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Thread: What is the diff btw a Telephoto and a std Zoom lens?

  1. #1
    Senior Member Big Kahuna's Avatar
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    Default What is the diff btw a Telephoto and a std Zoom lens?

    Was checking out some lens info at sigma and saw this.

    http://www.sigmaphoto.com/lenses/lenses_all.asp

    For std zoom lens...the range from 28-300mm

    For Telezoom....it start very far say 70-300mm

    But since both can do 300mm....why the manufacture bother to made two different lens?

    If I want to zoom, which type give me better Ommmph?

  2. #2

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    besides focal length, the other factors to consider are image quality, weight, build , bokeh and aperture.

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    Quote Originally Posted by loupgarou
    besides focal length, the other factors to consider are image quality, weight, build , bokeh and aperture.
    How does we determine and define bokeh?

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    Moderator ortega's Avatar
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    Standard zoom lens are more for people who want to bring only 1 lens to cover everything fromwide angle to telephoto, usually there is a trade off on the image quality.

    Telezoom if you notice is only in the telephoto range and normally better.

    A wide angle and telephoto lens are 2 entirely different monsters.

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    when you want a really good cup of coffee, do you go for 3-in-1 instant mix, or pure freshly brewed?

    zoom lens are like 3-in-1 coffee mix or 3-in-1 shampoos. you might have everything thrown in, but you sacrifice taste and effectiveness .. and in the case of lenses, optical quality, sharpness, speed and the likes.

    the more you try to squeeze a zoom range into a lens, the more likely you get distortion etc.

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    Quote Originally Posted by Stereobox
    when you want a really good cup of coffee, do you go for 3-in-1 instant mix, or pure freshly brewed?

    zoom lens are like 3-in-1 coffee mix or 3-in-1 shampoos. you might have everything thrown in, but you sacrifice taste and effectiveness .. and in the case of lenses, optical quality, sharpness, speed and the likes.

    the more you try to squeeze a zoom range into a lens, the more likely you get distortion etc.
    True, true! That's the reason why I always use prime lenses.
    Each have its own pros and cons also la.

  7. #7

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    Quote Originally Posted by Stereobox
    when you want a really good cup of coffee, do you go for 3-in-1 instant mix, or pure freshly brewed?

    zoom lens are like 3-in-1 coffee mix or 3-in-1 shampoos. you might have everything thrown in, but you sacrifice taste and effectiveness .. and in the case of lenses, optical quality, sharpness, speed and the likes.

    the more you try to squeeze a zoom range into a lens, the more likely you get distortion etc.
    I love your analogy! Mind if I use it in future?

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    Senior Member Big Kahuna's Avatar
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    Quote Originally Posted by Stereobox
    when you want a really good cup of coffee, do you go for 3-in-1 instant mix, or pure freshly brewed?

    zoom lens are like 3-in-1 coffee mix or 3-in-1 shampoos. you might have everything thrown in, but you sacrifice taste and effectiveness .. and in the case of lenses, optical quality, sharpness, speed and the likes.

    the more you try to squeeze a zoom range into a lens, the more likely you get distortion etc.
    Thank you...I like your explaination...very lay man and easy to understand.....so since I already have the kit lens...I guess the Telephoto is more appropriate if I want power

    So what about a teleconvertor....how come such a tiny thing can give you upto 2x the range? For the price isn't it everyone can afford one?

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    Quote Originally Posted by student
    I love your analogy! Mind if I use it in future?
    lol..sure, but it sure didn't first come from me. my mentors used similar analogies to explain, too

  10. #10

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    Quote Originally Posted by Big Kahuna
    Thank you...I like your explaination...very lay man and easy to understand.....so since I already have the kit lens...I guess the Telephoto is more appropriate if I want power

    So what about a teleconvertor....how come such a tiny thing can give you upto 2x the range? For the price isn't it everyone can afford one?
    The Tele-converter (in SLR context) is like a magnifying glass attached at the Rear of a lens and in between the lens and camera.

    It magnify the image by 1.4x or 2.0x (depending on the type u get), but by doing so it also magnify the "hole" (the aperature hole, i mean) by 2x.

    And so u lose 2 stops of light with a 2x TC and 1 stop of light with a 1.4x TC
    (For questions abt f-stops, read up more on the topic of Exposure)

    The key to understanding f-stop progression is the knowledge that each successive f-stop increases logarithmically by the square root of 2 (i.e. 1.4)
    .
    f1.0 f1.4 f2.0 f2.8 f4.0 f5.6 f8.0 f11.0 f16.0 f22.0

    Example: a 70-200mm f/2.8 will become a 140-400mm f/5.6, the aperature also doubles to 5.6


    And thats probably the main disadvantage of using a TC to extend the focal length over buying a similar zoom lens of the same focal length.

    And a TC cannot be used on all lenses, only lenses listed as compatitble can be used on it.

    Sigma TC (for nikon mount) cant be used on Nikkor lenses (even though they are the same mount)
    Similarily a Nikon TC cannot be used on a Sigma lens (even if it is nikon mount)


    and lastly...TC aint cheap. They cost like S$600 or more each.



    some useful links and read-up

    http://www.microsoft.com/windowsxp/u.../exposure.mspx

    http://www.luminous-landscape.com/tu...exposure.shtml
    Last edited by Winston; 4th February 2005 at 06:12 PM.

  11. #11

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    Quote Originally Posted by XXX Boy
    How does we determine and define bokeh?
    bokeh loosely refers to the appearance f the out=of=focus areas in the bacground. its a very subjective interpretation. but in general most agree that doughnut-rings are bad quality bokeh

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    Quote Originally Posted by Stereobox
    when you want a really good cup of coffee, do you go for 3-in-1 instant mix, or pure freshly brewed?

    zoom lens are like 3-in-1 coffee mix or 3-in-1 shampoos. you might have everything thrown in, but you sacrifice taste and effectiveness .. and in the case of lenses, optical quality, sharpness, speed and the likes.

    the more you try to squeeze a zoom range into a lens, the more likely you get distortion etc.
    As for image quality being second rate in a telezooms, it may have been true in the past but and computerised aided design has enabled lens manufacturers to come up with zoom lenses that are almost on par with the prime lenses in terms of image quality.

    I also personally find Sigma lenses to be .

  13. #13

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    Quote Originally Posted by Zenten
    As for image quality being second rate in a telezooms, it may have been true in the past but and computerised aided design has enabled lens manufacturers to come up with zoom lenses that are almost on par with the prime lenses in terms of image quality.

    I also personally find Sigma lenses to be .

    Almost .... but not quite ...... only a few can be really somwhat par .....

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    Quote Originally Posted by blurblock
    Almost .... but not quite ...... only a few can be really somwhat par .....

    Which are the ones that you would recommend?

  15. #15

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    Quote Originally Posted by Zenten
    Which are the ones that you would recommend?
    sigma 70-200/2.8

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