Quick question about tele-converters.

kithylin

Hi, I asked something similar in the past, but looking for just a *smidge* more information on this subject.

I recently purchased a "Tamron 55-200mm f/4.0-5.6 DI-II LD AF" lens that i like alot, but I'm considering a tele-converter for just a little more zoom, sometimes, not all the time.

My question is this, do i need to get a Tamron specific teleconverter and contact tamron to figure out which one will work with my new lens, or can i just get a Nikon/Nikkor made one that supports autofocus?

zoomer

No it does not need to be brand specific.
Just make sure it is a nikon mount.

Imagine you are aware you will lose sharpness and possibly autofocus.
Someone more technical than me may jump in and tell you for sure on the autofocus.

Typically tele converters do not work well with consumer grade lenses.

ziggy53

kithylin wrote: »

... My question is this, do i need to get a Tamron specific teleconverter and contact tamron to figure out which one will work with my new lens, or can i just get a Nikon/Nikkor made one that supports autofocus?

You best bet is to contact Tamron directly. With teleconverters there are 3 areas of concern:

1. Physical coupling
   
2. Optical coupling
   
3. Electrical coupling

Some teleconverters protrude at the front and require clearance into the lens. If the lens does not have clearance then the teleconverter will not mount the lens.

Some teleconverters work much better than others in conjunction with certain lenses. As "zoomer" said many consumer telephoto lenses are not designed to use teleconverters at all.

Some teleconverters relay the "compensated" f-setting through the electrical contacts, while others only pass the lens' aperture status back to the camera. Sometimes you can also "tape" a teleconverter to prevent the teleconverter from passing the compensated f-setting. The advantage to only allowing the lens aperture status is that AF may still continue to work. While AF may still work it may not be as reliable or as quick as with the lens alone.

kithylin

Hrmm, thanks for all the input and information. I may try and contact tamron later and see what they say. I had a teleconverter before (just recently sold it) that i used with a push-pull manual zoom manual focus older film lens from Tokina, it wasn't -that bad- for focusing, and in day time in the sunlight it was producing decent shots.

I just wasn't familiar with the new digital lenses and autofocus and how it worked with teleconverters.

And yes i'm aware this new lens i bought is a "consumer lens", but it being made in 2006 is alot more advanced than the 1970's film lenses i have been using, so.... maybe just use it as is and not worry about a teleconverter then, it seems with autofocus + digital lenses that it's alot more headache than it's worth.