PW

Leica Telescope-Ocular To-R

The Ocular To-R (Leica order no. 14234) is an adapter that makes it possible to use standard, telephoto, or zoom-lenses as telescopes. It attaches to Leica R-lenses via the bayonet mount. The Ocular contains a Schmidt-Pechan-prism that rotates the image by 180°, so that the latter appears upright and correctly sided, as well as an eyepiece with a focal length of 12.5mm. It has a -3 to +3 diopter adjustment. Focus is achieved via the focusing mechanism of the lens. The adapter is no longer in production, but can be found pre-owned in excellent condition for 300-500 USD (check here for current offers on ebay).

The effective magnification achieved by attaching the Leica Ocular depends on the focal length of the lens. It is calculated as the ratio between the focal length of the lens and the focal length of the Ocular. For example, a 90mm lens would achieve a magnification of 7.2 (=90mm/12.5mm), and a 400mm lens a ratio of 32.

Eyepiece
Leica Ocular Eyepiece[longmilan84]
noscript
Leica Ocular Eyepiece[longmilan84]

Ocular TO-R Specifications

The body of the adapter is a solid, all metal construction with the eyepiece cover being of high-quality rubber. It's core specifications are the following:

  • optical construction with 3 elements;
  • focal length of 12.5mm;
  • eyepiece magnification of 20x;
  • exit pupil diameter of 3.78mm;
  • usable aperture of 1/3.3;
  • field of view diameter of 12mm;
  • weight of 100g (3.5 oz).

The Leica Telescope-Ocular works rather well and can quickly turn a telephoto lens into a spotting scope. In good light, it can also be used in combination with Leica's 1.4x or 2x APO-Extenders. With long focal lengths, it achieves magnification ratios that are generally beyond those of binoculars, but the setup tends to require a tripod for comfortable use due to the heavy weight of the lenses. Also, some photographers report that it takes some time to get used to the "tunnel perspective" that the Ocular To-R provides as a result of a field of view diameter that is smaller than the display in a camera viewfinder. It might, hence, be desirable and useful to try out the Ocular To-R, if possible, before buying it in order to avoid disappointment later on.

