Support article / SA-014
Lens mount and adapter compatibility
What the HV mount is, which lenses from other systems can be adapted to the H1, and which cannot. Updated for firmware 1.4.0.
The HV mount in numbers
HV is a three-lug bayonet with a throat diameter of 46.0 mm and a flange distance of 17.5 mm. It carries 11 electrical contacts. The bayonet locks with a 52-degree clockwise turn, seen from the front of the camera.
Because the flange distance is short, almost any lens designed for a single-lens reflex or rangefinder can be adapted with a simple spacer. The opposite is not true: mounts with a flange distance close to, or shorter than, 17.5 mm cannot be adapted at all.
Mounts that adapt
| Mount | Flange distance | Adapter | Notes |
|---|---|---|---|
| M-mount rangefinder lenses | 27.80 mm | Halvane HV-M adapter | Reads six-bit lens codes from firmware 1.3.0. Infinity calibrated per adapter. |
| M39 screw mount (LTM) | 28.80 mm | HV-M adapter plus an M39 to M ring | Use a 28/90, 35/135 or 50/75 ring so the code sensor is not triggered. |
| Nikon F | 46.50 mm | Third-party passive adapter | Manual focus and aperture only. G-type lenses need an adapter with an aperture lever. |
| Canon EF | 44.00 mm | Third-party passive adapter | No electronic contacts. Aperture cannot be set on EF lenses, so they stay wide open. |
| Pentax K | 45.46 mm | Third-party passive adapter | Works fully manually. |
| Olympus OM | 46.00 mm | Third-party passive adapter | Works fully manually. |
| Contax/Yashica | 45.50 mm | Third-party passive adapter | Works fully manually. |
| M42 screw mount | 45.46 mm | Third-party passive adapter | Lenses with an auto/manual switch must be set to manual. |
| Medium format (various) | Over 60 mm | Third-party passive adapter | Possible. Use the tripod collar of the lens, not the H1, to support anything over 1.2 kg. |
Mounts that do not adapt
| Mount | Flange distance | Why not |
|---|---|---|
| Sony E | 18.00 mm | Flange distance is only 0.5 mm longer than HV. No adapter can be built that thin. |
| Nikon Z | 16.00 mm | Shorter than HV. The lens would have to sit inside the camera. |
| Fujifilm X | 17.70 mm | 0.2 mm longer than HV, and an APS-C image circle. |
| Canon RF and L-mount | 20.00 mm | A 2.5 mm adapter is mechanically possible, but no electronic protocol is supported and we know of no adapter that fits the HV throat. |
| Micro Four Thirds | 19.25 mm | Image circle covers only about a quarter of the H1 sensor. |
| HV lenses on other cameras | HV is a closed mount. HV lenses cannot be adapted to other bodies. |
The Halvane HV-M adapter
We make one adapter ourselves: the HV-M, for M-mount lenses. It is 10.3 mm thick, machined from stainless steel, and costs EUR 249. An optical sensor in the adapter reads the six-bit code on coded M lenses and passes it to the camera, which then writes the focal length to the file and applies the matching vignetting profile. Code reading needs firmware 1.3.0 or later.
Every HV-M is calibrated for infinity on a collimator in Copenhagen. The calibration sheet with its measured value is in the box.
Using adapted lenses well
- Turn on Shoot without lens in Setup, page 3. Without it the shutter will not release on a passive adapter.
- Enter the focal length in the Adapted lens menu so stabilisation works correctly. The H1 stores up to 20 named lens profiles, each with focal length, maximum aperture and a vignetting correction from 0 to 5.
- Assign 12x magnification to the rear dial press for critical focus at wide apertures.
- The H1 can show the effective aperture in the EXIF only if you set it on the front command dial before the shot. It does not measure it.
Lenses whose rear element protrudes more than 9.5 mm behind the M flange can touch the shutter guard of the H1. This includes several collapsible and early wide-angle M and M39 designs. Collapsible lenses must not be collapsed while mounted. If you are unsure, measure the protrusion before mounting, or write to support@halvane-optics.com with the lens name.
Weight on the mount
The HV mount is rated for a lens hanging freely of up to 1.2 kg. Anything heavier must be supported by its own tripod collar or a lens support. Damage to the mount from overloading is not covered by the warranty.
Corner colour shift
Some wide-angle rangefinder lenses produce magenta or green corners on digital sensors. The H1 sensor has a thin cover glass of 0.8 mm, which keeps this low, but lenses shorter than 28 mm may still show it. A flat-field correction can be applied in your raw developer.