Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF

Introduction

Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF was first released in early 2000 to compliment the growing range of Nikon's arsenal of standard zoom lenses. Nikon followed up with an updated version of this lens circa 2003, however, Nikon AF-S Zoom Nikkor 24-85mm f/3.5-4.5G IF ED was very short-lived - by 2008 Nikon discontinued the new variant, leaving the older AF-D version still in production. The lens lens sells for ~US$550 (as of January 2009), which obviously makes it quite affordable for mainstream users.

The build quality of the lens is OK - the barrel and lens cams are plastic, the zoom and focusing rings are rubberized and are pretty smooth to operate. The aperture ring is plastic as well and clicks in into positions with a snap, although the ring itself is located right at the base of the mount and is somewhat hard to grasp comfortably when the lens is attached to a camera. The inner cams wobble a little bit, especially when the lens is fully extended. The lens is surprisingly compact when fully collapsed - it measures only 78 x 82mm (3.1 x 3.2in), but once the lens is zoomed towards the long end of the zoom, its length almost doubles. Weight-wise, it's average for standard zooms - at 545g (19.2oz) it is not going to break your neck.

The optical construction of the lens consists of 15 elements in 11 groups and sports an internal focusing design, so that the lens cams do not extend during focusing. The focusing mechanism is fully mechanical - the lens does not have a dedicated focusing motor, so the lens elements are moved in and out of focus using camera's drive pin that locks into a slot on the base of the lens mount. Nikon chose this design to ensure the backward compatibility of its first generation AF lenses with older cameras. Manual focusing is still possible with a dedicated focusing ring, however, the focusing system is a little bit unusual on this lens and deserves a few additional words. The minimum focusing of the lens is 50cm (1.6ft) in the full zoom range, however, in the 35 to 85mm range, the lens is capable of focusing closer then 50cm - all the way down to 21cm to be precise. This range is marked with as a macro range on the lens. The switching from normal to macro range is a little bit tricky - you actually have to zoom the lens to at least 35mm before being able to engage the focusing in the macro range. And once in the macro range, the lens will prevent you from zooming closer then 35mm. The lens has a Normal/Macro switch on the side of the body, which can act as a limiter to the auto focusing system. At its closest focusing macro distance at 85mm, the lens gives its maximum magnification ratio of 1:2 (impressive for a zoom, but it's doubtful the lens will replace a dedicated macro).

The lens supports both manual as well as in-camera aperture control. The dedicated aperture ring rotates from f/2.8 through f/22 in one full f-stop increments. To enable an in-camera electronic aperture control, you need to turn the aperture ring all the way to f/22, which is marked in different color, and then flip a tiny switch located right above the ring. This will lock the ring into the position and enable the mechanical coupling between the aperture ring and the camera.

Image

The factory box includes Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF lens, front and rear lens caps, HB-25 lens hood, registration and warranty cards. Like all AF-D lenses, AF Zoom Nikkor 24-85mm f/2.8D IF is a full frame lens, so when used on an APS-C type cameras with 1.6x crop factor, the field of view of the lens will resemble that of a 38-136mm zoom. Since the lens has a dedicated aperture ring, it would be relatively easy to adapt it to a number of alternative mounts, including Canon EF/EF-S cameras and Olympus' Four Thirds.

 

Summary
Lens Composition 15 elements in 11 groups
Angular Field ~28-84 degrees
Minimum Focus 0.5m/1.6ft
Focusing Action AF/MF
f-stop Scale f/2.8-f/22, camera/manual
Filter Size 72mm
Lens Hood HB-25 (included)
Weight 545g/19.2oz
Dimensions 78.5x82.5mm/3.1x3.2"
Lens Case CL-S2 (included)

 

Field Tests

On paper, Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF looks like a dream multi-purpose lens, you know the lens you'd pick up if you could carry only one lens with you. It is compact and light, it is wide enough to give you decent coverage on the wide side and long enough to work as a portrait lens and a close-range telephoto (close range telephoto - is this an oxymoron?). What else would you need? Ah, optical performance and good handling... Well, everything in due order.

The auto-focusing performance of Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF is quite good, thanks to a very short focusing path - rotate the focusing ring for ~45 degrees to go from infinity to the closest focusing distance of 50cm, and another ~45 degrees to cover the entire span of the macro range. As you can imagine, precise manual focusing with such short rotation of the ring is practically impossible. The lens does not even have a DOF scale, but even if one was included, it would have been pretty useless on this lens because of such short drive.

One thing to keep in mind when using this lens at wider focal lengths is that if you rely on an in-camera flash, you will likely to see some light fall-off at the bottom of the image frame. While the lens is pretty compact, the tip of the lens will still be caught in the light path. And if you are using a lens hood, expect to see an even more pronounced shade from the fall-off.

