This review will emphasize the lens MTF50 resolution performance and how well the lens auto-focuses.
I was feeling guilty about not writing a review of what is probably the most populous Nikon lens of the modern age. So here it is.
The lens is so light that it feels like it’s filled with helium. It’s supplied with a lens cap and an end cap and … nothing.
The lens has a plastic lens mount and no rubber seal. Exactly as you’d expect.
So what DOES this lens have? It has resolution. And it’s my go-to lens for infrared. Large, quality infrared filters are devilishly expensive, so the 52mm filter threads on this lens are a welcome sight.
This lens won’t let you override auto-focus with the focus ring, which I used to think was a ‘given’ with AF-S. Wrong. You have to switch the lens to “manual” focus.
Major complaint here. The auto-focus fine-tune on this lens is ZERO at 55mm, but it’s -4 at 18mm (these numbers are for my D7100, but different on the D7000). Since this isn’t a Sigma lens with the ability to fine-tune at various focal lengths and distances, I’m kind of stuck unless I stop the lens down to f/8 or so. I decided to split the difference and set the fine-tune on -2.
The skinny plastic focus ring is right behind the 52mm filter. There is no focus scale. Given this meager working set, it can be tricky to manage getting the lens focused, keep the focus ring steady, and screw on an infrared filter.
The auto-focus DOESN’T have any chatter using my usual AF-C and rear focus button. Yay!
Speaking of auto-focus, this lens is more in the ‘turtle’ category than the ‘rabbit’ category. At least it eventually gets there. I exaggerate, of course.
Nikkor 18-55mm and its included hood. Using my classic (1974!) L39 filter.
Get a load of that world-record-skinny focus ring knurling behind the filter! Speaking of the filter, it’s not one you’d want to point toward the sun. It’s uncoated, but it has been my friend most of my life and I could never get rid of it.
Vibration Reduction (VR)
This version of the lens has VR; the original version didn’t. Newer versions now have “VRII”. I was able to get about 2.5 stops of anti-shake, but my results vary a lot. Everybody is different in how they support the camera while hand-holding it, so any quote about VR effectiveness isn’t really a rule; it’s more of a guideline. Yes, that line was stolen from Jack Sparrow.
This review is looking at a single copy of the lens. Yours will be different, but hopefully ‘similar’. Some day I might get around to testing more of these things, since I have a few more laying around.
These tests were done using a Nikon D7100 (24 MP) with unsharpened 14-bit compressed RAW format.
Resolution is a 2-dimensional thing. The tests that follow show you how resolution varies throughout the frame. The resolution charts are split into “sagittal” direction (like wheel spokes) and “meridional” directions. These directions match the MTF references published by Nikon. What’s different, though, is the following values were MEASURED versus Nikon’s “theoretical” values.
Also, the sagittal direction is quite good. The meridional direction isn’t nearly as good and is the culprit in dragging down the MTF50 numbers.
I use a (free!) program called MTF Mapper from here to measure lens resolution. The download site also includes files for printing out the resolution targets (mine are A0 size on heavy glossy paper, dry-mounted onto a board). This program is covered in more detail in my MTF Mapper Cliff’s Notes article. The software is comparable to ‘Imatest’ in the quality of the MTF measurements, and it uses the “slanted edge” technology similar to ‘Imatest’, also. The author of MTF Mapper, Frans van den Bergh, provides this excellent software for FREE. Visit his site and give him the praise he so richly deserves.
The chart design used for resolution tests orients all of the little black squares to be ‘slanted’ but they’re generally aligned in meridional and sagittal (think spokes on a wheel) directions to correlate better with the usual MTF plots you’re familiar with. There’s often a dramatic difference in sharpness between these two directions, except in the most expensive of optics.
If you spot some small islands of resolution peaks/dips in the following charts, you can safely ignore them. Visually imperceptible variations in the surface of the resolution chart can show up rather dramatically in the plots, because the analysis software is exquisitely sensitive.
What the resolution target looks like. Mine is mounted ‘upside down’.
At long last, I’m getting around to some actual resolution results.
Tests were done with “Live View” AF-S auto-focus, contrast detect, IR remote (via a cell phone), VR OFF, and a really big tripod. I use the “best of 10 shots”; not every shot gets the same resolution results. All cameras operate on the “close enough” principle for focus, so many tests are needed to determine the best resolution that the lens can produce.
Corner at 18mm f/3.5
Center at 18mm f/3.5
While definitely not a ‘pro’ lens, this lens is still capable of producing some fine photographs, even wide open. You can’t beat the price.
Without a distance scale, even manual focus can be a challenge.
With my copy, the longer focal lengths are the weakest (typical of almost all zooms, by the way). Corners aren’t stellar, but surprisingly good. The center is really good at all focal lengths; nothing to complain about here.
My own style dictates that I use this lens at 18mm maybe 90% of the time. Luckily, it has great optical performance at that length.
18mm f/10 Hoya R72 (Infrared) with Red/Blue color channel swap
Sequoia 18mm HDR using Efex Pro2 HDR. Some chromatic aberrations visible