Overview of R-System Tele-Photo Lenses
Tele-photo primes Leica
Reference
(#)
Filter
Type
(size)
Lens
Dimensions
(dia x len)
Lens
Weight
(g)
Production
Period
(years)
Price
2009
(USD)
Used
Price
(ebay)
Leica Macro-Elmarit-R 60mm f/2.8 11347 S7/E55 68 x 62 mm 400 g 1972-2009 3195 check
Leitz Elcan-R 75mm f/2 C-341 E60 64 x 77 mm 700 g 1965-1965 $$$$ check
Leica Summilux-R 80mm f/1.4 11349 E67 75 x 69 mm 700 g 1980-2009 4695 check
Leica Summicron-R 90mm f/2 11254 S7/E55 70 x 63 mm 560 g 1970-2000 3495 check
Leica APO-Summicron-R 90mm f/2 11350 E60 70 x 59 mm 520 g 2002-2009 3895 check
Leitz Wetzlar Elmarit-R 90mm f/2.8 (I) 11229 S7 65 x 72 mm 500 g 1964-1983 $$ check
Leica Elmarit-R 90mm f/2.8 (II) 1154 E55 67 x 57 mm 450 g 1980-1998 $$ check
Leica APO-Macro-Elmarit-R 100mm f/2.8 11352 E60 73 x 105 mm 760 g 1987-2009 3995 check
Leitz Wetzlar Macro-Elmar-R 100mm f/4 11232 E55 68 x 120 mm 670 g 1978-1995 $$$ check
Leitz Canada Elmarit-R 135mm f/2.8 (I) 11111 S7 65 x 91 mm 655 g 1964-1968 $$ check
Leica Elmarit-R 135mm f/2.8 (II) 11211 E55 67 x 93 mm 730 g 1968-1998 $$ check
Leica APO-Summicron-R 180mm f/2 11354 E100 116 x 179 mm 2500 g 1994-2009 8295 check
Angenieux APO IF 180mm f/2.3 A180LR E82 86 x 149 mm 995 g 1986-1992 $$$ check
Leitz Wetzlar Elmarit-R 180mm f/2.8 (I) 11919 S8 78 x 134 mm 1325 g 1966-1979 $$$ check
Leitz Wetzlar Elmarit-R 180mm f/2.8 (II) 11923 E67 75 x 121 mm 810 g 1979-1998 $$$ check
Leica APO-Elmarit-R 180mm f/2.8 (I) 11273 S8 76 x 132 mm 970 g 1998-2004 $$$ check
Leica APO-Elmarit-R 180mm f/2.8 (II) 11357 E67 76 x 132 mm 970 g 2004-2009 5295 check
Leitz Elcan-R 180mm f/3.4 C-303 E60 63 x 115 mm 750 g 1965-1965 $$$$ check
Leitz Canada APO-Telyt-R 180mm f/3.4 11242 S7.5/E60 68 x 135 mm 750 g 1975-1980 $$$ check
Leitz Wetzlar Elmar-R 180mm f/4 11924 E55 86 x 100 mm 540 g 1976-1996 $$ check
Leitz Canada Telyt-R 250mm f/4 (I) 11920 S8/E55 66 x 100 mm 1380 g 1970-1979 $$ check
Leitz Canada Telyt-R 250mm f/4 (II) 11925 E67 75 x 195 mm 1230 g 1980-1994 $$ check
Super-tele primes Leica
Reference
(#)
Filter
Type
(size)
Lens
Dimensions
(dia x len)
Lens
Weight
(g)
Production
Period
(years)
Price
2009
(USD)
Used
Price
(ebay)
Leica APO-Telyt-R 280mm f/2.8 11245 E112 125 x 261 mm 2750 g 1984-1992 $$$$ check
Leica APO-Telyt-R 280mm f/2.8 Module 11846 rear 125 x 276 mm 3740 g 1996-2009 11290 check
Leica APO-Telyt-R 280mm f/4 11360 E77 88 x 208 mm 1875 g 1996-2009 6995 check
Leitz Telyt-R 350mm f/4.8 11915 E77 84 x 286 mm 1820 g 1980-1993 $$$ check
Leica APO-Telyt-R 400mm f/2.8 11256 rear 125 x 314 mm 6240 g 1992-1996 $$$$ check
Leica APO-Telyt-R 400mm f/2.8 Module 11847 rear 157 x 344 mm 5800 g 1996-2009 17390 check
Leica APO-Telyt-R 400mm f/4 Module 11857 rear 157 x 382 mm 3860 g 1996-2009 12490 check
Leitz Wetzlar Telyt 400mm f/6.8 11960 S7 78 x 384 mm 1830 g 1968-1994 $$$ check
Leitz Wetzlar MR-Telyt-R 500mm f/8 11243 E77 87 x 121 mm 750 g 1980-1996 $$ check
Leica APO-Telyt-R 560mm f/4 Module 11848 rear 157 x 382 mm 6360 g 1996-2009 18590 check
Leica APO-Telyt-R 560mm f/5.6 Module 11858 rear 125 x 374 mm 4050 g 1996-2009 14290 check
Leica APO-Telyt-R 800mm f/5.6 Module 11849 rear 157 x 442 mm 6550 g 1996-2009 20390 check
Leitz Wetzlar Telyt-S 800mm f/6.3 11921 built-in 152 x 790 mm 6860 g 1972-1977 $$$ check
Minolta RF Rokkor-X 800mm f/8 for Leica R RF800LR rear 127 x 178 mm 1960 g 1973-1981 $$ check
Tele zoom Leica
Reference
(#)
Filter
Type
(size)
Lens
Dimensions
(dia x len)
Lens
Weight
(g)
Production
Period
(years)
Price
2009
(USD)
Used
Price
(ebay)
Leica Vario-APO-Elmarit-R 70-180mm f/2.8 11279 E77 89 x 190 mm 1870 g 1995-2009 8795 check
Angenieux 3x70 70-210mm f/3.5 A3X70LR E62 80 x 164 mm 783 g 1985-1989 $$$ check
Leica Vario-Elmar-R 70-210mm f/4 11246 E60 74 x 157 mm 720 g 1984-2000 $$$ check
Leica Vario-Elmar-R 75-200mm f/4.5 11226 E55 70 x 157 mm 725 g 1978-1984 $$$ check
Leica Vario-Elmar-R 80-200mm f/4 11281 E60 71 x 165 mm 1020 g 1996-2009 2695 check
Leitz Wetzlar Vario-Elmar-R 80-200mm f/4.5 11224 E55 72 x 157 mm 710 g 1974-1978 $$$ check
Leitz Wetzlar Vario-Elmar-R 105-280mm f/4.2 11268 S8 89 x 238 mm 1950 g 1996-2006 $$$$ check

Further reading

The Leica Ocular works well with many of the R-series lenses, including the APO-Telyt telephoto optics. It can also be used in combination with Leica's tele-converters, if the light is good enough. Moreover, if you are more generally interested in the now discontinued Leica reflex system, you might want to check out the comparison of Leicaflex and Leica R cameras.

You are here  »   »