Lenses with full-time manual focus.

[quekbc]

I'm using a Canon EOS 7D and have just recently gotten myself a lens with full-time manual focus.

When I tried playing around with the manual focus in AF mode, the camera always overrides my manual adjustment back unless I set my AF-drive to One-Shot.

Is this how it's meant to be used or is there a way to use it other AF-drive modes?

[mattjordan]

I also have a 7D and a lens with full-time manual focus, and I really never had a problem with it. Normally if I have to refocus I keep the shutter pressed halfway, change the focus and then give it a full press. So as long as the lens is in AF mode each time you press the shutter button it will focus.

Hope this helps.

[quekbc]

That's what I did.

Oddly, I depress the shutter button halfway to focus, adjust it, and watch the 7D overriding my adjustment.

[OsmosisStudios]

Originally Posted by quekbc

That's what I did.

Oddly, I depress the shutter button halfway to focus, adjust it, and watch the 7D overriding my adjustment.

If your lens is full-time manual, the body CANT override your adjustment.

[sk66]

Some lenses have A/M some are only A or M (via selector). We're not talking about a manual focus only lens but rather a lens with "manual override".

Set the switch on the camera body to M this will disable the camera's focus motor and the signal to the lens motor. You can set the lens to M via selector (if available). Alternatively you could also switch to "back button focus" which will disable the 1/2 press focus behavior. Otherwise you have to manually focus AFTER 1/2 press of the shutter release (and do not release the 1/2 press until after picture is taken).

[inkista]

I don't think FTM works the way you think it works. Your camera's not smart enough to read your mind as to when you do and don't want autofocus. You have to tell it to be hands off on focus adjustments if you don't want AF.

Basically, you press the shutter button to get focus, then hold the half-press to lock focus, and do your manual adjustment. Once your finger comes off the half-press, you've unlocked the focus, and AF becomes active again.

In situations where I use FTM a lot, I tend to use my C1 custom mode, where I've programmed the camera, via the custom functions, to use back-button AF, with the * and AF-ON buttons reversed, and with the * button now programmed to START autofocus scanning, rather than stop it. Therefore, AF is off and locked by default. I then hit the * button to autofocus on my subject, then take my thumb off the * button, and use MTF to "touch-up" focus.

The AF will always put the lens where it thinks it oughtta be when you activate it. FTM simply means that you aren't going to be grinding/forcing gears by turning the manual focus ring without flipping the AF/MF switch on the lens.

[quekbc]

Well, my aim is to figure out whether it is usual for the camera to override my manual adjustment (even with shutter button depressed during the whole process) when in AF-drive mode AI-Focus and AI-Servo. From what I'm reading so far, I guess it's just me expecting too much from my camera.

A side question, what would the half-depressed shutter button function as if one decides to use a back-button AF?

[inkista]

Originally Posted by quekbc

Well, my aim is to figure out whether it is usual for the camera to override my manual adjustment (even with shutter button depressed during the whole process) when in AF-drive mode AI-Focus and AI-Servo. From what I'm reading so far, I guess it's just me expecting too much from my camera.

Yup. The locking we're talking about will only happen with One Shot AF mode. Given that servo mode is for continually tracking a moving object, the AF is just going to keep going.

A side question, what would the half-depressed shutter button function as if one decides to use a back-button AF?

It's whatever you've set in the custom functions.

Whoah. I just checked out the 7D custom function menus on this, and it's completely different from everybody else's. You've got waaaay more controls and choices for this than a simple back-button setup. You can set up the *, AF-ON, and shutter half press individually, and holy--! you can use the DoF preview button, and the lens's AF-stop button instead of a back button if you wanted. I'd say go play with C.Fn. IV-1: Custom controls and see what works for you.

My personal preference is to use the shutter half-press for AE-lock, if I'm doing the back-button thing.

[quekbc]

Originally Posted by inkista

Whoah. I just checked out the 7D custom function menus on this, and it's completely different from everybody else's. You've got waaaay more controls and choices for this than a simple back-button setup. You can set up the *, AF-ON, and shutter half press individually, and holy--! you can use the DoF preview button, and the lens's AF-stop button instead of a back button if you wanted. I'd say go play with C.Fn. IV-1: Custom controls and see what works for you.

My personal preference is to use the shutter half-press for AE-lock, if I'm doing the back-button thing.

Whoa... I got excited just by reading this. I've skimmed through the manual guide... Guess I have to set time aside to fully read it.

Thanks a lot!