This is not a definitive review of the lens since I only got it a few weeks ago. These are my brief initial impressions. A full review should follow as I gain more experience with the lens.
The lens is light. It is in fact incredibly light for a fixed lens with a long reach. It is easy to handhold for a few hours without too much strain. The lens is also amazingly short for such a long focal length. It is hard to get over the fact that I am getting 500mm out of such a compact lens. Although it is small and light it does not feel like a toy. Substantial but light and compact is how I would describe it in a few words.
Initial image quality impressions were good but not great. I suspected the lens had focusing issues and a LensAlign test confirmed this. Fortunately the lens needed only a minor adjustment. I used the fine tune adjustment on my camera bodies and after dialing -5 on one of my camera bodies and -7 on the other, it seems to focus right where it should and sharpness has been restored. Colors and contrast seem to be excellent.
So far there are only two minor negative points I can bring up:
The lens collar is non removable. The lens foot can be removed but not the collar itself. Since I will mostly use this lens hand held, there is no reason why I should want the collar there permanently. It's not a big concern but the bottom of the collar itself digs into my hand when I am using the lens and It is uncomfortable. I can deal with it. Regarding the lens foot, there are many articles on the web that state that it should be replaced by a better quality foot from Kirk, RRS, Hejnar or Wimberley. Many people have reported that the Nikon foot can suddenly disconnect from the collar when holding the lens from the foot for transport. Not good ! Of note: The RRS and Kirk foot replacement can be used and removed as desired just like the original Nikon foot. The Hejnar and Wimberley options are "almost" permanent as they are fixed with a screw that makes them extremely reliable but more of a hassle if you want to take them off and put them back on repeatedly.
The lens hood is a cheap plastic one of the same type that Nikon uses for many of its less expensive lenses. At this price I was expecting carbon fiber. I guess they had to cut costs somewhere. It works as it should but its inferior material contrasts with the overall quality of the lens.
These are my impressions so far. More to be added later.
* After a few months of use, my initial impressions still hold true. I can add a few points.
After using a few faster long lenses in the past (200-400mm f/4, 70-200mm f/2.8 and 300mm f/2.8), the loss of one or two stops of light is quite evident in some situations. In overcast outdoor situations with an f/2.8 lens, I was very rarely concerned with my ISO settings. If I needed more light to shoot at a low ISO setting I would simply open up the lens. At f/5.6, ISO settings vs shutter speed have to be closely monitored or blurry shots will ensue. This is especially evident when shooting fast moving birds. I don't like shooting at higher ISO settings but with this lens it is sometimes necessary to push the ISO at 800 or above. It is the price to pay to get a high optical quality 500mm lens of such small size and weight. Not a deal breaker for me but definitely something to think about. Some will prefer the faster, more expensive 500mm or 600mm f/4 for this reason alone.
The lens will not isolate a subject as well as a 500mm f/4 lens would if both lenses are shot wide open especially if the subject is close to a densely populated background. Nothing new here. Still, so far I am quite satisfied with the background rendition wide open.
Even though shooting at f/5.6 can have its limitations, Nikon has made sure that this lens is sharp wide open. There is absolutely no need to stop it down for added sharpness. Brad Hill (naturalart.ca) has extensively tested this lens at different aperture settings and his tests confirm this. There is no gain is sharpness at f/8. That is quite remarkable in itself. Every single image I have shot with this lens has been wide open.
Those of you who have read about phase Fresnel lenses know that they can have negative optical issues in certain situations. This has happened to me when shooting through glass towards a light source (even indirect). I have seen some reviews where photographers have used high quality protective or UV filters on the lens with negative results. I have not tried this myself as I don't use these filters anymore but It is something I wanted to bring forward. Apart from shooting through glass or with a filter, I have not noticed the possible negative effects of using a lens with a phase Fresnel element.
Is this lens a game changer ? After a year with it I can honestly say that for me it is. I'm still in awe at how close I can get to my subjects with such a small and light lens. It's a modern tech wonder from Nikon. The older I get, the more I care about the total weight of the gear I am carrying and this lens is truly a joy to use as I never feel weighed down or uncomfortable while using it for extended periods of time. Hand holding is never an issue.
As much as I like the lens, I'm hoping Nikon will finally come out with a 600mm f/5.6 of the same type. The patents for the lens have been deposited by Nikon years ago and a detailed plan of the lens can be readily found online. There has been rumors of the lens being announced by Nikon for years. Still nothing and the rumors seem to be dying out. The reason I mention this is that the more I go out to photograph birds, the more I long for more reach. On a crop sensor (750mm equivalent) I find reach is often sufficient to have a frame filling subject (or close to frame filling). On a full frame camera, I find I crop most of my images a lot more than I would like to make the subject stand out. I can now better understand why some wildlife photographers will not even touch a 500mm lens. They will only use a 600mm or 800mm lens. For small skittish creatures in the wild, reach is everything. It does come at a price though.
American Goldfinch
Photo above taken with the D500 and 500mm PF at 1/200 F/5.6 ISO 400
warblerPhoto by Michel Fleury
Photo above taken with the D500 and 500mm PF at 1/800 F/5.6 ISO 400