The Gelmer shutter is known on the Semi Shiks by Kigawa and Roll Light Ref by Ōhashi. It gives T, B, 150, 100, 50, 25 speeds. The shutter plate is inscribed GELMER at the top and GELMER Mfr. at the bottom, perhaps for Gelmer Manufacturing. The speeds are sometimes inscribed on the shutter plate and sometimes engraved on the shutter rim.
Gelmer or Gelmar filters
Filters called Gelmer or Gelmar were distributed by Eikōdō in the late 1930s and early 1940s. Advertisements dated between June 1938 and October 1943 have been observed. The name is consistently written ゲルマー in katakana. The Roman spelling GELMAR appears on some advertising pictures, but some descriptions have the Roman name "Gelmer", perhaps by mistake. The filters are mentioned as "made in Germany" (独逸製) from 1938 to 1940, but this mention was later suppressed.
- On the shutter plate: Semi Shiks pictured in Furukawa, pp.7–9 of Camera Collectors' News no.261. On the speed rim: Roll Light Ref pictured in Sugiyama, item 2025.
- Sugiyama, item 2025.
- Advertisements reproduced in Kokusan kamera no rekishi, pp.81 and 99–100.
- Advertisements dated June 1939 and February 1940 reproduced in Kokusan kamera no rekishi, p.81.
- Asahi Camera (アサヒカメラ) editorial staff. Shōwa 10–40nen kōkoku ni miru kokusan kamera no rekishi (昭和10–40年広告にみる国産カメラの歴史, Japanese camera history as seen in advertisements, 1935–1965). Tokyo: Asahi Shinbunsha, 1994. ISBN 4-02-330312-7.
- Furukawa Haruo (古川保男). "Semi Sixteenth '16×2=32, 16×3=48'". In Camera Collectors' News no.261 (March 1999). Nishinomiya: Camera Collectors News-sha. Pp.5–9.
- Sugiyama, Kōichi (杉山浩一); Naoi, Hiroaki (直井浩明); Bullock, John R. The Collector's Guide to Japanese Cameras. 国産カメラ図鑑 (Kokusan kamera zukan). Tokyo: Asahi Sonorama, 1985. ISBN 4-257-03187-5.