AF Micro-Nikkor ED 70-180/4.5-5.6 D
|Lens construction:||18 elements in 14 groups (1 ED element)|
|Focus distance:||0.37 m to infinity|
|Angle of View:||34° 20' to 13° 40'|
|Max. reproduction ratio:||1:1.33|
|Aperture scale:||f/4.5 to f/32|
|Attachment size:||62 mm|
|Diaphgram blades:||9 (circular blades)|
|Lens hood:||HB-14 (supplied)|
|Tripod mounting collar:||built-in (rotatable 300°)|
|Dimensions:||75 mm (dia.) x 175 mm (length)|
|Weight:||Approx. 990 g (34.9 oz)|
The 70-180 is an ideal lens for mountain hikes and covers landscape as well as close-up photography with ease. At infinity, the quality of the lens is good when it is set to apertures ranging from f/8 to f/11. Wide open, field curvature becomes visible and image borders are less crisply defined for focal lengths > 105 mm. It outperforms the image quality of 70-210 or 70-300 amateur zooms having comparable speed. Color rendition is outstanding.
However, at focus distances approaching infinity, this lens is bettered by both AI 105/2.8 Micro and AF ED 80-200/2.8 D. The distorsion at infinity is negligible (click here to see the behaviour at 180 mm).
The 9-blade diaphgram ensures a pleasing rendition of the out-of-focus areas. For this reason, the 70-180 is a nice tool for portraits.
The close-up performance of this lens is surprisingly good. When working with the lens on the tripod, we can turn the zoom ring and/or rotate the lens using the tripod collar in order to fine-tune the composition. It can focus at 0.37 m with a maximum reproduction ratio, R, of 0.75 (or 1/1.33). This fact has to be ascribed to the deep shortening of focal length at the near limit (see below). Both sharpness and contrast of this fine macro lens in close-focus shots is very good. I have performed a comparison between this lens and the AI Micro 105/2.8 at R > 0.5. The micro-contrast of the 70-180 was slightly higher than the AI 105/2.8 + PN-11.
At R = 1:2, the working distance (WD), i.e. the distance between the front element and the subject, is 23-24 cm, a value comparable to both AI and AF 105/2.8 Micro-Nikkors. Therefore, the 70-180 is suitable for close-up shots of shy animals. It also performs well with the Nikon close-up achromatic lenses. When the 5T is employed, longer working distances are obtained (see below).
Nikon advocates the use of 6T lens to get to life-size (1:1). With the 5T lens, a R =1:1.1 (= 0.9 X) can be achieved, with a slightly higher image quality.
Wild Orchid (Ophrys holoserica)
Oak (Quercus pubescens)
Wild Orchid (Orchis papilionacea)
Skink (Chalcides ocellatus)
All images © Copyright Riccardo Polini
Effective focal length of Micro-Nikkor 70-180 in close-ups.
The Micro-Nikkor 70-180 has a floating element design. This fact causes a progressive reduction of the focal length (FL) when we focus at close distances. The shorter the focused distance, the larger the reduction of the FL.
I have calculated the effective focal lengths of the zoom as a function of the focused distance. In the plot below the results obtained for two zoom ring positions are reported. The blue triangles refer to 105 mm; the pink ones to 180.
The data show that - at the minimum focused distance - the effective focal lengths are 79 and 90 mm when the zoom ring is set at 105 and 180 mm, respectively.
Focusing and working distances of 70-180 in close-ups.
The Micro-Nikkor 70-180 works fine when coupled to the Nikon 5T close-up lens. It is worth noting that both focusing and working distance are larger when the 5T attachment lens is used. This fact is rather important when we shoot shy animals in their habitat. For example, at R ~ 1:2 the working distance (WD) is 23-24 cm when the zoom ring is set at 180 mm (focusing distance, FD ~ 47-48 cm); with the 5T lens, FD is about 54 cm and WD is around 30-31 cm.
The measured focusing distance (FD) and working distance (i.e. the distance between the attachment lens and the subject, WD) are plotted below as a function of the magnification (or reproduction ratio, R). All the data have been measured with the zoom ring set at 180 mm. For each R value, both FD and WD are larger when the 5T lens is used.