Difference between revisions of "Collimation"
(a useful technique) |
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| + | The verb to '''Collimate''' is derived from the Latin ''collineare'', to align.<ref name=COD>Concise Oxford Dictionary. Ninth edition, 1995, Oxford University Press, p259.</ref> It refers to the parallel alignment of light rays (making them ''collinear''), or of two or more optical instruments (such as a large telescope with the smaller one used to direct it). | ||
| + | A '''collimator''' is an instrument for producing parallel rays, for use in adjustment of other instruments.<ref name=COD/> These parallel rays may be used to simulate the rays from an object at infinite distance, and so are appropriate in adjusting the focus scale of a camera lens at infinity. | ||
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| + | It has become a common misuse to refer to this adjustment itself as 'collimation'. It is possible to check the infinity-focus position of a lens using the [[split prism]] focus aids commonly provided in a manual-focus SLR camera. | ||
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| + | ==Notes== | ||
| + | <references/> | ||
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| + | <!-- commenting out old text so I can revert this easily | ||
'''Collimation''' of a lens means adjusting it so that its infinity setting is correct. In order to collimate a lens, you need a special-purpose collimator, an infinitely distant light source, or an [[SLR]] and some ingenuity. | '''Collimation''' of a lens means adjusting it so that its infinity setting is correct. In order to collimate a lens, you need a special-purpose collimator, an infinitely distant light source, or an [[SLR]] and some ingenuity. | ||
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==Links== | ==Links== | ||
| − | *[http://elekm.net/zeiss-ikon/repair/collimate/ Lens collimation | + | *[http://elekm.net/zeiss-ikon/repair/collimate/ Lens collimation] (with particular reference to a Contax-mount 50mm Sonnar), by [http://elekm.net/pages/ Mike Elek] |
| − | *[http://members.tripod.com/rick_oleson/index-123.html Lens collimation | + | *[http://members.tripod.com/rick_oleson/index-123.html Lens collimation], by [http://rick_oleson.tripod.com/ Rick Oleson] |
[[Category:Techniques]] | [[Category:Techniques]] | ||
Revision as of 17:59, 29 September 2014
The verb to Collimate is derived from the Latin collineare, to align.[1] It refers to the parallel alignment of light rays (making them collinear), or of two or more optical instruments (such as a large telescope with the smaller one used to direct it).
A collimator is an instrument for producing parallel rays, for use in adjustment of other instruments.[1] These parallel rays may be used to simulate the rays from an object at infinite distance, and so are appropriate in adjusting the focus scale of a camera lens at infinity.
It has become a common misuse to refer to this adjustment itself as 'collimation'. It is possible to check the infinity-focus position of a lens using the split prism focus aids commonly provided in a manual-focus SLR camera.
Notes
Links
- Lens collimation (with particular reference to a Contax-mount 50mm Sonnar), by Mike Elek
- Lens collimation, by Rick Oleson
