[geoffw]

Hi all. Does anybody know why my K5 won't stop down my old extention tubes? Using an old 50mm f2 lens. The lens alone is ok. Plus the tubes work ok on a K200d. Any thought welcome. Thanks.

[MSL]

It would help if you specified which set of tubes or showed pictures, but I'm guessing they are painted black and this is preventing electrical contact from being made with the body. This is a topic that comes up here pretty often. See, for example,

https://www.pentaxforums.com/forums/115-pentax-k-5/138150-auto-extension-tube...ing-k-5-a.html

[geoffw]

It would help if you specified which set of tubes or showed pictures, but I'm guessing they are painted black and this is preventing electrical contact from being made with the body. This is a topic that comes up here pretty often. See, for example,

https://www.pentaxforums.com/forums/115-pentax-k-5/138150-auto-extension-tube...ing-k-5-a.html

Yeah sorry. Didn't think about which tubes. Despite that, you're bang on the money. They're painted black. So reading between the lines, I'm to get a compatible set of tubes. Thanks MSL

[Stone G.]

So reading between the lines, I'm to get a compatible set of tubes. Thanks MSL

Not necessarily. Like most of us who have encountered that problem, you may sand off the black paint where the tube meets the electrical contacts on your K-5 body. In all likelihood it is black anodizing, rather than simple paint, and coarse grade sand paper ofr a dremel of some sort will be required.

And one word of warning: Other tubes, like my Soligor set, may look metallic, but they are anodized nonetheless - just not black.

[MSL]

Yeah sorry. Didn't think about which tubes. Despite that, you're bang on the money. They're painted black. So reading between the lines, I'm to get a compatible set of tubes. Thanks MSL

nope, just scrape the paint of the right region and it will work just fine. Either use a lens with contacts (A or F type) to show which region needs sanding, or look here https://www.pentaxforums.com/forums/120-general-technical-troubleshooting/217...ure-tubes.html

[elliott]

You can remove anodizing with oven cleaner. Since you have 3 of them to do that might be the easiest way. Remove the mounts, put them in a plastic container with a lid, spray them well and add a little hot water.

[geoffw]

Thanks for all comments. Did as suggested, rubbed off the black, gave a good blast with some canned air to get rid of any fine dust, and it works a treat. Kind regards to all.