Difference between revisions of "Collimation"
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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. | 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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| − | + | |image_source= http://www.flickr.com/photos/29504544@N08/3426534707/in/pool-camerawiki/ | |
| + | |image= http://farm4.staticflickr.com/3412/3426534707_f7fc24c69a.jpg | ||
| + | |image_align= center | ||
| + | |image_text= Collimator Mont 7515 | ||
| + | |image_by= Hans Kerensky | ||
| + | |image_rights= with permission | ||
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==Notes== | ==Notes== | ||
<references/> | <references/> | ||
Latest revision as of 06:25, 21 November 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.
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| Collimator Mont 7515 image by Hans Kerensky (Image rights) |
Notes
Links
- Lens collimation (with particular reference to a Contax-mount 50mm Sonnar), by Mike Elek
- Lens collimation, by Rick Oleson
