Results 1 to 3 of 3

Thread: 25mm Extension Tube or Tube Set?

  1. #1
    Join Date
    May 2003

    Default 25mm Extension Tube or Tube Set?

    Hi all,

    I intend to get a extension tube for my 70-300 APO Macro, the problem is i am undecided on which to get: the 25mm alone or the tube set (12/20/36mm). From what i see is that the tube set will offer more flexibility but will cost much more than the 25mm alone.

    The qns is would 25mm alone be enough for macro shots like insects and flowers ? or it is advisable to spend more to get the tube set and get all areas covered.

    Thanks in advance!


  2. #2

    Default 25mm Extension Tube or Tube Set?

    Ya, I also want to know.

    Anyone use it with the APO 70-300 mm before?
    Appreciate your comments..

  3. #3


    I wouldn't waste any time or money on extension tubes for the 70-300mm APO. Extension tubes are best used with lenses with focal ranges between 35 - 105 and are most commonly used with 50mm lenses.

    Stacking a set of three with a 50mm lens will give you 1.47:1 (1.47X life size) macros. Stacking all of them on the 70-300 APO however isn't going to give you a super-duper macro. The reason for this is that the multiplier effect of the extension tubes decrease as the focal length increases, so you'd be better off just using the 70-300 APO's 1:2 macro. If you must use the tubes, then try limiting yourself to the 70-105 range of the lens.

    Teleconverters on the other hand can help increase the working distance for the 1:2 and enable you to do 1:1 at the original distance for 1:2 (0.9m?), but I'm not sure which ones are compatible with the 70-300 APO.
    Last edited by deadpixel; 15th November 2004 at 03:23 PM.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts