NIKON-S+LEICA-M Nikkor-H.C 5cm

A review and photo examples using the NIKON H.C 50mm f2 with the HEXAR RF limited.

Please see the disclaimer regarding advertising here.

This is an irregular way to use a lens, and we would like to point out that anyone attempting similar photography does so at their own risk.

Gallery

The example photos were taken using a HEXAR RF limited and a LOMOGRAPHY Lady Grey B&W 400.

1．Overview

The NIKON H.C 5cm f2 is a standard lens with a focal length of 50mm for the Nikon S mount, released in 1950.

To use this NIKON H.C 5cm f2 lens with a Leica M mount camera, a mount adapter with a helicoid function and rangefinder coupling mechanism is required.

This time, I will report on the results of shooting with the NIKON H.C 50mm f2 attached to a HEXAR RF Limited using a Nikon S-Leica M helicoid + rangefinder coupling mechanism adapter of unknown brand that I purchased second-hand.

The main specifications of the lens are a Sonnar type lens with 6 elements in 3 groups and 10 aperture blades. The minimum shooting distance is limited by the mount adapter side and is 0.9m.

The lens in the photo is a lens made after 1956 with a lightweight lens barrel and painted black.

I used LOMOGRAPHY LADY GREY B&W 400 film.

2．Usability

The combination of the HEXAR RF limited, Nikon S adapter, and lens that I own has no problems with the rangefinder coupling mechanism, and I can focus at the desired position even at full aperture.

The viewfinder frame has a 35mm frame tab, so when using a 50mm lens, you can either press the frame switch lever on the HEXAR RF to display the 50mm frame, shoot casually, or use an external viewfinder.

I only used one roll of monochrome film, but the precise resolution and sharp contrast are sufficient even with ISO 400 film. I haven’t shot with it yet, but I’m looking forward to seeing what kind of results I’ll get with color negative film.

The first thing that confused me about this lens and adapter combination is that the direction of rotation of the helicoid on the Nikon S moves from infinity to the close-up direction when turned left, which is the opposite of the helicoid on the Leica M. On the Leica M lens, the direction of rotation moves from infinity to the close-up direction when turned right.

It doesn’t bother me much when I’m using only this lens, but when I take a Leica M lens and a Nikon S lens + adapter out with me, it causes some confusion in operation, so I try not to take a Leica M lens out with me when I’m using an S lens + adapter.

3．Summary

In conclusion, to sum up the use of the NIKKOR H.C 5cm (50mm) f2 S mount with the LEICA M mount, if the mount adapter is normal, accurate focusing is possible with the double image alignment of the rangefinder of the rangefinder camera, and it can be used without problems from infinity. The 50mm F2 specification provides stable depiction even at the widest aperture.

○About Nikon S lenses

To give a very simple explanation of Nikon S lenses, there are internal claw lenses that do not have a helicoid on the lens, and external claw lenses that have a helicoid on the lens side.

The NIKON H.C 5cm introduced here is an internal claw lens that does not have a helicoid on the lens. The NIKON-S series cameras that use this lens have a helicoid on the camera side to extend the lens because it is an internal claw lens. The center part of the camera in the image below is the lens extension mechanism (helicoid).

When using a mount adapter, it is always necessary to be aware that you are using it in a way that the manufacturer did not expect, and to carefully check the installation, etc.

Most adapters with helicoids and rangefinder coupling mechanisms for Leica M are made overseas and are often imported by individuals or shops. Prices tend to be high in general.

In particular, with adapters that feature a rangefinder linkage mechanism, there is a risk of problems such as the rangefinder becoming misaligned and the focus being slightly off depending on the compatibility between the rangefinder linkage mechanism and the camera, so it is safe to check the condition of the actual product and check the return policies if it does not work with your camera.

By Sshenoy Sudhir Shenoy – Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=8524277

There are three types of Nikon S to Leica M mount adapters:

Nikon S-Leica M with helicoid + rangefinder interlocking mechanism (for both internal and external claw lenses)
Nikon S-Leica M shape conversion only (for external claw lenses only)
Nikon S-Leica M shape conversion only (for internal claw lenses only)

Regarding compatibility between Nikon S and Contax C, we have provided links to what we believe to be reliable information in the Reference Information section.

Specification and Competitor

Item	NIKON H.C	NIKON S.C
focal length(mm)	50	50
Maximum aperture	2	1.4
Minimum aperture	16	16
Aperture blade	10	12
Lens Construction	6 elements in 3 groups	7 elements in 3 groups
Minimum distance(m)	0.9	0.9
Lens length(mm)	35 M mount included	35 M mount included
Lens max diameter(mm)	47	47
Filter type	40.5	43
Hood	Trumpet type/Spring stopper	Trumpet type/Spring stopper
Weight(g)	211 M mount included	225 M mount included
Release date	1946	1950
Production numbers	–	–
Price	–	–