Pekka Buttler, 01/2026
This lens was kindly provided for cataloguing by Vladimir at #photogears
Specifications
The table below summarizes the lens’ key specifications (measurements based on pictured version of the lens):
| Brand: | ENNA München (Enna Werk München) | Lens name | Sandmar 100mm F:4.5 |
| Focal length(s)1 | 100 mm | Angle-of-view2 | 24 ° |
| Maximum Aperture | f/4.5 | In Production | ca 1947–1957 |
| Lens mount (this lens) | Argus 33 mm thread | Other lens mounts | none |
| Length3 | 44,3 mm | Diameter4 | 41,0 mm |
| Filter ring diameter | 30 mm | Weight | 262 grams |
| Lens element count | 4 | Lens group count | unkown |
| Aperture blades (S/R/C)5 | 10 S | Focus throw | 310 ° |
| Minimum focusing distance (measured) | 1 m | Maximum magnification (measured) | 1:8 |
| Has manual aperture ring | YES | Has Manual focus ring | YES |
| Aperture mechanism type | manual with click stops | Aperture click stops | 4.5-5.6-8-11-16-22. |
Further notes:
• Enna was still a relatively young company (see the JAPB company profile on Enna München) recovering from a war that had seen its factory bombed out and its clientele impoverished.
• At the same time, in the US, there was a camera company that had an interchangeable lens camera without any real lens lineup. Hence the Argus-Enna collaboration which saw Enna offer both wide-angle and tele lenses (1 each) for the Argus C3 camera, and Argus heavily promoting these lenses.
• To suit American tastes, the lens lineup was named ‘Sandmar’ (what’s wrong with Ennalyt or Lithagon?)
• Detailed information on this lens is sparse. For instance, while it being a 4 elements design, trustworthy schematics or specifications are difficult to come by. If you have hard information, you’re welcome to be in touch.
Versions and variations
The 100 mm f/4.5 Enna Sandmar was also sold by Argus as the Argus Sandmar, but they are fundamentally the same lens.
Early samples say that they were manufactured in the “US zone, Germany”; later samples say they were made in “Germany”.
Adapting the ENNA München Tele-Sandmar 100 mm f/4.5
Adapting Argus C lenses
Even though the Argus C lenses are small, they are full frame lenses, and the Argus C mount has a thread mount with a diameter of ca 33 mm, and a flange focal distance of 41,9 mm.
At that, the Argus C mount’s flange focal distance is too short for adapting Argus C to any SLRs or dSLRs without losing infinity focus abilities (and then some). Theoretically an adapter with optics could correct for this, but currently no such adapters exist.
If, on the other hand, you intend to use your Argus C lens on a mirrorless camera, you only need to find a suitable adapter. Currently none of the big adapter makers offer Argus C adapters, but if you hunt on eBay and ilk, you should be able to find cottage industry adapters for most popular mirrorless mounts. Alternatively, you can 3D print your argus adapter.
History of ENNA München
ENNA München (also: Enna Werk München) is one of the 1950s and 60s most prominent and innovative German optics companies. ENNA is especially well-known for being the West-German pioneer in developing retrofocus wide-angle lenses.
You can read more details in the ENNA München company profile.
Footnotes
- Focal length is (unless stated otherwise) given in absolute terms, and not in Full-frame equivalent. For an understanding of whether the lens is wide/tele, see ‘Angle-of-view’. ↩︎
- Picture angle is given in degrees (based on manufacturers’ specs) and concerns the diagonal picture angle. Rule of thumb:
> 90 ° ==> Ultra-wide-angle
70–90 ° ==> Wide-angle
50–70 ° ==> Moderate wide-angle
40–50 ° ==> ‘Standard’ or ‘normal’ lens
20–40 ° ==> Short tele lens
10-20 ° ==> Tele lens
5-10 ° ==> Long tele lens
< 5 ° ==> Ultra-tele lens ↩︎ - Length is given from the mount flange to the front of lens at infinity. ↩︎
- Diameter excludes protrusions such as rabbit ears or stop-down levers. ↩︎
- S=straight; R=rounded; C=(almost)circular at all apertures. ↩︎