[kevingun]

My smc pentax -a 35-105 f3.5 will not focus in the regular focus mode if i push it up for macro mode it works but when i take it out of macro mode the focus ring will turn but it is not focusing like it is not catching or like it is loose or something. Any ideas?

Thanks

[tom1803]

I've repaired quite a few of these lenses.

From your description, it does sound as if something is loose inside.

Did this happen all of a sudden or did you purchase the lens second hand with this problem? If it's the latter, then I suggest that you ask for a refund.

If you want to attempt a repair yourself, then you need to remove the rubber focus grip first to get at the screws to undo the assembly and proceed from there. Be warned, however, that zoom lenses are fairly complex in design and not easy to fix if you have no experience. At the very least, you will need to tighten whichever screws that are loose and adjust for infinity focus. Without actually looking at the lens in hand, it's impossible for me to give you a step by step guide, so I apologise for that.

Good luck!

[kevingun]

Thanks i think i will give it a go and try to fix it