Nikkor AF 50mm f/1.8 D - Review / Test Report

Nikkor AF 50mm f/1.8 D - Review / Test Report Lens Reviews - Nikon / Nikkor (APS-C) Article Index Introduction Analysis Sample Images & Verdict Page 1 of 3 Introduction Welcome to the first Nikon Lens Test Report here in Photozone! Few lenses are sharper than those classic 50mm standard lenses at medium aperture settings so let's start with the Nikkor AF 50mm f/1.8 D, a lens which surely has its place in many photo bags out there thanks to its very low price tag and marginal weight. All upcoming tests will be performed using a Nikon D200, a 10MP APS-C DSLR with a 1.5x cropping factor. The field-of-view of the Nikkor is equivalent to 75mm on classic full frame SLRs so the standard lens is transformed to a moderate tele lens within this scope. The optical construction is made of 6 elements in 5 groups without any special elements. The minimum focus distance is 0.45m resulting in a max. object magnification of 1:6.6. The filter size is 52mm. As hinted above the lens is very compact (64x39mm) and light-weight (155g). The aperture mechanism feature 7 aperture blades. Despite its very low price tag the build quality of the lens is very decent. The outer barrel is made of polycarbonate combined with a metal mount. The rather small rubberized focus ring operates very smooth. As you can see above the lens extends a little bit towards closer focus distances. The front element does not rotate so using a polarizer is no problem. The lens has no internal AF motor and relies on a slotted drive screw operated by the camera. As a result AF operation will generate a moderate degree of noise. The AF speed is very decent on the D200.

Distortions

As expected for a fix-focal lens the level of (barrel) distortions is very low (0.26%) and nothing to worry about.

The chart above has a real-world size of about 120x80cm. Possibly things may get a little worse with extreme close-ups.

Vignetting

Thanks to the sweet spot behavior on the D200 vignetting is very well controlled. Wide-open vignetting is a little stronger at ~0.66EV which may be visible in very critical scenes. From f/2.8 and up the problem is negligible.

MTF (resolution)

Update 04/11/2006 - tested new sample which performed better at the borders.

Standard lenses are stellar performer when used at medium aperture settings and the Nikkor AF 50mm f/1.8 D is no exception here. At f/4-f/8 the lens is surely as good as it gets on the D200 with an excellent center and a very-good border performance. Nonetheless it is also fairly typical for ultra-large aperture lenses that things aren't quite as rosy at wide-open aperture but the center is already excellent here whereas the borders are a bit soft (combined with rather low contrast). From f/2.8 and up the distribution of the MTF50 curve suggests that the center performance exceeds the quality of the D200. The borders improve continuously with good figures at f/2.8 and very-good results at f/4.

The lens showed slight residual spherical aberrations (focus shift when stopping down).

Below is a simplified summary of the formal findings. The chart shows in line widths per picture height (LW/PH) which can be taken as a quantity for sharpness. The chart is limited to the visually relevant LW/PH range of [750, 2250]. If you want to know more about the MTF50 figures you may check out the corresponding Imatest Explanations.

Chromatic Aberrations (CAs)

Chromatic aberrations (color shadows at harsh contrast transitions) are relatively pronounced for a fix-focal with an average pixel width of 1.2px at the image borders. Nonetheless it´s not a major problem. Stopping down improves the issue to moderate figures.

Sample Shots

Ok, finally here're some sample shots taken with the Nikon D200 (converted RAWs via RawShooter Essentials 2006).

Click on a thumbnail to view the original file (opens in a separate window). Please note that the originals are FULL SIZE samples (=several megabytes) thus requiring a significant amount of bandwidth so please take care of the limited resources here.

Make NIKON CORPORATION Model NIKON D200 ISO Speed 200 Focal Length 50.0mm Exposure Data: f/1.8 @ 1/3200s Size 2613x3898 Make NIKON CORPORATION Model NIKON D200 ISO Speed 200 Focal Length 50.0mm Exposure Data: f/4.0 @ 1/160s Size 3898x2613 Make NIKON CORPORATION Model NIKON D200 ISO Speed 200 Focal Length 50.0mm Exposure Data: f/8.0 @ 1/160s Size 2613x3898 Make NIKON CORPORATION Model NIKON D200 ISO Speed 800 Focal Length 50.0mm Exposure Data: f/3.5 @ 1/1500s Size 2613x3898

Verdict

The Nikkor AF 50mm f/1.8 D is a low profile lens with less sex-appeal than the big glass but it is an interesting lens nonetheless. At wide-open aperture it is a little soft at the image borders and the contrast level is a little on the low side. However, at medium aperture settings the resolution figures are exceptionally high and surely a benchmark to beat. Distortions are negligible and vignetting is very well controlled. The build quality of the lens is very decent and the AF performance leaves nothing to be desired.

Optical Quality:     Mechanical Quality: Price/Performance: