300 2.8 VR and extension tubes

Discussion in 'Lens Lust' started by roemer, Jul 18, 2008.

  1. roemer

    roemer

    23
    Apr 3, 2008
    netherlands
    I finally convinced myself (after reading a zillion reviews and forum threads) to replace my afs 300 mm f 4 with the 300 mm vr 2.8. I believe that this lens will solve the problems I have with the f4 (focushunting/iq degradation with the tc 1.7 in less than perfect light and no VR). I even found a webshop who has this optical gem in stock and I am ready to spent some serious bucks to (albeit temporarily) remedy this severe bout of NAS.

    But a final question remains: I also use the f4 with the pn 11 for close up on a tripod. I already know that the vr (being a G-lens) will not work with
    the nikon tube (correct me if I am wrong). But what about the combination VR and Kenko? Are there members on this forum who have experience
    with this combination (is it handholdable) and what about the comparison with the f4/pn11. (IQ and ratio)

    With other words: can I also say goodbye to the afs f4 in this department (and sell it).


    greetings

    rombout
     
  2. gvk

    gvk

    388
    Jun 17, 2005
    Mystic, CT
    I have occasionally used the 300 mm f/2.8 VR with Kenko extension tubes. You are correct that there will be no aperture control if this, or any G type, lens is used with the Nikon tubes. Metering, AF and VR all work normally with the Kenko tubes.

    At closest focus of 2.2 m the 300 VR alone provides magnification of about 1:6.1. The maximum magnification is 1:4.3 and 1:3.4 with the Kenko 20 mm and 36 mm extension tubes, respectively. Combining both the 20 mm and 36 mm Kenko tubes results in a maximum magnification of about 1:2.7, giving a field width approximately 100 mm on an FX sensor or 67 mm on DX at a distance of about 1.4 m. I don't find the Kenko tubes stable enough to stack more than two at a time.

    Using the TC14E or TC17E with this lens is another way to achieve higher magnification without much, if any, quality loss particulary since you usually have to stop down a bit to achieve any useful DOF. Combining TCs with extension tubes could provide even higher magnification, but I have not yet had an opportunity to try.

    A nearly 3 kg lens is very difficult to hand hold at even moderate magnifications. For example, angular magnification at 1:3 with the 300 VR is more than 1.5X higher in comparison to the 105 mm VR Micro at 1:1. I have been more successful using a monopod with the 300 mm VR for chasing butterflies or other small creatures.

    As an aside, plotting magnification versus added extension length and taking the reciprocal of the slope provides a measure of the focal length at minimum distance. The result shows that internal focusing reduces focal length of this lens almost 15% to about 267 mm at closest focus.
     
  3. Randy

    Randy

    May 11, 2006
    you will love the 300/2.8 and you will miss the 300/4
    i kept my 300/4 after getting the 2.8
     
  4. Ditto. Me too.