[geoffb]

Hi, I realise it's an old thead, but - I have a K3 with (Crippled) KAF2 mount, I can't find any sensible (and in laymans terms) information about what lenses will fit (and funcion) properly on the K3, I have looked at KAF3 and KAF4 mount lenses (Pentax HD DA 55-300mm F/4.5-6.3 ED PLM WR RE/Sigma 18-300mm DC Macro HSM Contemporary Lens ) and can't determine if either will function properly with the K3 -I have read about the electromagnetic diapragm etc, but still none the wiser. Ditto for a KAF3 mount lens - still in the dark and don't want to spend the money on new lens that is not entirely compatible with the K3
Thanks

[jatrax]

The K-3 has support for all K-mount lenses including those with the KAF4 mount. Support for KAF4 was added with firmware 1.30

---------- Post added 01-07-18 at 02:38 PM ----------

Perhaps this chart will help: The Pentax Camera Lens Compatibility Chart

[geoffb]

Thanks Jatrax, have udated the firmware to 1.30 recently, but was under the impression the issue with new Pentax 55-300 was an electrical contacts issue and not a firmware fix? Also not really certain that the Sigma (with HSM) will function properly with the K3?
All I'm after is a mid priced (good) tele lens (if such a beast exists) - I'm not that concerned with AF as I find I do a better job with manual focus

[jatrax]

Major features subsequently added through firmware updates:

• Version 1.30: Support for lenses with KAF4 mount, i.e. lenses that have foregone the mechanical stop-down lever
• Version 1.20: Support for AF buttons on the barrel of the HD Pentax-D FA 150-450mm lens
• Version 1.10: Diffraction Correction
• Version 1.03: Support for HD Pentax-DA Rear Converter 1.4X AW
• Version 1.02: AA Filter Bracketing

Issue is not with auto focus but with the lack of support for a mechanical stop down lever on PLM lenses. As I understand it. Not sure what else to say. I have no Sigma lenses but as far as I know HSM has worked on all cameras back to K10D.

---------- Post added 01-07-18 at 03:11 PM ----------

All I'm after is a mid priced (good) tele lens (if such a beast exists)

For consumer lenses the DA 55-300 is about as good as it gets in K-mount. The newer PLM version is faster focusing but either of the older versions will work just fine, especially if you use manual focus anyway. In fact if you are going to use manual focus then there is IMHO no reason to get the more expensive PLM version anyway.

The next step up would be the DA*60-250 which is in another class for size, weight, price and quality.

[geoffb]

Thanks again Jatrax - very helpful info
Impossible to get the earlier the DA 55-300 in Australia (where I hail from), may have to shop in the US for one?

[rr1736]

My Sigma lenses with HSM work fine on my K3

[jatrax]

Impossible to get the earlier the DA 55-300 in Australia (where I hail from), may have to shop in the US for one?

There are a few on ebay.au if you want to go that route. Perhaps some of our Australian members will chime in with a local source for you. But if the PLM version is available that is fine. I just thought the earlier versions might be more cost effective, but maybe not.

[Adam]

Thanks Jatrax, have udated the firmware to 1.30 recently, but was under the impression the issue with new Pentax 55-300 was an electrical contacts issue and not a firmware fix? Also not really certain that the Sigma (with HSM) will function properly with the K3?
All I'm after is a mid priced (good) tele lens (if such a beast exists) - I'm not that concerned with AF as I find I do a better job with manual focus

KAF4 is purely firmware, because the camera needs to be able to tell the lens to set the aperture electronically instead of via the lever. The contacts are the same as on KAF2/KAF3 lenses.

See here for more info:

The Evolution of the Pentax K-mount - Articles and Tips | PentaxForums.com