest design of the three, the Nikon1 10-100mm not quite so new but recently released. The 18-200mm is by several years the oldest.  It does appear that the design and manufacture of consumer zooms has improved considerably in the last few years.

And to finish on a little aphorism: "Dont judge a lens by it's size or price".