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© 2004 KenRockwell.com Lens Test Glossary About these reviews
NEW: How to Use Ultrawide Lenses 11 August 2008 Introduction I was hoping this lens might be a significant step forward in lens performance. I had had such good luck with what appeared to be a lens of similar pedigree, the fantastic 28mm f/1.4D AF, that I was sure the 18mm AF must have to be better than the common 20mm f/2.8 AF designed back in the 1980s. Both the 28/1.4 and 18/2.8 came out around the same time, use an aspherical element (the 28mm has a precision ground element, the 18mm merely a molded one) and seem built to the same high mechanical standard. Unfortunately the $1,000+ 18mm f/2.8D AF it is no better overall than the $400 20mm f/2.8 AF optically. Oh well. The 18mm does feel like you've bought a premium product, however. Specifications It has thirteen elements in ten groups. It has a molded glass aspherical element. It focusses as close as 0.25m or 10 inches. Oddly, even though it's rear focussing Nikon doesn't list it as having close-range correction. The 18mm f/2.8D AF takes standard 77mm filters. It has a seven-bladed diaphragm stopping down to f/22. It comes in a nice case with an HB-8 hood and is much sturdier then most AF lenses, especially the 20/2.8. It has the same styling as the 28mm F/1.4D AF, 20-35mm f/2.8D AF and 85mm f/1.4D AF, which means a nice metal filter thread and the only plastic to notice is the AF window and the aperture ring. Nikon Product Number: 1911. Performance Performance is certainly usable, but unfortunately almost identical to my old 20mm f/2.8 AF. AF speed is very fast. One full turn of the AF screw focusses the lens from infinity to 1.5.' Whew, that's fast! It is a bit sharper than the 20/2.8 AF wide open, but never gets never perfectly sharp in the corners at any aperture. It has lots of little ghosts; worse than the 20/2.8 AF. You need to use the obnoxious hood included, unlike with the 20mm AF whose hood you don't need. It has the typical barrel distortion, and despite all the hoopla about having an aspherical element to eliminate distortion, has the same complex distortion signature as the 20/2.8 AF. Color balance was a point or two cooler than the 20/2.8, probably not enough to ever notice. Recommendations I suggest passing on this lens. There are two better choices. 1.) If you want the same performance for less money, get a 20mm f/2.8 AF instead. The 20/2.8 has better ghost performance and the same sharpness and distortion performance as the far more expensive 18/2.8D AF. 2.) If you want to spend a little more money and get better performance, get the 17-35mm f/2.8D AF-S. I have not directly compared them, however the 17-35mm is better than my 20AF, and therefore is probably much better than the 18mm at its own game. The 17-35mm set to 18mm probably does have more distortion than the 18mm itself, however the 17-35mm has much better sharpness, fewer ghosts and less falloff than the 20mm, and therefore the 18mm as well. The only reason to get the 18/2.8 AF is if you have a large insurance replacement claim that you need to use or loose, and don't mind the additional ghosts compared to the 20mm. OK, it is more solidly built and does take my preferred 77mm filters. I don't recall checking to see if I could stack more than one 77mm filter on the 18mm without vignetting, as I can with s 62mm->77mm step-up ring on my 20mm. |
