teleconverter for nikon d50

Discussion in 'Digital Photography' started by TheMasin9, Apr 1, 2006.

  1. TheMasin9 macrumors 6502a

    TheMasin9

    Joined:
    Dec 22, 2004
    Location:
    Huber Heights, OH
    #1
    was wondering if anyone had any experience with teleconverters good/bad and the pros cons of them.

    Thanks
     
  2. Mr. Jones macrumors member

    Mr. Jones

    Joined:
    Apr 1, 2006
    Location:
    Twin Cities
    #2
    Well, I don't own a Nikon, but the way it works with my Canon equipment is you have the advantage of seeing farther, but you lose 2 f/stops, thus making your your exposure time longer. It's fine for night shots, but not the best for everything else. It also only works on certain lenses as well, so double check compatibility.
     
  3. Clix Pix macrumors demi-goddess

    Clix Pix

    Joined:
    Oct 9, 2005
    Location:
    8 miles from the Apple Store at Tysons (VA)
    #3
    You would choose a teleconverter based on the lens; the camera body doesn't matter here, although of course there does need to be compatibility as well. Some lenses are not compatible with teleconverters, either. Usually they are used with zooms and long telephotos. In Nikon's line there are three basic "sizes" of TCs: 1.4x, 1.7x, 2.0x. The last gives you double the range but costs you in terms of f/stops. This may or may not be a critical issue for you. Certainly purchasing a teleconverter can be an inexpensive way of extending your range without plunking down big bucks for an expensive longer telephoto lens.

    Probably the best thing to do is to take your camera and lens(es) to a full-service camera store and ask to try out the different TCs with your equipment in order to see if this is what would work for you. Since you've got the 70-300, chances are that if you slap a 2.0x TC on it, you are going to lose 2 full f/stops and be very unhappy because that is already a "slow" lens to start. Usually when shooting with something like the 70-200mm VR, which is f/2.8, a faster lens, a teleconverter is more satisfactory.
     
  4. jared_kipe macrumors 68030

    jared_kipe

    Joined:
    Dec 8, 2003
    Location:
    Seattle
    #4
    Kenko Pro AF 300

    1.4x eats 1 stop of light
    2.0x eats 2 stops of light.

    2x usually degrade the quality to the point you don't really want to use one. 1.4x's are better in this respect.

    Here is some side by sides
    http://www.pbase.com/fstopjojo/lenstests (bottom of the thumbnails)
     
  5. Clix Pix macrumors demi-goddess

    Clix Pix

    Joined:
    Oct 9, 2005
    Location:
    8 miles from the Apple Store at Tysons (VA)
    #5

    I'm not that familiar with the Kenko TCs, but that's interesting that their 1.4x "eats 1 stop of light." The 1.4x Nikon TC doesn't, it's more like half a stop or something. The Nikon 1.7 takes a full stop away, though, and the 2x TC takes two full stops away.
     
  6. ChrisA macrumors G4

    Joined:
    Jan 5, 2006
    Location:
    Redondo Beach, California
    #6
    Which TC will work depends on which lens you use. Nikon has made so many of each over the years that you need to phrase this question in terms of a specific lens.

    In general the 1.4 X converters do not degrade the image much but the others degrade it enough that you may as wel just crop. Cropping is the "free" tele-converter option.

    Also in general the 1.4 X TCs are best used with a f/2.8 or faster lens and you can't really use a TC with an f/5.6 lens because you loose autofocus ability and the viewfinder is dark at such low f-stop for god manual focus. But on an f/2.8 lens it works near perfectly
     
  7. ChrisA macrumors G4

    Joined:
    Jan 5, 2006
    Location:
    Redondo Beach, California
    #7
    No it does not work that way.


    The reduction in f-stop is defined by simple geometry. All TCs must work the same because "f-stop" is defined by geometry.

    Here is how to figure it out:

    f-stop is defined as simply the lens focal lenght divided by the efective diameter

    Assume a 200mm f/4 lens. The efective diameter must be 50mm.

    Multiply the lengh by 2x and you get 400mm. So the result is an f/(400/50) or f/8 lens which means two stops

    if you use the 1.4x TC then 200x1.4= 280 and 280/50 = 5.6 which means one stop

    The 1.7x converter will be in between the 2x and 1.4x and it a 1 and a half stop loss.
     

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