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Photography Question 

Jody A. Toopes
 

How to use a teleconverter lens


I have a Nikon N75 and recently purchased a Kenko 2x teleconverter. I have trouble sometimes getting my camera to A. focus(in auto focus mode) and B. the shutter will not shoot when pressed even with the subject in focus. Any suggestions?


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September 10, 2007

 

Jon Close
  (a) Autofocus will not work reliably if the effective aperture is too small (f-number greater than f/5.6 or f/8). The 2x teleconverter doubles the focal length, but cannot make the lens diaphram larger, so an f/4-5.6 lens on a 2x TC has effective maximum aperture of just f/8-11.

(b) Shutter will not release. What is displayed in the camera's LCD panel and viewfinder? If "F--", then the teleconverter is not communicating the lens aperture to the camera and the shutter release will be inhibited in all exposure modes except M. If "FEE" is displayed, make sure the lens aperture ring is set to the largest f-number.


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September 10, 2007

 

Jody A. Toopes
  OK - on question (b) usually "F--" appears in the viewfinder. I am strictly amateur and therefore have never messed w/ the aperture ring. I would not know where to begin. I use the camera mostly for action sports shots. My lens is a Tamron 70-300mm f/4-5.6. My aperture ring is set as it was when I received it at 32. What would be a good setting? I hope this is making sense as I really have no idea what I am talking about. Thanks - Jody


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September 10, 2007

 

Jon Close
  The N75 is designed to control the lens aperture from the camera, so the lens needs to be set always on the "auto" aperture setting (f/32 for your lens). Even if manually setting the aperture in A or M modes, leave the lens aperture ring set on f/32 and set the aperture you want with the controls on the camera.

The teleconverter should allow the camera to control the lens aperture. That it shows "F--" in the display means that the communication is bad. Either the lens is not fully seated on the TC, the TC mot fully seated on the camera, and/or the electronic contacts in the mounts are dirty and not making a good connection.


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September 10, 2007

 

Jody A. Toopes
  OK-I just remounted the teleconverter to the body of the camera then mounted my lens to the teleconverter and with the lens mount I do believe it seemed to "fit" better. Maybe it was just a bad connection. I will have to try it out next time I have a sporting event. Thanks for you help! Jody


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September 10, 2007

 

Samuel Smith
  welcome jody,
what i'm thinking jody is with your 2x you'll have to double your iso at those sporting events even in good light.
do your self a favor and get down closer to the action and try to avoid the converter.unless of course your getting proficient with manual focus and slowing your lens and shutter speed down.
sam


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September 10, 2007

 
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