Cleaning the tamron 17-50mm f2.8

[vaga2681]

Hey anyone of you guys have experience cleaning this tamron lens? I opened it up to clean out the dust inside and I manage to remove the back element, the one which is closest to the camera body. The element is a plastic ring around 2 cm thick with 2 lenses mounted on each side of the plastic ring. The dust particles are in between the 2 lenses. It seems that these lenses are glued on the plastic ring and I can't open them.

Anyone of you have experience opening this element? The dust don't affect the picture quality but it is really an eye sore to see it there all the time. Appreciate if anyone of you can share with me your experience of opening up this lens before. Thanks.

[vaga2681]

The dust is trapped in between 2 lenses. And it seems there is no way of opening one of them without breaking the plastic. These are pictures of the element









If you have opened this lens b4, please share your experience with me.

[fatigue]

If it's sealed there's nothing you can do.

Caution:
1. There's a spring under the contact PCB
2. Return the glass assembly to it's original orientation. The 3 screw mounts are spaced evenly so you can easily rotate the glass 120/240/360 degrees. Since it is made out of plastic,it is possible that there's some tolerance in thickness. That's the reason why there's some washer to correct the alignment.
It might affect alignment if not return to original position.
3. Take note of the washer position.

[geomixz]

U dont need to open it , juz use the blower to blow it at the side blow and blow until u see the dust gone . I try b4 it work .

[fatigue]

Originally Posted by geomixz U dont need to open it , juz use the blower to blow it at the side blow and blow until u see the dust gone . I try b4 it work .

You could be right. If dust could go in, it's not sealed.
Blow and blow until the dust is out.

[calebk]

Sigh...the best advice I can give is ignore the dust and shoot some more beautiful photos. You know very well that it doesn't affect your image quality, so why be itchybackside and open your lens? For all you know, more complications will arise.

[grumpy]

Originally Posted by calebk Sigh...the best advice I can give is ignore the dust and shoot some more beautiful photos. You know very well that it doesn't affect your image quality, so why be itchybackside and open your lens? For all you know, more complications will arise.

Precisely, if it is not affecting picture quality, why take such risk to open it and subject it to other possible contamination?

[vaga2681]

Hey thanks for the reply and the enlightenment. It make sense to me now that the spring washer somehow needs to be calibrated by how much we tighten it. My lens somehow already has some degree of back focus. So may be by tightening it all the way, it may have corrected it. I will try to take some photos and examine the focusing.

[fatigue]

Originally Posted by grumpy Precisely, if it is not affecting picture quality, why take such risk to open it and subject it to other possible contamination?

Too bad, our advise was a bit late. He has opened the lens before he asked for advise.

[calebk]

Originally Posted by fatigue Too bad, our advise was a bit late. He has opened the lens before he asked for advise.

Whoops!