New Sigma 17-70mm MACRO 1:2.3

I just get a new Sigma 17-70 MACRO (thanks Ryan) and I was wonder what would happen if I try to get 1:1 of the 1:2.3 this lens have. I know in prime lenses if you add a TC it steal light and a diopter steal distance, but i don´t know how it works in zoom lenses... (or maybe don´t work at all...). Anyone? an extension?

The Kenko 2xTC works with lenses with apertures down to F5.6. The Sigma lens goes down to F4.5 at the long end of the zoom, so you should be able to use autofocus with that lens and a 2x TC.

This setup will give you close to 1:1 reproduction ratio. You can even slap on a Woody's diopter and get slightly more than that!

Cheers,

Mat

FWIW, most teleconverters are made to work with lenses w/ a focal length longer than 100mm. Something to consider.

Cheers

James

I checked in B&H and Kenko TC are not recommended for lenses wider than 50mm, and AF operation is only possible with lenses with f/2.8 or brighter, so i think this can affect the idea....

These recommendations are very conservative, and for some are only "recommendations", e.g. if you use the TC with a wide lens, it will still work. There is no physical or other type of reason why it won't.

As a matter of fact, I've just tried mine with the nikkor 12-24mm F4 at the wide end, in my room, at night with rminimal lighting, and it works well.

I guess in the case of the Sigma 17-70, it's a matter of testing out this particular combination to see if it works.

So, I checked it and i find some Teleconverters in B&H "2X DG AF Teleplus Teleconverter for Nikon", I have a D50, so I wonder if all TC made by Kenko for Nikon fit the camera and the lens?, Of course, what is left is figure if it didn´t bump the port in full lenght...

Some lenses (usually wides) have a rear element that protrudes out the back and can crush the optics of the teleconverter. Something else to look out for.

Cheers

James

I've used my tele with the 10.5 once, it worked without a problem (I know why would you want to do that, I was just seeing if it was possible)

The Teleconverters kenko made for Nikon lenses are the same for Sigma´s Lenses?? So, what exact model of 2X TC i should I get? (maybe a reference on B&H..) Tx.