Having made the switch from the Nikon DX format to the Nikon FX (full frame) format I’ve had to completely renew my arsenal of lenses. This hasn’t been as tough as I thought with many of my DX lenses selling for about the same price as purchasing used FX lenses. I did purchased a number of new lenses, that’s another expensive story completely!
One of the hardest decisions I made was to sell my Nikon 10.5mm fisheye. This is a truly incredible lens when it’s required and I was always amazed at the sharpness, even wide open. I didn’t use it a lot but it produced many memorable images that have been published and raved about. Can’t beat that!
One factor I looked at is that on the Nikon D800, my current camera, using this lens would still produce a 15.3mp image, larger than my previous cameras of 12.3 and 12.4mp. No problem really, I have published books and posters with cameras with fewer megapixels than this and in most cases 15+mp is all you would need, even for a coffee table book double page spread! This is why it was a tough decision. To sell or not to sell?
Having read reviews about full frame fisheyes, I decided the Sigma 15mm f2.8 was a likely candidate for a replacement while the Nikon 16mm f2.8 was not. This is not purely because of cost but because my experience has been that older non digital era Nikon lenses (and most others I expect) just aren’t as sharp with the modern digital cameras. For instance, my new Nikon 24-70mm f2.8 zoom is sharper than my old 85mm fixed focal length lens that I have used for the past 25 years. Wasn’t expecting that!!!
I checked my usual “used” sources for lenses. Shopping around I found a very clean used example of the Sigma 15mm f/2.8 EX DG Diagonal Fisheye (what a mouthful that is!) for $400 shipped and without thinking too much made the purchase. Selling my like new Nikon 10.5mm fisheye wasn’t as easy as I would have thought because I “didn’t have the box”. I guess this is important to the folks that buy and sell routinely but that’s a rant I won’t get into at this time. Anyway, Nikon sold for $360, new used Sigma for $400, can’t complain too much about that.
How does it perform? Well, it’s a little of a mixed bag here. I’m not convinced the Sigma is quite as sharp in the corners as the Nikon but we do have to remember that we are comparing my new Nikon D800 at 36.4mp with my old Nikon D300 at 12.3mp. It would have been great to have both lenses to compare at the same time but the reality is I’m not an equipment junkie and when I make the decision to switch systems the old stuff goes. If I resize the images to match, the Nikon is OK all the way to the corners while the sigma falls off at the very edges of the corner. It’s really very close and one thing I noticed on the images that I have viewed is that the chromatic aberration on the Sigma is not as pronounced. Overall they both are sharp lenses and could easily produce 16×24 inch prints of very high quality. This is what really matters, both these lenses perform well and produce the quality that even a professional photographer requires. My verdict… I have to give the edge to the Sigma from what I have seen so far. It seems a little sharper overall and sure is a good deal at the price.