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Old 04-09-11, 02:45 PM
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jet_kit jet_kit is offline
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Quote:
Originally Posted by silversnapper1 View Post
I think that jetkit may mean calibration.
No, don't think so.

Collimation is the process of aligning the elements of a complex lens to ensure proper focus at the focal plane. It's not the sort of thing you do in your shed, but lens manufacturers/repairers will have the gear to do it.

Polarmagnus.
What you need is to draw some fine lines on a piece of card about 1mm apart over a distance of about 150mm (Yup, that's a lot of them). Make the centre line thicker than the rest and that's your point of focus. Set the card up at 45 degrees (so the bottom of the card is closest to you and the top furthest away) and focus on the centre line as close-up as the lens will allow at max aperture. Load the image onto your computer and look at it @ 100%. If the lens is correctly collimated the centre line will be sharp and this sharpness will tail off in front and behind that spot. If it's out, the point of maximum sharpness will be elsewhere and you can use that image to show the shop.
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