Summary:
Pros:
- 180×180 degree field of view.
- Smart design, smooth operation.
- Reasonably sharp.
- Opportunity to create immersive panoramas.
Cons:
- Wasted sensor space means a low resolution image.
- Not good for high-res landscapes.
- Pricey.
Detail:
The fisheye has a reputation of being a novelty/niche lens (and I won’t argue that it isn’t), but I found myself getting a lot of use out of it, especially for landscapes. I will say that I’ve never been a big fan of the distortion that is typical of a fisheye and usually correct it in post.
Recently, I sold my Nikon D80 and upgraded to the full-frame Nikon D700 and I sold all of my DX lenses along with it. This included my Nikkor 10.5mm Fisheye and it didn’t take long for me to miss it. The Nikkor 24-70mm 2.8 along with the d700 is pure magic, but to me, 24mm is just not a wide enough for a satisfying landscape so the hunt was on for a replacement.
It was about that same time that I heard a comment from one of the folks on TWIP talking about how much he loved his Sigma 8mm Fisheye. I’m pretty hardheaded when it comes to the brand of lens I use. Everything else in my bag is pure Nikon so the idea of tossing a Sigma in there wasn’t a decision I took lightly. However, I couldn’t ignore the praise being dished out from TWIP so I looked around and read up on it. The comments I saw were mostly positive, but at around $800 with shipping, plus the fact that it wasn’t a Nikon, I decided not to buy. It was apparently in the cards for me to have that lens, however. A short time later I was browsing ebay and saw a Sigma 8mm Fisheye being sold from Canada and advertised as mint condition/new. With the combination of the global economic implosion causing people to sell their possessions, the exchange rate in my favor, and no one else bidding, I ended up getting the lens for less than $400.
When the lens arrived I was immediately impressed with the 180 x 180 degree view, though it took some conscious effort to keep from having fingers/feet/elbows in the shot. I also thought that the slip-off ring/cap was a great feature as it offers both protection for the glass and the ability to add a front filter if desired, though having the ring on will reduce your field of view. It also accepts gel filters in the back if you prefer not to lose the FOV.
One of the oddities that I had read about, but not yet seen, comes from this lens producing a circular image on the sensor. I’ve found this to be positive and negative. The physics of it makes sense. If you’re going to have a 180×180 view and you don’t want crazier distortion than you’re already getting, you’re going to have a circle. The problem with laying a circle down on top of a rectangular sensor is that you’re wasting a whole lot of horizontal sensor which means a smaller image (once you crop out the black) and effectively less resolution in your image. This is not a good thing when you’re shooting a landscape. There is also an additional ring around the image which is a bit odd (and can be cropped out of course.)
The best use for this lens that I’ve found has to be its ability to make immersive panoramas with very few shots. (If you’re not familiar with those, it’s the thing you’ve probably seen on a realty website where you can take a virtual tour of a room like you’re standing in the center and looking around inside a sphere.) With the actual 180+ FOV, you can technically do a complete sphere with just two shots (however, I have found that three or four work a little better.)
In Conclusion:
Knowing what I know now, the Sigma 8mm Circular Fisheye lens is not something that I would recommend if you’re looking for a new landscape lens or if you’re stuck paying retail price. However, if you spot a deal on one and want to get into the world of 360 Panoramas and equirectangular images, or you just enjoy the goofy distortion effects of a fisheye, definitely give it a look.
To see many more photos from many more photographers using this lens, check out the Sigma 8mm Fisheye group on Flickr at:
http://flickr.com/groups/75097097@N00/pool/