i brought a brand new d5300 50mm 1.8g and tamron 18-200 about 10 months ago. everything is fine. the camera and the 2 lens. i borrow a d300 for testing. i put 50mm to d300. everythings fine. it autofocus smoothly. i tested the front botton beside the cap. and all the sudden it doesnt autofocus. i put it back to my d5300 and also doesnt autofocus. i tried the tamron 18-200 to my d5300 and still doesnt focus. what the hell happened? please help me.

  • Going out on a limb here... is the "front button beside the cap" a "depth of field preview" button? If so, look in the front of the lens - is the iris stopped down and possibly stuck there? Most AF systems don't operate well beyond say f/5.6 or f/8 - that's why lenses focus wide open and only close the iris in conjunction with opening the shutter...
    – twalberg
    Dec 7 '17 at 23:17
  • Hi sir thank you for the quick response. Its already 2:28am here and i cant sleep thinking. Yes i google it. This is depth of view button. I remember i hold this button(DOV) and take picture. I check and click the DOV several times. At first the iris closes to very small. After maybe 30 clicks its stuck to its widest aperture. But when i take the lens to the body and click DOV its ok. What should i do. Why also my tamron lens doesnt autofocus to my nikon d5300. Very very wierd. :(
    – Marc
    Dec 7 '17 at 23:33
  • And also when i try to shake the 50mm 1.8g lens there is something inside. A very little shaking
    – Marc
    Dec 7 '17 at 23:36
  • 3
    @Marc This isn't a discussion forum, please don't ping people for responses - instead add your clarifications to your question so they're easy for everyone to find.
    – Philip Kendall
    Dec 8 '17 at 9:31

Interesting question. I bought the 50mm f1.8G a few months back. It went on and off my old D70 with no issues, but on my D810 it felt stiff when turning into the bayonet fitting. The lens release button also felt stiff, and autofocus didn't operate. When I took it off and tried another lens, there was still a problem with autofocus, but when I took that lens off, looked at the mount and contacts, and put it on again it operated as expected.

The cameras and lens seem to be fine ever since and I've also had that lens on a D3200, but now I've read your question I'm wondering whether the 50mm f1.8G mounts or electrical contacts are stiff when new. It's worth checking the electronic contacts on both the camera and the lens to see they're not misaligned or damaged - it looks like I got away with it.

Hope it works out for you.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.