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01-29-2012, 07:19 AM   #1
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Problems with Ext. Tubes

I got a set of of tubes that have the aperture arms can not get them to work with the green button aperture stays wide open when on the camera you can move the arm when off the camera and it opens and closes fine but when you mount it it goes to wide open. What am I doing wrong seems like it would work just like a manual lens.
Trying to use on my K-5

01-29-2012, 08:48 AM   #2
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I assume that you are setting a particular F-stop on the lens using the aperture ring. Can you use the lens properly without the extension tube? Can you stop down the lens by using the DOF setting of the power lever with and without the tube?

Set the lens to a small f-stop like F16 and flip the DOF lever. If the lens does not close down then most likely the aperture arm is not making contact with the camera aperture control. Compare the arm extending from the lens to the one from the tubes and see if they are of different lengths. Also try to dismount and re-mount the tube on the camera.
01-29-2012, 08:58 AM   #3
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Extension tube has a non-metal or black matte non-conductive mount? K-5 won't operate aperture if the pins are not shorted, i.e. if it doesn't recognize that a lens is mounted. Some of the earlier models (K10D, for instance) would activate aperture control with green button even with no lens, but the newer ones will not. If that's the case, you can fix it with a bit of foil tape at the right spot on the extension tube...
01-29-2012, 09:09 AM   #4
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There may be several causes for the problems you are encountering.

From your description of your tubes, I suppose that you have a set without electrical contacts for aperture control?

If so, have you set "Aperture Ring Allowed" in the Custom Settings of your camera? (Menu item C.4.27). And if so,

What lens(es) have you been trying to use your tubes with. It will have to be a lens with an aperture ring and aperture will have to be set manually, (i.e.: if an "A" lens it must not be in the "A" or "AE" position.

If all of that your lens with tune will be at full aperture when mounted on the camera. It will only stop down for the moment(s) you measure the light (green button); when you check the depth of field (using the on-off lever) and when you actually take the picture.

01-29-2012, 09:31 AM   #5
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QuoteOriginally posted by vonBaloney Quote
Extension tube has a non-metal or black matte non-conductive mount? K-5 won't operate aperture if the pins are not shorted, i.e. if it doesn't recognize that a lens is mounted. Some of the earlier models (K10D, for instance) would activate aperture control with green button even with no lens, but the newer ones will not. If that's the case, you can fix it with a bit of foil tape at the right spot on the extension tube...
Right you are!

And the look may be quite deceptive too, as I discovered with my Soligor PK tubes. They look metallic - and they are, but wouldn't work anyway until I realized that the aluminium was oxidized and thus, non-conductive. A piece of sand paper solved that problem:
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01-29-2012, 09:40 AM   #6
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What lens are you using? If you have tubes with no contacts and only the aperture lever, you will need to use a lens with aperture ring. Set the aperture, then use the green button and the meter will set the shutter. It's normal for it to go wide open when mounted, it will stop down for the exposure.
01-29-2012, 10:07 AM   #7
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Yeah, it's the contacts that need to be shorted. I think specifically the one at the bottom of the camera's mount, but perhaps more than just that one. The same thing happens with M lenses that have black anodized mounts, until they're buffed/sanded in the correct position.
01-29-2012, 10:31 AM   #8
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QuoteOriginally posted by Philoslothical Quote
Yeah, it's the contacts that need to be shorted. I think specifically the one at the bottom of the camera's mount, but perhaps more than just that one. The same thing happens with M lenses that have black anodized mounts, until they're buffed/sanded in the correct position.
That was the problem was anodized sanded it down on the tube that mounted to the camera and all is well thanks all for the help.

01-29-2012, 10:49 AM   #9
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This issue seems to come up from time to time and was also an issue with the K7. Maybe we should try a quick survey of which cameras have this issue and make the results a sticky.

For the record this not an issue with *istD or K10D
01-29-2012, 02:53 PM   #10
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QuoteOriginally posted by Lowell Goudge Quote
This issue seems to come up from time to time and was also an issue with the K7. Maybe we should try a quick survey of which cameras have this issue and make the results a sticky.

For the record this not an issue with *istD or K10D
Neither for *ist DL and K200D as far as light metering is concerned.

(For cath-in focus electric conductivity is required, but that's another story).
01-30-2012, 06:54 AM   #11
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I had a similar problem with a teleconverter on my K20, but scraping off the anodized area solved it all
01-31-2012, 01:14 PM   #12
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Summary of Informal Poll

To summarize the results so far, considering the top of the line models Those in Bold Italics require conducting lens mount and contact to the info pin to stop down a lens or teleconverter or extension tube.

*istD, K10D, K20D, K7D, K5D

As for the other models it seems the following are OK based upon K200 being confirmed OK and all other models being earlier,

*istDS, *istDS2, *istDL, *istDL2, K100D, K110D, K100Ds, K200D.

What about K2000, K-x, K-r???
01-31-2012, 01:41 PM   #13
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K-r requires shorting, presumably the K-x does, too. No clue about the K2000.
01-31-2012, 04:44 PM   #14
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It's simple to find out whether your camera body requires the lens contacts being shorted or not.

Turn on the camera with no lens attached. If the camera asks for the focal length, it does not need the lens contacts being shorted.
01-31-2012, 05:14 PM   #15
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QuoteOriginally posted by SOldBear Quote
It's simple to find out whether your camera body requires the lens contacts being shorted or not.

Turn on the camera with no lens attached. If the camera asks for the focal length, it does not need the lens contacts being shorted.
Only if you own one!
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