I think a few things should be noted. Nikon cameras also use aperture toggles for reverse compatibility and sigma often used these toggles in their own lens. The toggle answer is a red herring, but it is kind of a problem for pentax since going forward Nikon and Canon both support electronic aperture. The KAF4 mount is a good solution to this problem. From what I have been told it would be a matter of upgrading firmware to make the new mount work. I don't think anything phyical is different. Otherwise there would be wild speculation about an extra pin or something in the K-3 IIs and K-1 mounts. So obviously they are physically the same. That means support for the K-3 has basically already ended. A camera that Ricoh is still selling as new. Not really great if you ask me.
Now back to Sigma: when pressed further about the lenses Sigma eventually admitted that the problem is that there just isn't enough demand to stock their whole lineup in kmount. It seems they will bring over the lenses they think might have the biggest chance of selling, like the 18-35 for instance. Hopefully this will make it really simple for sigma to offer a mount swap option for their lenses going forward since it wouldn't be much different than EOS mount in terms of features now. Also the flange distance is almost identical to nikon further simplifying things. I can see this happening. People should get a campaign together to get sigma to at least offer a kmount swap for all of their art lenses via the global vision program. You would pay a little more, but I think that certainly beats having no Sigma option at all. Pentax would benefit in the long run too. K-1 users definitely could use more choices when it comes to modern FF lenses with silent motors. I would love to see this happen. On Wed, Jun 15, 2016 at 1:18 PM, Mark C <[email protected]> wrote: > FWIW - my SIgma 70-200 f2.8 reports simply "SIgma Lens" in the exif "lens > info" and "lens model" fields as shown on flickr. The Tokina ATX 400mm f5.6 > displays SMC F 35-70 f3.5-4.5 in these fields, but the focal lens is > recorded as 400mm. By contrast genuine Pentax lenses show the specific model > number. > > On 6/14/2016 4:28 PM, Igor PDML-StR wrote: >> >> >> I remember hearing the legend that in era of film SLRs, Sigma did not >> purchase the information on the K-mounts AF interface from Pentax and was >> reverse-engineering it for the purpose of their (Sigma's) K-mount lenses. >> I don't know if that was fully correct or an urban legend. >> I am guessing you, Alex, might be referring to that here. > > > > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
