Sigma 50-500 4-6.3 APO DG won't work with K3

zippity_doodah · 03-01-2021, 04:45 PM

I have a Sigma 50-500 4-6.3 APO DG lens (the "Bigma") that worked beautifully with my K10D that won't work with my K3.

The lens mounts to the K3 as one would expect, feels/sounds perfect as it clicks into place, but it doesn't seem like the lens is communicating with the camera. I get nothing in the viewfinder except a flashing "F--" at the bottom, as if there's no information about the aperture (or anything else) coming from the lens.

I have no idea what's going on here. Any ideas? Thanks folks!

**Bob 256** · 03-01-2021, 04:53 PM

Make sure the lens aperture is clicked into the "Auto" position (A with a little jogged line) on the aperture ring. I have the same lens (older model) and use it with my K-1 with no issues, so it should work with the K3 unless it's something particular to the K3 or contact problems as you mentioned. If the aperture isn't in the auto mode, the lens will choose the aperture making it an aperture priority shot which might disagree with what the camera expects, hence the flashing F.

**jatrax** · 03-01-2021, 05:07 PM - **1 Like**

Flashing F means the camera cannot detect a lens. That is either because the lens is fully manual, is an "A" type lens but not in the "A" position or the contacts are dirty.

Verify that the lens is in the "A" position, if that does not help try cleaning the contacts on both lens and camera. Usually buffing with a microfiber cloth is enough, but alcohol can be used sparingly if absolutely needed.

**ramseybuckeye** · 03-01-2021, 05:08 PM

If that does not work clean the contacts of the lens and the camera (microfibre cloth with a drop of alcohol works well), there could be just a little dirt blocking a connection between the two. Hopefully that's all it needs.

Third party lenses are apparently reverse engineered, and sometimes even it though if it is too far one way on the specs you can have this happen. It's not too common though I have experienced it. I once bought a new Tamron lens that worked with one camera but not another, I had to send it to Tamron twice to get it adjusted, second time with the camera.

zippity_doodah · 03-01-2021, 05:40 PM - **1 Like**

Wow, thanks everyone...I will try the advice and report back!

zippity_doodah · 03-01-2021, 07:50 PM

Thanks again everyone! I have no idea how the aperture ring got bumped off of auto, but that was the problem. I feel a bit dopey that I didn't figure that out on my own, but sometimes it takes a village!

03-01-2021, 04:45 PM	#1
zippity_doodah New Member Join Date: Mar 2021 Posts: 3	Sigma 50-500 4-6.3 APO DG won't work with K3 I have a Sigma 50-500 4-6.3 APO DG lens (the "Bigma") that worked beautifully with my K10D that won't work with my K3. The lens mounts to the K3 as one would expect, feels/sounds perfect as it clicks into place, but it doesn't seem like the lens is communicating with the camera. I get nothing in the viewfinder except a flashing "F--" at the bottom, as if there's no information about the aperture (or anything else) coming from the lens. I have no idea what's going on here. Any ideas? Thanks folks!

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03-01-2021, 04:53 PM	#2
Bob 256 Site Supporter Join Date: Jun 2008 Location: Idaho Photos: Gallery Posts: 2,378	Make sure the lens aperture is clicked into the "Auto" position (A with a little jogged line) on the aperture ring. I have the same lens (older model) and use it with my K-1 with no issues, so it should work with the K3 unless it's something particular to the K3 or contact problems as you mentioned. If the aperture isn't in the auto mode, the lens will choose the aperture making it an aperture priority shot which might disagree with what the camera expects, hence the flashing F.

03-01-2021, 05:07 PM - 1 Like	#3
jatrax Site Supporter Join Date: May 2010 Location: Washington Cascades Photos: Gallery \| Albums Posts: 12,991	Flashing F means the camera cannot detect a lens. That is either because the lens is fully manual, is an "A" type lens but not in the "A" position or the contacts are dirty. Verify that the lens is in the "A" position, if that does not help try cleaning the contacts on both lens and camera. Usually buffing with a microfiber cloth is enough, but alcohol can be used sparingly if absolutely needed.

03-01-2021, 05:08 PM	#4
ramseybuckeye Site Supporter Join Date: Apr 2009 Location: Hampstead, NC Photos: Gallery Posts: 17,295	If that does not work clean the contacts of the lens and the camera (microfibre cloth with a drop of alcohol works well), there could be just a little dirt blocking a connection between the two. Hopefully that's all it needs. Third party lenses are apparently reverse engineered, and sometimes even it though if it is too far one way on the specs you can have this happen. It's not too common though I have experienced it. I once bought a new Tamron lens that worked with one camera but not another, I had to send it to Tamron twice to get it adjusted, second time with the camera.

03-01-2021, 05:40 PM - 1 Like	#5
zippity_doodah New Member Join Date: Mar 2021 Posts: 3 Original Poster	Wow, thanks everyone...I will try the advice and report back!

03-01-2021, 07:50 PM	#6
zippity_doodah New Member Join Date: Mar 2021 Posts: 3 Original Poster	Thanks again everyone! I have no idea how the aperture ring got bumped off of auto, but that was the problem. I feel a bit dopey that I didn't figure that out on my own, but sometimes it takes a village!