Spencer Lens Company U.S. NAVY BU.SHIPS MARK 30 MOD 0 7X50 (View 1)
Manufacturer/Model: Spencer Lens Company U.S. NAVY BU.SHIPS MARK 30 MOD 0 7X50
Field of View: 7 deg 40 min = 134 m/1,000 m; APFOV 53.9 deg
Weight: 1241 gr
Exit Pupil: 7.14 mm
Serial #/Year of Manufacture: 285080 = 1944-1945
Notes: Historically, the Spencer Lens Company which was purchased by the American Optical Company in 1935 was an important American maker of microscopes, lenses and optical glass, and at the outbreak of World War II had the capacity to manufacture binoculars of innovative design such as the Navy Mark 30 7X50.
Rohan discusses the Navy Mark 30 on page 39 of his book “A Guide to Handheld Military Binoculars”. It was manufactured from 1943-1944, was considered waterproof, had anti-reflective coated optics, and was of smaller size with a wider field of view than most other WW II U.S. 7X50 binoculars. Excepting the Marks 41 and 45, the 7X50 binoculars made by Bausch & Lomb, Sard, Universal Camera, National Instrument, and Anchor Optical are optically and mechanically very alike (large Bausch & Lomb type chassis, 7.1 degrees FOV with good optics, same ocular design) differing mainly in provisions for weatherproofing, filters and graticules and are best exemplified by the excellent Bausch & Lomb Mark 28 (see www.flickr.com/photos/binocwpg/4861560565/in/set-72157623... ). Although the Spencer Mark 30 does not differ from them to the same extent as do the Marks 41 and 45, its variations are still distinct. See views 2 ( www.flickr.com/photos/binocwpg/5618969191/in/photostream ) and 3 (www.flickr.com/photos/binocwpg/5619531534/in/photostream/ ). Note that in addition to the Mark 30's different shape and size it has a longer ocular housing and greater diameter eyelens. View 4 (www.flickr.com/photos/binocwpg/5614511103/in/photostream/ ) shows the Mark 30 had differently sized ocular and objective prisms. The purpose of this is, I think, to reduce binocular size and weight (collection’s very compact Zeiss Oberkochen 8X30 also has differently sized prisms).
In use, the Mark 30 is more comfortable to carry and hold than the heavier and bulkier Mark 28. Optically, both seem to have equal brightness, sharpness and color rendition, and their “sweet spots”, the sharp central areas of view, seem to be of about the same size. However, the Spencer has a noticeably wider field of view (7.7 degrees vs. the Mark 28’s 7.16 degrees) but, as is often the case with a wider angle view, it also has a noticeably greater amount of softness at its edge of field. Nonetheless, I find the ergonomics and view of this Spencer Mark 30 preferable to that of the Mark 28.
The binocular came in a rubberized Hood case (see: www.flickr.com/photos/binocwpg/4856117376/in/photolist-7N... ) with a pair of neutral density grey filters which can be fitted over the eyecups in a compartment in the lid of the case.
Note: If you have a vintage binocular you either wish to sell or would just like some information about, I can be contacted at flagorio12@gmail.com .
Spencer Lens Company U.S. NAVY BU.SHIPS MARK 30 MOD 0 7X50 (View 1)
Manufacturer/Model: Spencer Lens Company U.S. NAVY BU.SHIPS MARK 30 MOD 0 7X50
Field of View: 7 deg 40 min = 134 m/1,000 m; APFOV 53.9 deg
Weight: 1241 gr
Exit Pupil: 7.14 mm
Serial #/Year of Manufacture: 285080 = 1944-1945
Notes: Historically, the Spencer Lens Company which was purchased by the American Optical Company in 1935 was an important American maker of microscopes, lenses and optical glass, and at the outbreak of World War II had the capacity to manufacture binoculars of innovative design such as the Navy Mark 30 7X50.
Rohan discusses the Navy Mark 30 on page 39 of his book “A Guide to Handheld Military Binoculars”. It was manufactured from 1943-1944, was considered waterproof, had anti-reflective coated optics, and was of smaller size with a wider field of view than most other WW II U.S. 7X50 binoculars. Excepting the Marks 41 and 45, the 7X50 binoculars made by Bausch & Lomb, Sard, Universal Camera, National Instrument, and Anchor Optical are optically and mechanically very alike (large Bausch & Lomb type chassis, 7.1 degrees FOV with good optics, same ocular design) differing mainly in provisions for weatherproofing, filters and graticules and are best exemplified by the excellent Bausch & Lomb Mark 28 (see www.flickr.com/photos/binocwpg/4861560565/in/set-72157623... ). Although the Spencer Mark 30 does not differ from them to the same extent as do the Marks 41 and 45, its variations are still distinct. See views 2 ( www.flickr.com/photos/binocwpg/5618969191/in/photostream ) and 3 (www.flickr.com/photos/binocwpg/5619531534/in/photostream/ ). Note that in addition to the Mark 30's different shape and size it has a longer ocular housing and greater diameter eyelens. View 4 (www.flickr.com/photos/binocwpg/5614511103/in/photostream/ ) shows the Mark 30 had differently sized ocular and objective prisms. The purpose of this is, I think, to reduce binocular size and weight (collection’s very compact Zeiss Oberkochen 8X30 also has differently sized prisms).
In use, the Mark 30 is more comfortable to carry and hold than the heavier and bulkier Mark 28. Optically, both seem to have equal brightness, sharpness and color rendition, and their “sweet spots”, the sharp central areas of view, seem to be of about the same size. However, the Spencer has a noticeably wider field of view (7.7 degrees vs. the Mark 28’s 7.16 degrees) but, as is often the case with a wider angle view, it also has a noticeably greater amount of softness at its edge of field. Nonetheless, I find the ergonomics and view of this Spencer Mark 30 preferable to that of the Mark 28.
The binocular came in a rubberized Hood case (see: www.flickr.com/photos/binocwpg/4856117376/in/photolist-7N... ) with a pair of neutral density grey filters which can be fitted over the eyecups in a compartment in the lid of the case.
Note: If you have a vintage binocular you either wish to sell or would just like some information about, I can be contacted at flagorio12@gmail.com .