Shooting only when in Focus?

petersmart

petersmart

Messages
5,000
Edit My Images
Yes
Can anyone tell me how to get the 450D to trigger only when the focus is spot on?

I think I could do this on my 350D but can't remember how I did it.

At the moment it triggers even when totally OOF.

I want to use this when taking Macro shots so the camera only triggers when in focus so I can rock back and forwards and get a pic only when in focus.

I've tried various settings but all to no avail.
 
Set the camera to OneShot Focus

That means the shutter wont go off untill a focus point is in focus (whether that is a pre-determined point) or all 9 AF Points.

AI Servo will keep hunting for focus, as its used for focussing on moving objects and tracking them, but will take a photograph even when it's not in focus. On the 450D I believe it's the Right Arrow on the Directional Buttons (but not 100% sure)

Hope that helps
Jamie Palmer
 
J4MIE_P said:
Set the camera to OneShot Focus

That means the shutter wont go off untill a focus point is in focus (whether that is a pre-determined point) or all 9 AF Points.

AI Servo will keep hunting for focus, as its used for focussing on moving objects and tracking them, but will take a photograph even when it's not in focus. On the 450D I believe it's the Right Arrow on the Directional Buttons (but not 100% sure)

Hope that helps
Jamie Palmer
Click to expand...

I don't have that - I only have 3 choices;One shot, A1 Focus and A1 Servo.

EDIT - OK I've got it - I set the Focus to One Shot then go to Menu > Custom Functions > Fn no 10 > set #2 (AF/AF Lock, no AE Lock)

And that finally does it.

Thanks for your help.

EDIT #2 - Unfortunately this only works when in AF mode - I can still take OOF pics when in MF mode - anyone know how to do this in MF Mode?
 
Yes, One Shot is the one you want to select if you want it to only fire when in focus

And it is AI Servo, it isn't A1 :) Just for your future reference, but it's still the same as I described above.
 
MF mode is manual focus!
 
You're 'avin a larf.

Have I got this right,

You want to setup the pic using manual focus but don't want the camera to take the pic unless the camera decides it's truly in focus?

So what's the point of manual focus?
 
admirable said:
You're 'avin a larf.

Have I got this right,

You want to setup the pic using manual focus but don't want the camera to take the pic unless the camera decides it's truly in focus?

So what's the point of manual focus?
Click to expand...

YES.

The point is that I've bought a 100mm Macro Non IS.

Since the DOF at 1:1 is VERY small I'm having probs getting truly sharp shots because of movement etc.

Someone suggested rocking back and forwards to get good focus.

So it would maybe help to only have the camera trigger when in focus.

Using AF at such close quarters is not a lot of good because it "hunts" in continuous focus or attains focus in one shot but even pressing the button can be enough to put it out of focus.

Apart from using a tripod and micro focussing rack I'm just trying this.

I can now get it to "focus trigger" in AF but also wanted to try MF.
 
Interesting idea - I see what you're trying to do, i.e. MF but only let you trigger the shutter when the camera acknowledges it's in focus (i.e. the green dot appears in the VF).

I don't think there's a way to do that, I'm afraid :(
 
This is part of the fun/skill of manual focus, a skill that has unfortunately been lost 'these days' due to everyone and their dog relying on the camera doing the work.

If you're not so confident in manual focussing, just keep firing shots while you twist the focus ring. I do this sometimes with two of my old manual primes, as there is no focus confirmation at all in the viewfinder.
 
I've used that very trick with my Macro setup (55-250 and Raynox DCR250) on occasion. Set the camera to one shot, and the lens to autofocus. Ensure that you have the camera/lens in a position that it will never achieve focus (this may require the lens cap to be fitted)... half press the shutter button. Once the lens has finished hunting, fully depress the shutter button. As the lens has failed to lock focus, nothing will happen. Move the camera to the subject, and adjust position until the camera detects focus lock, the shutter will trigger at that point.
 
youre still not going to rule out user error.

example - you half press the shutter and the AF locks, the subject/camera then moves and you take the shot (the camera got AF lock so its happy). you now have an out of focus shot.
 
You must log in or register to reply here.
Back
Top