7d + sigma 17-50 2.8 - Auto Focus not working in manual mode

[arindam_biswas3]

I bought a new Sigma 17-50 2.8. for 7D,
While in Auto Mode & Creative Auto Mode - The autofocus works fine while the auto focus on the lens is turned on.

Issue - While the camera is switched to manual mode, the auto focus on the lens does not work inspite of the lens' auto focus being switched on.
Camera is reset to factory settings.
Can anyone suggest if it is a defect in the lens or camera or firmware or settings.

Will be grateful. Need to decide whether to return the lens or keep it.

[Waddizzle]

I think you may have more of a problem with your Sigma lens than with your Canon camera body.

Make sure your camera's auto focus mode is One Shot, not AI SERVO.  If it still doesn't work, then contact Sigma.  Even better, get a refund for the lens and buy the Canon version.

[ebiggs1]

"... the camera is switched to manual mode, the auto focus on the lens does not work..."

I believe this is the way the Siggy works.  Because FTM (Full Time Manual) focusing is not a feature in this Siggy.  Also, the focus ring turns during AF.   This lens is not a stellar AF performer.  It has focusing internal, meaning the front element does not extend or rotate.

[Waddizzle]

---

@ebiggs1 wrote:

"... the camera is switched to manual mode, the auto focus on the lens does not work..."

I believe this is the way the Siggy works.  Because FTM (Full Time Manual) focusing is not a feature in this Siggy.  Also, the focus ring turns during AF.   This lens is not a stellar AF performer.  It has focusing internal, meaning the front element does not extend or rotate.

---

That is rather curious behavior for a lens that seems to have the equivalent of an AF/MF switch.  I like internal focusing.

[ebiggs1]

Send the lens back if you can't live with that shortcoming and buy the Sigma 18-35mm f/1.8 DC HSM Art Lens for Canon.  A fantastic lens!

[TTMartin]

---

@arindam_biswas3 wrote:

I bought a new Sigma 17-50 2.8. for 7D,
While in Auto Mode & Creative Auto Mode - The autofocus works fine while the auto focus on the lens is turned on.

Issue - While the camera is switched to manual mode, the auto focus on the lens does not work inspite of the lens' auto focus being switched on.
Camera is reset to factory settings.
Can anyone suggest if it is a defect in the lens or camera or firmware or settings.

Will be grateful. Need to decide whether to return the lens or keep it.

---

Most likely you have moved focus off of the shutter button.

Keep in mind there are up to 4 or 5 different places you need to 'reset' the camera to take it back to factory settings.

Is it a classic 7D or the 7D Mk II.

If it is the classic 7D all you should have to do is reset the Custom Functions, if it is the Mk II there is a place to reset the control buttons. 

The Sigma 17-50 f/2.8 OS HSM is a great lens. Image quality matches the revered Canon 17-55 f/2.8 IS.