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527:
308:, so lenses designed for 35 mm film could not be used with their native field of view without additional optics used. Implementing a telecompressor helped to mitigate these limitations. One effect of a telecompressor is that it reduces the diameter of the
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of the imaging system. As the addition of the telecompressor will increase the necessary back focus, the original focal length will increase by a certain amount, and then this new focal length would be used in the above formula.
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36:(OTF) performance. It is also widely known under the name “Speed Booster”, which is the commercial name of a line of telecompressors by the manufacturer Metabones. Popular applications include
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system that has a combination of mirror and lens, the determination of reduction is more complicated, due to the fact that the telescope has a
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Side view with aperture control rocker (above optical axis) and USB socket with rubber cover (below optical axis)
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48:. In astrophotography, these qualities are most desirable when taking pictures of nearby large objects, such as
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428:
264:, the calculation is the same. However, since the telecompressor increases the field of view, there could be
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cameras. By combining a telecompressor within a lens adapter, mirrorless cameras can use the lenses of both
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than the lens alone; this places restrictions on lenses and cameras that focal reducer might be used with.
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52:. The effects and uses of the telecompressor are largely opposite to those of the
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Mount for Micro Four Thirds camera bodies with eleven gold contacts
229:{\displaystyle {f_{n}}={f_{o}}\left(1-{\frac {d}{f_{r}}}\right),}
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Telecompressors were used in early digital SLR systems like the
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Mount for Canon EF lenses (full-format) with eight gold contacts
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60:. A combined system of a lens and a focal reducer has smaller
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or simple camera lens, the new effective focal length
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that include telecompressors are useful with digital
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429:"Focal Reducer with Fast Newtonian?"
86:Digital telecompressor (0,64x) for
533:This film technology article is a
257:= focal length of telecompressor.
76:digital single-lens reflex cameras
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446:Rentals, Lens (22 January 2013).
292:Keplerian (relay) telecompressors
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32:, and in some instances improve
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414:"K3's Astronomy - Telescopes"
537:. You can help Knowledge by
484:. You can help Knowledge by
379:Charles, Jeffrey R. (2000).
78:(DSLRs) and film-based SLR (
135:Calculating focal reduction
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383:Practical Astrophotography
80:Single-lens reflex cameras
34:optical transfer function
584:Astronomical instruments
412:Peter Katreniak (2001).
272:and the telescope tube.
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599:Film technology stubs
589:Photography equipment
281:variable focal length
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262:reflecting telescope
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389:Springer Publishing
448:"Metabones Magic?"
360:Mirrorless Journey
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594:Photography stubs
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453:22 September
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363:. Retrieved
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310:image circle
306:sensor sizes
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277:catadioptric
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90:lenses with
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26:focal length
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326:Barlow lens
314:crop factor
58:Barlow lens
42:videography
38:photography
28:, increase
578:Categories
365:2018-05-31
342:References
266:vignetting
72:mirrorless
62:back focus
30:lens speed
199:−
144:telescope
141:refractor
320:See also
300:and the
88:Canon EF
50:nebulae
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275:For a
260:For a
239:where
139:For a
44:, and
535:stub
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455:2016
393:ISBN
285:axis
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56:or
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