Image performance-wise, the lens produced somewhat mixed results in the field. Image quality changed across the zoom range, with better results at wider end of the range. Images remained sharp in the center, no matter what focal length, but border quality did vary from pretty good at 24mm to 'softish' at 85mm, with more or less decent results in between.

 

ISO 400, 1/30, f/2.8, 24mm (Nikon D3)
ISO 400, 1/30, f/2.8, 24mm (Nikon D3)
ISO 400, 1/13, f/4, 85mm (Nikon D3)
ISO 400, 1/13, f/4, 85mm (Nikon D3)

 

One of the more interesting features of this lens to test was the macro capability. AF Zoom Nikkor 24-85mm f/2.8-4D IF is one of few zooms that produce a 1:2 magnification. As mentioned in the intro section, macro range is only available in the 35mm to 85mm range and you need to first preset the lens into this focal range before switching it into the macro mode (which unlocks the macro focusing range). Anyhow, all this fiddling aside, image quality at macro distances was somewhat off when compared to images taken at infinity - slightly softer, slightly less contrasty, even somewhat desaturated. And regretfully, these characteristic carried through to close distance photography in general - the lens seemed to behave much better (in terms of image quality) at infinity then at close ranges. For example, when shot at wider apertures at 24mm and close distances, the lens produced rather ugly OOF areas - harsh and unpleasant highlights, poor contrast transitions, even occasional double-edging around fore/back-ground out of focus objects. Not much improvement at longer focal lengths either - same 'busy', distracting feel about OOF highlights and mediocre, non-contrasty transitions in the background and foreground.

 

ISO 400, 1/25, f/3.2, 35mm - macro (Nikon D3)
ISO 400, 1/25, f/3.2, 35mm - macro (Nikon D3)

 

Flare handling was rather poor. As can bee seen from the two shots below, with a strong direct light source positioned close to the picture frame (~55 degrees on the left hand side of the frame), the lens produced very noticeable ghosting both at wide as well as at small apertures (notice the rainbow patches as well as circular patches across the frame). On top of that you can notice a slight reduction in contrast at wider apertures, which is quite typical for many lenses and therefore is not a major surprise here.

 

ISO 200, 1/2000, f/2.8, 24mm (Nikon D3)
ISO 200, 1/2000, f/2.8, 24mm (Nikon D3)
ISO 200, 1/320, f/8, 24mm (Nikon D3)
ISO 200, 1/320, f/8, 24mm (Nikon D3)

 

As can be expected from a lens covering a span from moderately wide to medium telephoto focal lengths, vignetting was quite mixed. At wider focal lengths (24mm to 35mm), the lens showed moderate amount of vignetting on a full frame camera with wide open apertures. As you move towards longer focal lengths, vignetting is reduced, which can partly be attributed to slower maximum apertures in the 50-85mm range. APS-C camera handled vignetting much better, thanks to the smaller sensor size that does not cover the imaging circle of the lens - at 24mm the lens shows very minor vignetting at f/2.8, which practically disappears by f/4. And at longer focal lengths the lens shows very negligible amount of vignetting even at wider apertures.

 

Vignetting @ f/2.8 - full frame vs APS-C (24mm)
Vignetting @ f/2.8 - full frame vs APS-C (24mm)

 

Vignetting @ f/2.8 - full frame vs APS-C (85mm)
Vignetting @ f/2.8 - full frame vs APS-C (85mm)

The lens showed pretty noticeable barrel distortion at 24mm, which can be seen in the image samples below. Take a look for example at the picture of the Borders store, taken at f/8 and notice how much the palm trees as well as lamp pole in the left corner of the image are skewed. This heavy distortion obviously affects image quality to some degree, and also can be observed in many shots. Color handling (outside of the macro/closeup distances) was quite good in general - images carried good amount of contrast throughout the zoom range and color palette remained pretty neutral. Color fringing was mostly under control, with minor traces of longitudinal aberration seen at longer focal lengths around borders, but nothing dramatic.

 

ISO 200, 1/2500, f/2.8, 24mm (Nikon D3)
ISO 200, 1/2500, f/2.8, 24mm (Nikon D3)

 

Lab Tests

Please note that MTF50 results for APS-C and Full-Frame cameras as well as cameras from different manufacturers are not cross-comparable despite the same normalized [0:1] range used to report results for all types of cameras.

 

Nikon APS-C: Coming soon...

