[Quich]

Hello everyone,

I am posting here after putting my problem in the "Pentax SLR Lens Discussion" section as Scorpio71GR suggested there.
You can read the previous thread: https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/310528-issu...x-1-4x-tc.html

Long story short: using the Pentax HD-DA 1.4x AW TC or closing tightly a rear cap on the mount, the focus ring of my DA* 60-250 does not work as it should and does not move the focus elements.

I recorded the problem:

Youtu.be

Youtu.be

It first appeared to me when shooting and trying to modify the focus point on my K3 with the Pentax 1.4x TC + 60-250.
Then I tried several combinations, and the focus ring works as it should with:
- lens alone without caps or with original caps
- lens mounted on K3
- lens + TC 1.7x promaster
- lens + TC 1.7x mounted on K3

But it was not working when mounting the Pentax 1.4x TC on the lens, the TC itself being attached to a camera or not.
The 1.4x TC is working without problems with my DFA 100mm Macro WR and a DA 50. The focus shaft is rotating as it should.
When using the DA*, the shaft is not used as it is a SDM lens and it is not rotating at the lens nor at the TC (even when not mounted on a camera body), I think it is the expected behavior.

Then, when I wanted to record the problem with the 1.4x TC attached to the lens, it started behaving normally. I had no idea why and I continued to rotate the ring under different situations, to try my other lenses with the Pentax TC, etc.
I discovered by luck (or not ) that the problem was here when using a non Pentax rear cap on the DA* 60-250, and I recorded it in the above video.
It is very strange as no part is moving on the DA* mount and the cap is not opposing anything to anything. As soon as I remove the cap or lose it a little bit, the focus ring starts working again.

The lens seems to work with and without my TC now so I am fine, but I still find that strange and would like to know if anyone has seen something similar in the past.
The lens was bought in a French Fnac in July 2015 (but may have been in stock there for a while), and is still under warranty.

I also have a second question about the aperture blades of the DA* 60-250.
When I manually move the aperture lever on the lens to the max aperture position, I can still see a bit of the aperture blades (at least at 60mm, at longer zoom position they are hidden by other part of the lens) as if they were not completely retracted. On my other lenses it usually does a nice circle or I can not see them and see only the circle due to the lens construction but here it is not exactly the case.
Is it normal for this lens? I tried to show it in the video but I may take a picture tomorrow.

Best!