[mkawada]

I just got myself got this Tamron telephoto lens. I was extremely excited to use it with the K-01. The first AF shots I took at home at objects within 20 feet were sharp, even at 200mm at F2.8. Of course, MF shots were sharp as well.

Then I tried taking a photo of objects in the distance, like a building down the road or 1/4 or 1/2 mile away. In daylight and AF mode, it's out of focus. No problem, I'll just put it in MF mode. Same results! It's sharp on the LCD screen but once I click the shutter, the image is out of focus. I even put the camera on a tripod and set it to 2-second timer to make sure it wasn't blur from shake. Same result!! Camera is obviously on release priority.

Any idea what the problem is? I didn't notice any problems w/ my 16-50mm F2.8 on the K-01. Nor does this problem exist with my K-X and the Tamron.

[mikeSF]

can you share the pics so we can help diagnose it for you? thanks!

[kiwi_jono]

Its very common for the Tamron 70-200 f2.8 not to work with live view (mine is one of them - but you will see plenty of others on the Tamron user reviews and from googling) but otherwise work perfectly with PD autofocus.

Problem is the K-01 only has live view autofocus, so you might be stuck there without contacting Tamron support.

[Spodeworld]

Is it a screw-drive lens? I've had problems with a screw drive Sigma 17-70. It focused perfectly on all my pentaxes except the K-01, where it always seemed to misfocus. When I put on the Sigma 17-70 with an internal motor on my K-01, it worked fine. I think the camera is temperamental with screw-drive lenses.

[Na Horuk]

I don't have that lens, but here are my recommendations:
a) Make sure you have latest firmware update on K-01
b) Make sure the Tamron lens even allows focus to infinity. Sometimes a lens might have a problem with miscalibrated focusing mechanism, and this can prevent the lens from focusing to infinity.
c) Read reviews of this lens and look for Focus shift or other problems. Some lenses have Focus shift, which means that the focus changes when the aperture stops down. This can be a big problem, because you usually focus with aperture wide open and stop down only for the photo
d) Check the lens for decentering problems. These can become more apparent at certain zoom and focus distance
e) Post some sample photos here, so we can see what is happening

[mkawada]

Resurrecting this thread from the dead.

So about a year ago, I sold this lens to a buyer with a DSLR instead of the K-01 mirrorless, assuming it was my K-01 camera that was causing the focusing issues. The buyer ended up having similar issues, so I refunded him. The lens has been sitting here since. I don't know whether to 1) sell at a big discount or 2) have it repaired. Any idea how much this could cost to repair?

[mkawada]

Update: the former buyer reported back focusing issues with both a K-1 and K-70 that was not adjustable via in-camera settings.

[pentaxfall]

Send it to Tamron for calibration. I do not see any other solution. If you have the receipt they may do it free of charge. Go through Tamron website. Repair center is in Long Island, NY.

[mkawada]

Thanks! I will be sending it to Tamron. It seems like they send you a quote once they look it over. Sure hope it's reasonable. It'll be up for sale, once calibrated/repaired.