IS series tele-extenders..., et al.

[beegee675]

Anyone use the Oly IS series of tele-extenders (49mm end attachment) with OM MF lenses? I read that they're better in some cases that the extension tubes... I have some Camedia ones that I tried, but these add-on lenses only seem to work in the longest focal length because of vignetting in the shorter...

BG

 

[thuggins]

The IS series T-CONs are completely different from extension tubes. Extension tubes are hollow (no glass) and are used for close-up/macro photography. A lens will not focus at infinity when using extension tubes.

The T-CONs increase the focal length of the lens. These were required as the the IS lens could not be changed out. So a 1.5x T-CON (the A-200 with the 49mm threads) threaded onto the front of the IS1000 extended the 135mm lens to 200mm. Adding it to the Zuiko 200f5 turns it into a 300mm lens. But the beauty is that the lens is still an f5 (or pretty close). The T-CONs manage this because they have a larger objective than the original lens. So while a traditional 1.4x teleconvertor that fits behind the lens slows the lens by one stop the T-CON A-200 achieves slightly more magnification with no loss of lens speed.

And yes, they work great. The optical quality is first rate and and a single T-CON basically doubles the number of focal lengths you can carry. IIRC the A-200 can be used with a 50mm lens w/o vignetting.

 

[beegee675]

That's what I thought, too. I have a couple of c5060/7070 extenders and they put a real spin on the older MFs with out slowing up the apertures...

 

[beegee675]

With the top of the line IS series cameras going for cheap prices these days, getting a kit with the add-on extenders was a neat possibility to experiment with both cameras and lenses. The IS series is supposed to have great optics, but the encasement of the camera/lens as well as the durability almost delegates it to the collector's area. With the A-200 having the 49mm mount, I would be able to try it on all the MF lenses. Big piece of glass on the end, though.

 

[darinwc]

I have the A-200. It is in a plastic barrel, but I am pretty sure the elements are glass, and they are coated. Being plastic, its not as heavy as you would expect. So it does not add that much weight onto the end.
it does add quite a bit of CA and it flares easily. I would not recommend shooting wide open with it, but one stop down helps alot with the CA. The end result is not quite as sharp, but not bad. Certainly usable in my opinion.