As I noted in last week's post, I have always found DXO's Sensor Scores to be a very reliable guide to the performance of a camera sensor. Their lens scores, however, are necessarily less comprehensive. 

In brief, this is due to the fact that no lab-based test can give you the skinny on the full complexity of a lens: factors such as field curvature (and the way it changes with focal length, focus distance and aperture), tendency to focus shift, efficacy of VR systems, quality of bokeh, performance of the optic at 'further than lab test' distances - all these things mean that a lens that tests well on DXO can be a somewhat different beast in the field. And the truth is, the ones that test well are sometimes a little less good in real life.

Before I start, it is worth noting that the great bulk of my experience is on the D800e rather than the D800 - and this can make a very significant difference. Roger Cicala at LensRentals was surprised to find, for example, that the Zeiss Makro Planar 100mm T* f2 lens performed so very much better on a D800e than he had expected, having tested it on a D800. It is also worth noting that Roger's view on build quality can put a different gloss on lab results too: he has said of one of the 'upstart' brands that, great though the performance of their most famously good lens is, a look 'under the hood' made him doubt that it will stand up to long term use as well as some of the more established brands.

To The Meat

I will generally include the 'top three' in each category other than where I own one lower down the list that I think deserves more consideration . I don't include DXO's detailed results - this piece is intended for readers who have already read their excellent series of articles and are seeking further opinions based on a wider range of real world factors. Note that the ranking DXO has allocated is based on their DXOMark scores, and these include Perceptual MP (perceived sharpness), Transmission, Distortion, Vignetting and Chromatic Aberration. My preferences tend to favour lenses with high sharpness and low chromatic aberrations. I am somewhat forgiving of distortion if it can be 'fixed' well in post, and transmission and vignetting generally don't bother me unless egregiously poor...

I say: I agree, but they really need to test the Nikon 70-200 F2.8VRII because clearly the choice is between it and the new F4 optic. IMHO the F4 is more useful. It has the newer VRIII which is worth an extra stop, making it effectively as fast as the F2.8 lens unless you really need extreme bokeh or ultimate action-freezing ability. I have had both, and the F4 version on the D800E is at least as good as the F2.8 VRII version, doesn't lose focal length to 'breathing' at close range at the longer end, and is smaller and lighter, by a big factor. Not weather sealed, though.

I say: I agree that the 24-70 is the best choice overall but they need to include the newer Tamron, which may not be optically quite as good (in my experience) but it's a pretty close call and it has stabilisation, and is smaller, lighter and cheaper. It's also important to be aware that the winning lens here, the Nikon 24-70 F2.8, is not very impressive at the widest setting.

I say: unless you are planning on shooting a lot of architectural work, I would choose the Samyang. It is the sharpest lens here, and that sharpness reaches the edges and corners very nicely. It gets marked down a lot due to fairly strong and complicated distortion BUT that actually doesn't matter for most subjects and when it does matter, it can be easily cleaned up in PTLens, without losing much sharpness. It is also small, light and stupidly cheap. I also have the Zeiss 21mm and it's pretty nice but I wouldn't take it to the grave - it isn't as good to the edges as I'd like and it has some field curvature.

I say: the Sigma is lovely but it does have two 'issues': firstly, its bokeh can be a bit too nervy if there are strong, repeated lines in the background. Secondly, I have had three copies and each has had mild but annoying decentering - and I suspect that this masks some field curvature, which might make it a tricky lens for landscape use. Mine all required at least +20 fine tune, too. I haven't tried the Nikon 24, the Zeiss or the Samyang but the Nikon 28mm is the second sharpest of the above group, very nearly as good as the Sigma, and though it can also be a bit tricky as a result of its field curvature it is capable of very sharp results indeed and I do use it successfully for landscape work. It has a nice 'look' wide open and is also very small and light. It is my choice - but then I prefer a 28 to a 35 in any event, and my 24-70 F2.8 Nikkor is pretty damned good at 35mm for when I do need it.

I say: I have none of these lenses - I shoot 50mm quite rarely and when I do, I prefer the amazing quality of my adapted 50mm F2 Leica R Summicron for critical use, or the flexibility and great quality of my 24-70mm F2.8 Nikkor zoom for travel use.

I say: the two Nikkors have the same scores, though the F1.4 version rates a little higher for sharpness. However, the F1.8 is a lot cheaper and it is still extremely sharp. I love this lens - and it focusses very reliably too. I also have the Zeiss and find it to be much sharper than the DXO score implies though not necessarily greatly better than the Nikkor F1.8G. The Zeiss has radical problems with LoCas even to F4 and sometimes F5.6 and if it didn't do great service as a macro lens, I would sell it. But my surprise verdict is that however good the Nikkor F1.8G is, the new 70-200 zoom is nearly as good and is a lens I always have with me when travelling. So for most use-cases, that's the one that gets shot.

Other Lenses to consider

DXO have covered a very wide variety of bases with this series of articles but there are two other things I'd like to see added in time. One is the performance of the new Zeiss F2 135mm Apo and the other is the vexed question of Perspective Control lenses. Nikon's lack of compelling wide T/S glass has proved a bit of a road block to some would-be D800 owners, who appreciate Canon's offerings in this area. My personal feeling is that the 24mm PCE (not yet DXOMarked) isn't up to the D800 and that I would ideally like the choice of a 17mm version, too. The upcoming Samyang 24mm alternative might offer a solution and I would love to see it covered by DXO.

Conclusion

So there we have it: DXO's lens scores are, for me, the perfect place to start when narrowing down a list of potential lenses  - especially given their attention to detail in testing lenses individually on specific camera bodies so as to get truly relevant measurements. But other factors often mean that, for individual photographers, real-world considerations must be used in addition. For that, I always use Photozone, Camerlabs and DigLloyd. Notwithstanding the above, I agree with nearly all their conclusions and where we differ, it is generally due to a particular and pragmatic requirement of my own. There is no other website that has compared so many lenses on the D800 and am personally very grateful to them for having done so.

Next week, being the Easter break, I will likely not be posting: but I am working hard with the Leica M240 and will be taking it on a trip to Eire in search of subject matter that will show it off to its best! Watch this space...