[This post was updated on Nov 16, 2015: in my first post I used image size reduction in Photoshop which did not help in viewing the actual differences between the images of the two lenses. The images are now reduced in size by using JPG compression instead without any visible loss in quality. This should hopefully reflect the differences between the lenses better!]
Ever since I decided to spend a ridiculous amount of money on the amazing Nikon AF-S 600mm f/4 E FL (Fluorite) super telephoto (the ‘new’) lens, I hoped that it performs better than its predecessor, the Nikon AF-S 600mm f/4 G (the ‘old’ lens). It’s a bit like you hope your new iPhone/Android performs better than your previous model, your new car runs faster than your old one, your new DSLR has better ISO performance than the one you bought just a few years ago … etc.
After some email communication with a professional – and well known – nature and wildlife photographer from Canada who I’ve had the pleasure visiting a couple of years ago, I was interested even more in any differences as he was/is quite confident both models would be similar in optical performance. He shoots (mostly) with the new Nikon AF-S 400mm f/4 E FL but still owns the ‘old’ AF-S 600mm f/4 E G lens as well and is not looking at replacing for the reason mentioned.
So in other words, I may have spent thousands extra on a lens with similar quality as its predecessor. And if that’s truly the case, that would, let’s say, suck quite a bit… Right, as we say in The Netherlands: ‘meten is weten!’ which translates to something like ‘to measure is to know!’ (rimes better in Dutch… :) ).
I had the opportunity to hire the ‘old’ Nikon AF-S 600mm f/4 G at my local camera retailer and I started checking out the differences – and similarities. Both models are actually sold currently, although the new model is only available in (very) small quantities. While I don’t have the facts, I can image Nikon is ramping down development of the old model to give way for the new one, albeit that the price difference is significant (app. 4K EUR/$) and customers may still opt for the old model.
Before I go to the comparisons, the first thing that struck me was that the hoods can actually be interchanged! Much has been said about the (too) large size of the 2-part hood of the ‘old’ AF-S 600mm f/4 G lens; well the new one has about the same hight and diameter. And the old hood fits perfectly on the new lens and vice versa!
My understanding of Nikon’s new Fluorite lenses is, and has been that they are already very sharp at maximum aperture (e.g. ‘wide open’) and exhibit that sharpness in a more lineair pattern, unlike the previous generation that reaches maximum sharpness somewhere between f/5.6 and f/8.
I used the same object as in my previous tests (little transformer box at app. 100 meters/yards) and mounted the new and old 600mm lenses to my Nikon D750. I wanted to get as much resolution as possible out of the images – that’s why the D750 and not my D4S (I don’t have the D810 – as I wrote about a couple of blogs ago…). The whole set was mounted on a Gitzo tripod and Wimberley gimbal head; the D750 was set with a 3 second shutter delay mode to prevent camera/shutter shake as much as possible. I took shots ranging from f/4 to f/8 and with speeds of 1/250 and 1/500 sec. and VR was set to off. By now I’m sure you’ve figured out I’m not using any quantitative, semi-scientific measurements like Imatest or similar. Instead, I look at the results on my Dell 4K resolution monitor with Nikon ViewNX2 displaying the images at 100% and converting the RAW files at the highest JPG quality settings. What this means is that I will not be able to specify with 10 decimals which lens outperforms the other in terms of sharpness, vignetting, bokeh, etc. but it does mean that I get a pretty good idea, qualitatively based on my own observation. So… let’s get started!
Surprisingly, there are surprises :)! First thing I noticed: the rather significant difference in sharpness. The images with the 600mm G lens were all soft (or soft + blurry) whereas only a few with the 600mm E lens were ‘blurry’; i.e. due to camera/lens shake. Also the color rendering of the new lens is different compared to the previous one. My white balance was exactly the same as I only changed the lenses; my camera stayed the same between shots. I guess, different glass, different colors! Based on the number of shots I took and the varying sharpness in the shots, I came to the following conclusions:
At 1/500 sec. and wide open, the AF-S 600mm f/4 G is a fraction better than at 1/250 sec. (which is in line with my ‘shake by diaphragm’ – theory) but still visibly softer than the AF-S 600mm f/4 E. Let’s move on to f/5.6!
At f/5.6 the and 1/250 sec. the AF-S 600mm f/4 G catches up. The new lens still, in comparison, has the edge in terms of contract and sharpness (see next images on that as well).
At f/5.6 and 1/500 sec.: same story. The differences between the old lens and the new one are a bit more visible; i.e. better sharpness and contract for the new Nikon AF-S 600mm f/4 E.
OK, the basic comparisons are done and it’s clear (at least for me) who the winner is. Let’s try and get some more ‘evidence’! How about comparing each lens at different apertures:
Just as I expected – there is quite a difference in sharpness when you shoot the Nikon AF-S 600mm f/4 G ‘old’ lens at f/4 or f/5.6. And this is in line with pretty much all literature and other measurements/experiences from photographers related to these types of Nikon lenses. How about the difference with the new Nikon AF-S 600mm f/4 E?
If I really had to choose, I’d go for the one shot at f/5.6, but the differences are very, very small. Again, this is in line with the current literature and findings/reports/blogs/etc. from around the world: the new Nikon Fluorite lenses are much sharper across their aperture range; i.e. the curve is more lineair compared to the previous generation of lenses.
My last comparison is between my sharpest shot with the G, and with the E lens, so regardless of aperture and shutter speed: the Best vs. the Best!
The image on the left from the ‘old’ G lens looks pretty good! However it’s still not on par with the image on the right from the ‘new’ E lens in terms of sharpness and contrast. The settings? The Nikon AF-S 600mm f/4 G was shot at f/8; the Nikon AF-S 600mm f/4 E was shot at f/4, both 1/250 sec.
Conclusion of conclusions:
For those photographers out there who (still) truly believe these lenses are optically the same (to a large extent), please feel free to run your own test and publish your results!
For any questions or feedback, just drop me a note at: firstname.lastname@example.org
Life/Nature, November 15, 2015