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12-29-2010, 12:36 PM   #31
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Yusuf: PErhaps the lighting is casting a shadow which makes the guide appear kinked, or bent, but it surely looks to be on my end. The 1st shot below is your shot, with a thin red circle around the area which appears damaged to me:



This second shot, is of my 17-50, from a different angle.




Please post some more shots of your lever and guide--if you get the right angle, minus shadows, this should be easy to settle.

Also, can you please explain exactly what you mean when you say the lens does not work on either body, again, with new words? I would ignore what the LCD says for now. If the pics are overexposed, this does not necessarily mean the aperture is faulty.

12-29-2010, 05:52 PM   #32
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Yusuf:

I will be heading on out of here now--perhaps someone more qualified will help you. I have been on vacation, and had extra time--wish it all worked out.

Good Luck

JT
12-29-2010, 10:27 PM   #33
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QuoteOriginally posted by Jewelltrail Quote
Also, can you please explain exactly what you mean when you say the lens does not work on either body, again, with new words? I would ignore what the LCD says for now. If the pics are overexposed, this does not necessarily mean the aperture is faulty.
This last is why i asked earlier abt doing a stopped down optical or digital preview, and also doing a green button meter reading in M mode.

Basically, if you set in your viewfinder the f-stop value down to f8 or f11 and smaller, then do an optical preview, the camera will physically stop the lens down. --Take the camera out of any program modes and into Av mode first, that'll remove any unnecessary automation from the mix.

If the viewfinder darkens, then it's stopping down to the f-stop you set in the viewfinder, and will mean something works.

If you preset the f-stop to a small opening and do an optical preview and the viewfinder doesn't darken, then the lens isn't stopping down when it should.

The digital preview just takes a photo without saving it, might not amount to anything in terms to giving any indications abt this prob.

Forget what i mentioned earlier abt doing a green button meter reading in M mode. i forgot that only makes sense if the lens has an aperture ring that can be moved off of A into discrete f-stops, and this lens doesn't.

The photos of the back of your lens all look normal to me. My 17-50mm looks the same.

Jewelltrail, you're the man for stepping in and helping yusuf out.
12-30-2010, 06:52 AM   #34
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Sorry for your trouble.

FWIW, the lever on the serviced lens is silver while the lever on the other has a black finish. My 28-75mm has a black finish. Somehow the silver finish looks out of place to me.

I'd measure yours and a known good sample to determine if the silver one is a bit shorter. Who know what body was used to confirm the repair, or if a body was even used to confirm this.

After reading this thread, I am inclined to believe that the lever is just a tad short OR the electronics are gone.

Does "expert repair" mean "Tamron?" Do you have the receipt for the work done? Most repairs are warranted. I'd look into returning this to the depot that did the work.

Hoping that you find a satisfactory resolution to this.

woof!

01-01-2011, 12:14 AM   #35
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Here is new images. I tried to use green button for stop down metering and it does not work either.



01-01-2011, 07:50 PM   #36
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QuoteOriginally posted by yusuf Quote
Here is new images. I tried to use green button for stop down metering and it does not work either.
Still don't see anything wrong with the mount or levers. Looks ok to me.

As i wrote previously, i was wrong abt the stop down metering: that only applies when you're using a lens with an aperture ring, when you're setting the f-stop on it by hand.

On the A setting on the aperture ring, and on lenses without an aperture ring, the camera will forgo physically stopping the lens down when you do a green button manual meter.

But do try an optical preview. On the K-X you'll need to first customize the green button to do optical preview. Then put the camera on Av mode, set the f-stop value in the viewfinder to a small value, f11 say, then do an optical preview and see if the camera will actually stop the lens down. The viewfinder will go dark when the lens is being stopped down. If it doesn't darken, lens isn't stopping down.

Try this with another lens capable of auto aperture.

If the Tamron doesn't stop down while another lens does, you definitely have internal problems with it and it should be sent off for service.

i went and looked over your flickr gallery: very nice portraits. i'm sorry this lens hasn't been working out for you, yusuf.
01-02-2011, 04:17 AM   #37
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Thanks conradj though I rarely update flickr now a days.

Yes. green button is configured fine since I use so many manual lenses. I think A pin on mount might be an issue. It might not indicating it as A lens and hence camera may not be changing it though it contradicts with the fact the aperture indication is getting changed in viewfinder.

I am a bit puzzled now, what role does electronic plays apart from EXIF, indicating A, max & min aperture?
01-02-2011, 06:36 AM   #38
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The k-x treats lenses with the A-pin contact active / not active differently, one thing is displaying F-- for aperture (which makes sense), others are that matrix metering and pttl are not available (which makes less sense. Also, it seems that AWB works differently with an A50 1.7 aperture ring in the A position or not and even exposure might be slightly different (which make even less sense).

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