Hands on: Both the 45mm f/4 and 65mm f/4 ZenzanonRF lenses are solidly constructed and beautifully finished in satin black. They're both quite compact and average in weight for their respective sizes, which are nearly identical. The 45mm's rear element extends farther back into the body and, since it incorporates less glass, it weighs a bit more than the 65mm. Both lenses have wide, grippably textured rubberized focusing rings, and they focus smoothly, with a well-damped action from infinity to 1 meter in a clockwise quarter-turn. The narrower milled aperture rings at the rear of each lens are easy to grasp and have detents at half-stop intervals between f/4 and f/32. All scales are reasonably large and legibly engraved in white-on-black, with the exception of easy to read orange-on-black footage scales. De pth-of-f i e I d scales are comprehensive, and there is an infrared focusing index. Both lenses balance extremely well on the camera.
In the lab: Lines-per-millimeter resolution readings for both lenses indicate outstanding overall performance—excellent at all apertures, center and edges from f/4 to f/16, and good to excellent at f/22 and f/32. The 45mm f/4 showed slight barrel distortion (0.75%), while the 65mm f/4 showed minimal barrel distortion (0.45%). Exposure accuracy at the film plane was very good with the 45mm and outstanding with the 65mm. The 45mm underexposed by about VÁ stop at maximum aperture due to light falloff, by Vio stop from f/5.6 to f/16, and by less than Vio stop from f/22 to f/32. The 65mm exhibited less than Vio stop of exposure deviation at all apertures.
At the closest focusing distance of 39 inches (1:1 9.4X magnification), the 45mm lens delivered excellent center and corner sharpness at all apertures, except for the corners at f/32, which were very good. Optimum aperture was f/1 1 .
At the closest focusing distance of 39 inches (l :14X magnification), the 65mm lens gave excellent center and corner sharpness at all apertures—an outstanding performance. Optimum aperture was f/8.
In the field: With both the 45mm and 65mm, light fa 11 off was gone by f/5.6, and flare was very well controlled in all shooting situations, with virtually no ghosting visible. Test slides were sharp and contrasty at all apertures, except in corner images taken at f/32 with the 65mm lens, which were slightly soft. The accessory viewfinder for the 45mm lens haa noticeable barrel distortion, but it's bright, clear, comfortable to use, and has a wide range of dioptric adjustments. It lacks parallax adjustment but does have parallax-compensation lines for estimating composition at close distances.
Conclusion: These top-notch lenses are among the best we've tested for the 6x4.5cm format and they certainly add to the luster of the the RF645 system. O
POPULAR PHOTOGRAPHY’S unbiased test reports are based on actual field work and measurements carried out in our own laboratories. Only production equipment and materials similar to those available to the reader are tested. Unless noted otherwise, products tested have trademarks and specifications for sale in the U.S. The manufacturer has reserved the right to change the product specifications. Since optics and precision instruments vary from unit to unit, we strongly suggest that readers carry out their own tests on equipment they buy. Prices are manufacturers’ suggested list prices. Items are often available at lower prices through dealers.
Zenzanon-RF 65mm f/4
The RF645's standard lens sets high standards
65mm (65.50mm tested), f/4 (f/4.40 tested), 6 elements in 4 groups.
View angle: Diag: 56 degrees. Min aperture; f/32. Focusing turns 80 degrees counterclockwise; min focus 3 ft 3% in. Weight: 113/i6 0z.
Filter size: 58mm.
Mount available: Bronica-RF. List price: $587.
Street price: (only sold with camera).
Zenzanon-RF 45mm f/4
Bronica’s compact wideangle offers outstanding performance
45mm (44.50mm tested), f/4 (f/4.40 tested), 7 elements in 5 groups.
View angle: Diag: 75 degrees.
Min aperture: f/32. Focusing turns 80 degrees counterclockwise; min focus 3 ft 3% in.
Filter size: 58mm.
Mount available: Bronica-RF. Included lenshood and external viewfinder.
List price: $732.
Street price: $669.