chemdoc Loc: West Coast

I just made the switch from Canon to Nikon and my D750 has an autofocus motor as does my Tamron 24-70 lens. I am wondering if I should leave the camera autofocus on or off when using the autofocus on the lens. And if I want to switch the lens to manual focus do I also need to switch the camera to manual as well? Thanks.

Phil

Nikonian72 Loc: Chico CA

I believe that your camera is designed to defer A-F to the lens. When you switch the lens to M-F, it will then only manual focus, regardless of camera setting.

D750 autofocus system and AFC modes: http://www.funtechtalk.com/how-to-use-the-focusing-system-on-the-nikon-d750-when-to-use-afs-afc-or-afa

lamiaceae Loc: San Luis Obispo County, CA

I believe the mid and higher end Nikon cameras may have AF motors that are used only when using older AF lenses (film), the modern digital Nikon lenses have the AF motor in the lens (like a Canon). Pentax typically does it the other way, with the AF motor in the body. Nikon users can give you model information.

mcveed Loc: Kelowna, British Columbia (between trips)

If you take the lens off of your D750 and look at the lens mount on the camera, you will see a little hole with what looks like a tiny screwdriver head sticking out of it. If you press the lens mounting button on the camera the little screwdriver withdraws into the hole. Lenses without auto focus motors have a matching hole with a little screw head inside. The D750 focusing motor turns the little screw driver which activates the mechanical focusing mechanism in the lens. Lenses with their own focusing motor do not have the little hole with the screw head inside so the screw driver head sticking out of the D750 has no where to go. The camera motor cannot focus the lens so the AF motor in the lens takes over. Mid and higher end Nikons have the focusing motor and can use older lenses which are not AFS lenses. Lower end, consumer grade Nikons do not have a focusing motor and can only use AFS lenses which have their own motor. The camera communicates electronically with AFS lenses to activate the autofocus. If you turn off camera auto focus you will turn off the communication and you will have to manually focus the lens.

Macronaut Loc: Redondo Beach,Ca.

Your camera is smart enough to know if the lens has a motor or not and knows what to do. :wink:

DaveO Loc: Northeast CT

Big deal. My smart TV still has stupid programs.....

bebo1998 Loc: Baltimore MD area

:thumbup:

Mac Loc: Pittsburgh, Philadelphia now Hernando Co. Fl.

:lol: :thumbup: :thumbup: :lol:

Jim Bob

Use the camera controls.

CO

Excellent description. Also, if you have a lens without its own focusing motor and you want to manually focus be sure to put the camera's switch to the MF position. Someone tried to manually focus one of my older cameras once and forcefully turned the focus ring. I thought they were going to break the mechanism. Fortunately, everything is alright with it.

chemdoc Loc: West Coast

One interesting thing I found was if I turn off the camera autofocus while leaving the lens on autofocus, the lens would not autofocus. It seems that I have to leave both on. Seems odd.

Phil

TucsonCoyote Loc: Tucson AZ

:thumbup: :thumbup: :XD:

Jim Bob

That's why I said use the camera controls.

DaveO Loc: Northeast CT

:thumbup: :thumbup: :lol: :lol:

orrie smith Loc: Kansas

your best option, in my opinion, would be to set up your camera to back button focus. that way, when you want to manually focus, you do not need to turn off anything, just manually focus. you could use your back button focus to get close, release the button and fine focus. that way you will not lose focus when releasing the shutter.