4 comments
Comment from: kruno Visitor
Comment from: mcc Member
The 1.7x AF adapter is not in production anymore, but they do show up from time to time on ebay and other venues. With a little luck you should be able to find one, though it might take a while for one to turn up.
As nice as the 1.7x is with a telephoto, it really shines with a fast 50mm.
Good luck!
Comment from: JC Visitor
Hello Mark
I found your post extremely interesting because I also have a K10D and a 1.7X AF teleconverter. I was planning to find a A* 400 f/2.8 with the idea to transform it into a 680mm f/4.8 but unfortunately I found this page :
http://greenfield.fortunecity.com/deercreek/733/big1/
They mention a possible incompatibility of this lens with the 1.7X AF teleconverter. Your testimony seems to prove the contrary. Can you confirm the association of both gives correct results ?
This point is critical for birding :-)
BTW, you have wonderful bird shots on your homepage
JC
Comment from: mcc Member
Hi JC:
I’m glad I took my bird shots before reading that! I’ve seen no incompatibility between the AF1.7x converter and the 400mm f2.8. The 1.7x adapter needs a fairly fast lens to work with, and f 2.8 is fine with it. The shots in this post and most of the shots in my birds gallery were shot with that combo, and it works fine. In fact, the out of focus areas (bokeh) in shots with the 1.7x are much nicer than with the 2x-l converter.
The AF1.7x converter can only cover a short distance with fast telephotos, so in essence you have to pre-focus manually and then the converter gives you the last ‘snap’ of focus. So, it’s not like using a real AF lens – but you will get that with increasing degrees with any longer focal length lens. (The longer the lens, the shorter the zone that the converter can focus in.)
HTH – MCC
where you buy pentax 1.7 af tc ?
i cant find that anywhere