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Thread: Close up filters

  1. #1
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    Default Close up filters

    How does the above works? Is it useful? What are the pros n cons?

  2. #2

    Default Re: Close up filters

    Originally posted by currahee
    How does the above works? Is it useful? What are the pros n cons?
    The filter is mounted infront of your cam lens to provide additional magnification. They come in an assortment of +1, +2, +3, +4, +10.

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    so wat magnification is recommended? is there any techniques to be used when using such filters to take close-up shots?

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    Default

    Originally posted by currahee
    so wat magnification is recommended? is there any techniques to be used when using such filters to take close-up shots?
    +4

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    if it's a +4 magnification, so how close can i take a picture if i'm using a 28mm lens, and how closeup is the picture?

  6. #6

    Default

    Originally posted by currahee
    if it's a +4 magnification, so how close can i take a picture if i'm using a 28mm lens, and how closeup is the picture?
    How close depends on how much zoom you have. If you're using a 28mm lens, the magnification will not be too significant. The magnification goes higher with increase in zoom.

  7. #7
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    Default

    it doesn't really magnify but reduces the focussing distance.
    Check out my wildlife pics at www.instagram.com/conrad_nature

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    found some info here: http://www.angelfire.com/ca/erker/closeups.html

    Lens FL refers to the focal length of the camera lens that the close up lens is designed for. Use with a different lens FL may cause sharpness to suffer.
    Diopters are the optical strength of the CU lens. Its focal length can be calculated by using FL = 1000/Diopters. This is also the distance that will now be in focus when the lens is focused at infinity. (A +2 diopter will bring a subject at 1/2 metre {500mm} away into focus.)

    To estimate minimum focus distance convert the camera lens minimum distance to diopters and add it to the CU lens strength. So a +2 CU lens used with a lens that focuses to 1 metre will act (approximately) like a +3 CU lens and bring a subject at 1/3 metre into focus.

    Another approach is to calculate magnification. Convert the diopter strength to millimeters focal length (CU FL = 1000/Diopters). Then divide the camera lens FL by the CU lens FL to get the magnification when the lens is focused at infinity. Thus a +2 CU is 500mm FL. If you use it on a 50mm lens you will get 1:10 life size. The same +2 on a 300mm lens will give you 0.6 of lifesize (1:1.66).
    Check out my wildlife pics at www.instagram.com/conrad_nature

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    more info here: http://www.naturephotobasics.com/page1001.html

    (the pics are not linked properly)
    Check out my wildlife pics at www.instagram.com/conrad_nature

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    Default

    thanx for all the info...
    so closeup lens actually helps to reduce the focussing distance so that u can take closer shots rite?

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    Originally posted by currahee
    thanx for all the info...
    so closeup lens actually helps to reduce the focussing distance so that u can take closer shots rite?
    yup!
    Check out my wildlife pics at www.instagram.com/conrad_nature

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    Default

    it will also make the edges look out of focus rite??

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