 

Nikon FF: Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF showed somewhat mixed results on a full frame Nikon D3. Image quality in the center as well  as around borders was very solid at the widest focal length, pretty much throughout the tested aperture range. Unfortunately, things turn to worse from that point on. At 35mm the lens still showcases excellent center image resolution, however border image quality starts to suffer at wider apertures - at f/3.2 quality is rather average, but improves to good levels by f/4 and then from f/5.6 through f/11 remains top notch. By 50mm, center resolution still stays on solid levels throughout the aperture range, but border quality at the widest aperture settings deteriorated further and by 85mm borders were noticeably soft from f/4 through f/5.6, reaching OK levels by f/8. Conclusion? Not what I'd call a superb performer - if you're chasing resolution, then you'd be better off at wider focal lengths.

 

Normalized raw MTF50 @ 24mm
Normalized raw MTF50 @ 24mm

 

Normalized raw MTF50 @ 35mm
Normalized raw MTF50 @ 35mm

 

Normalized raw MTF50 @ 50mm
Normalized raw MTF50 @ 50mm

 

Normalized raw MTF50 @ 85mm
Normalized raw MTF50 @ 85mm

 

The lens showed rather noticeable barrel distortion at its widest focal length (~1.225%), which turned into a pretty noticeable pincusion distortion at 85mm (~1.05%). Middle ranges of the zoom range fared better, with very slight barrel distortion at 35mm (~0.09%) and minor pincusion distortion at 50mm (~0.1%).

 

Distortion (FF) @ 24mm (left), 35mm (right)
Distortion (FF) @ 24mm (left), 35mm (right)

 

Distortion (FF) @ 50mm (left), 85mm (right)
Distortion (FF) @ 50mm (left), 85mm (right)

 

Chromatic aberration on Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF was somewhat of a mixed bag. Generally speaking, the lens handled CA better at the short end of the zoom range, with both center as well as border CA at 24mm being quite well under control. But, once zoomed to 35mm and beyond, chromatic aberration of the lens started to creep up - center CA shot up to ~0.8px at widest aperture, while border CA often exceeded ~1px.

 

Chromatic Aberration (FF) @ 24mm
Chromatic Aberration (FF) @ 24mm

 

Chromatic Aberration (FF) @ 35mm
Chromatic Aberration (FF) @ 35mm

 

Chromatic Aberration (FF) @ 50mm
Chromatic Aberration (FF) @ 50mm

 

Chromatic Aberration (FF) @ 85mm
Chromatic Aberration (FF) @ 85mm

 

Here are 100% crops, taken with a full frame Nikon D3, comparing image borders at 24mm, 35mm, 50mm and 85mm.

 

Image borders @ 24mm (100% crop): f/2.8 vs f/8
Image borders @ 24mm (100% crop): f/2.8 vs f/8

 

Image borders @ 35mm (100% crop): f/3.2 vs f/8
Image borders @ 35mm (100% crop): f/3.2 vs f/8

 

Image borders @ 50mm (100% crop): f/4 vs f/8
Image borders @ 50mm (100% crop): f/4 vs f/8

 

Image borders @ 85mm (100% crop): f/4 vs f/8
Image borders @ 85mm (100% crop): f/4 vs f/8

 

Alternatives

As mentioned in the intro section, Nikon introduced a short-lived replacement for Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF - Nikon AF-S Zoom Nikkor 24-85mm f/3.5-4.5G ED IF is still available on used markets and is certainly worth examining when considering an standard zoom lens. Two other interesting standard zooms in Nikon's lineup worth examining are Nikon AF-S Zoom Nikkor 24-70mm f/2.8G ED and Nikon AF-S VR Zoom Nikkor 24-120mm f/3.5-5.6G ED IF. Nikon obviously offers a plethora of other zoom lenses, quite a few of them in the DX format, suitable for cropped sensor cameras. Outside of the Nikon camp, you might want to take a look at Tamron's SP AF 28-75mm f/2.8 XR Di LD ASPH and Sigma's 24-70mm f/2.8 EX DG HSM.

 

Recommendation

Nikon AF Zoom Nikkor 24-85mm f/2.8-4D IF tries to be everything a photographer might want to have in an all-purpose standard zoom lens. Unfortunately, it falls short a bit in some areas. Image resolution, while excellent at wider end of the zoom range degrades towards the longer end, particularly around borders. Rather abysmal performance at closeup distances as wekk as pronounced barrel at 24mm and pincushion at 85mm distortion do not help either. So where does this leave you? If you are primarily shooting in the 24mm to 50mm range, and need longer end only occasionally, and even then would not mind shooting at smaller apertures, then you might be OK with the shortcomings of this lens. Or, even if you are using an APS-C type camera, which typically would be more forgivable of the softness around image borders due to its sensor's smaller coverage of the imaging circle of the lens.  But overall, this feels like a rather average lens.