Wednesday, September 16, 2009
Spiratone 18mm Vs. Nikon AF-S 17-35mm Comparison
**I have performed a more recent and thorough comparison including the Tokina 17mm f/3.5 AT-X Pro.**
So I finally got around to it! Today was beautiful so I decided to go out in the back yard and put in some time with science.
To set things up: I wanted to just see a side-by-side of this Spiratone lens with something much nicer...you know, just to see! Quite frankly, no big surprise here, a lens that was originally just about $200 vs. a lens that still sells for $1000 despite having been designed more than 10 years ago. Which did ya think was going to come out optically superior? Yerp...
Nevertheless, this little spiratone has one major advantage in my mind, over the 17-35mm. Size. Something about having a 17mm's worth field of view that doesn't weigh down the neck, nor turn the heads of curious passerby's is very exciting. I suppose I could crack and drop a couple hundred more for something like Tokina's AF 17mm AT-X Pro or go more extreme (which is only a matter of time right now...) and pick up a Tamron or Sigma made 14mm rectilinear.
On top of all that, for some instances, I really like the vignetting and tone this lens interprets. And, I like the solid metal feel, rather than new plastic garbage. Ok, so perhaps I simple like the way it looks, no big surpise there!
Let's get to it! The first image is just to show the overall images as a whole at each aperture side by side. Images were shot on a Nikon D700 @ ISO 200. I had to shoot them as .jpg so there is some manipulation (just whatever takes place in-camera) but it is equal across the whole set, so methodically speaking, no big deal.
First off, it seems the Spiratone has a slightly wider field of view as well as a bit different distortion than the Nikon. This can be seen in the bottom left where the field of view pulled in the railing of my deck just a bit whereas the Nikon did not. Go ahead and click on the images to get a better look.
Next, I took a three crops from each lens' image at each aperture.
Also here is a hastily-made sample of the light fall-off of the Spiratone.
As I stated earlier, the optical design of the Spiratone appears to give it a wider field of view than the Nikon 17-35mm so in the comparison there is a tad bit of the deck railing entering the frame on the 18mm unlike the other lens. All told including my experience with the Spiratone in other conditions it seems it: produces considerably softer images both at the center wide open as well as near the corners throughout the aperture range, has a lot less contrast, is prone to flare as well as ghosting when aimed very near or at a bright light source, demonstrates an increased amount of chromatic abberation around the edges of the frame, shows light fall-off severely at f/3.5 and subtly from there until about f/8, and definitely has some distortion issues. Wait, isn't that just about EVERY optical aberration? Yep. So why bother with this lens?
Again, I didn't expect this test to shock anyone. I wasn't attempting to reveal a sleeper lens (although if I did, that'd be pretty cool). Just curiosity. That being said, this lens isn't useless.
Obviously the Nikon AF-S dominates the Spiratone technically speaking, that much should be, given the vast price difference. But from this, you can see how much different. Is it enough to make that difference? Does the Spiratone perhaps meet your personal needs just fine? Are you shooting for something that necessitates corner to corner sharpness and little other aberrations? Or are you just walking around capturing, creating moments and can lend yourself to a more varied optical interpretation? If nothing else, the Spiratone provides a valuable introduction to shooting wide angle (especially on an FX sensor) for a relatively low price. I took a photo a couple posts back, the two chairs on the deck, with the Spiratone and I truly love the way it turned out!
There is no right or wrong with these lenses (unless you have specified requirements within a particular assignment). I say, if you see one of these little gems around in good condition (for $100 or less prob), and you have never shot a wide angle before pick it up! They tend to run about $100 depending on mount and condition so if it turns out its not for you, you will most likely be able to get what you paid for it back. They're especially fun on full-frame cameras!