this particular tamron (pz-af mc4) has a fairly good reputation. i guess i will know.
as for good extension tubes in pk-af, if you don't mind chinese and if you don't mind aliexpress you can try these: 25mm AF extension tube, costs about $40: https://www.aliexpress.com/item/KOOKA-KK-P25-AF-25mm-Extension-tube-Set-for-Pentax-DSLR-and-K-01-Cameras/32508938916.html?spm=a2g0s.8937460.0.0.41422e0eKUZbFV shortened url: https://bit.ly/2MneVW0 or a set 20/36mm of the same brand tubes: https://bit.ly/2BiQLGZ they get good reports here...ymmv subash On Thu, 16 Aug 2018 13:45:16 -0400 John <jsessoms...@nc.rr.com> wrote: > Tele-converters are not all created equal. I have a Tamron 1.4x > that's garbage and a Sigma 1.4x that's pretty good. The Tamron I have > may just be a bad example, so don't take that as a blanket > condemnation of the brand (although the one Tamron zoom lens I own is > also garbage). > > I've noticed the Sigma TC seems to give better results when paired > with a Sigma lens; and I get better results with Primes than I get > with Zooms. > > That said, TCs can give good results with zoom lenses, just not as > good as they give with primes. I think the TC just magnifies any > defects the lens might exhibit and sometimes those defects aren't > apparent without the TC. > > Slightly OT ... Does anyone make a GOOD, affordable set of extension > tubes in Pk-AF mount? > > > On 8/15/2018 23:02, Subash Jeyan wrote: > > i'm going on a winter trek to the himalayas in november. planning > > to do some birding also along the way and since the sigma 150-500, > > at almost 2kg, is too heavy for that i was looking at alternatives. > > > > i have a tamron 1.4x pz-af (af works with sdm too) and i was > > wondering if i could use that with the da 55-300. i did some > > googling and the results surprised me. it looks, in spite of all > > the conventional wisdom that TCs can only be used with a sharp > > prime lens, people have got good results. see the (old) thread here: > > https://www.dpreview.com/forums/thread/3680410 > > > > have any of you used 55-300, or any other zoom, with a tc? if so > > i'll be interested in how that went... > > > > thanks, subash -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
