DS auto focus problems

rangitata · 02-20-2007, 09:09 PM

I use a DS model with a 50-500mm sigma and other smaller lenses. My problem is that the auto focus function of the camera has stopped working. The motor is whinging but not engaging the lens, both focus select switchs are in the correct position. With my other lens that don't have the a switch on the lens i get no af fuction either. Manual focus still functions perfectly.

Any Thoughts, Cheers

Alvin · 02-20-2007, 10:09 PM

Hi Rangitata,

I think you could have worn parts that need servicing. Even though you hear the motor whine, the focus screw itself may not be engaging the lens properly, or the screw may not be rotating even though it is engaged.

FotoPete · 02-20-2007, 10:29 PM

Yea that might be it. Take the lens off and then switch the camera into AF mode. Check to see if the AF screw head actially extends above the K Mount plate surface. It might be still turning but not extending enough to actually turn the receptor on the lens.

You should get it checked out at the store perhaps.

RiceHigh · 02-21-2007, 12:53 AM

Originally posted by rangitata

I use a DS model with a 50-500mm sigma and other smaller lenses. My problem is that the auto focus function of the camera has stopped working. The motor is whinging but not engaging the lens, both focus select switchs are in the correct position. With my other lens that don't have the a switch on the lens i get no af fuction either. Manual focus still functions perfectly.

Any Thoughts, Cheers

Sound like the body's AF coupler does not engage properly to the lens's coupler, owing to the inaccuracy and large play of the lens mount. Try turning the lens clockwise and anti-clockwise to see if those couplers can in touch and comes into the place!

02-20-2007, 09:09 PM	#1
rangitata Inactive Account Join Date: Oct 2006 Posts: 4	DS auto focus problems I use a DS model with a 50-500mm sigma and other smaller lenses. My problem is that the auto focus function of the camera has stopped working. The motor is whinging but not engaging the lens, both focus select switchs are in the correct position. With my other lens that don't have the a switch on the lens i get no af fuction either. Manual focus still functions perfectly. Any Thoughts, Cheers

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02-20-2007, 10:09 PM	#2
Alvin Veteran Member Join Date: Dec 2006 Location: Mississauga, Ontario, Canada Photos: Gallery Posts: 2,517	Hi Rangitata, I think you could have worn parts that need servicing. Even though you hear the motor whine, the focus screw itself may not be engaging the lens properly, or the screw may not be rotating even though it is engaged.

02-20-2007, 10:29 PM	#3
FotoPete Veteran Member Join Date: Feb 2007 Location: Toronto Photos: Gallery Posts: 1,774	Yea that might be it. Take the lens off and then switch the camera into AF mode. Check to see if the AF screw head actially extends above the K Mount plate surface. It might be still turning but not extending enough to actually turn the receptor on the lens. You should get it checked out at the store perhaps.

02-21-2007, 12:53 AM	#4
RiceHigh Veteran Member Join Date: Nov 2006 Location: Hong Kong Posts: 1,934	Originally posted by rangitata I use a DS model with a 50-500mm sigma and other smaller lenses. My problem is that the auto focus function of the camera has stopped working. The motor is whinging but not engaging the lens, both focus select switchs are in the correct position. With my other lens that don't have the a switch on the lens i get no af fuction either. Manual focus still functions perfectly. Any Thoughts, Cheers Sound like the body's AF coupler does not engage properly to the lens's coupler, owing to the inaccuracy and large play of the lens mount. Try turning the lens clockwise and anti-clockwise to see if those couplers can in touch and comes into the place!