AF ON button - I finally get it

[hdngo1]

it's great to setup a custom setting for this in say C1 for those of us shooting in low light or astrophotography.

This way you're not forgetting to turn AF off on the focus and re-compose shots.

I no longer use C1/2/3.

Let's say I've set up C1 for a default shooting style I happen to like - say Av mode, f/8, ISO 100 etc. At the start of a session I switch to C1 and begin shooting, but light levels are a bit low so I adjust the ISO setting to 400. During a short pause in shooting, the camera powers down - although I don't even notice this when I pick up the camera because it wakes up instantaneously. But the ISO speed adjustment has been discarded .

That's no good to me, I don't want the camera changing anything without my explicit say-so.

Actually I must check whether my 7D behaves the same way, but I expect it does.

I know what you mean, to overcome that problem, I have the user setting on my menu( the last tab on the menu), Now you can change the stetting on your custom setting, then you can overwrite the old one very quick using your my menu.

 

[samWebster123]

That's a good point steve!

I'll test that on my 7D as well.

 

[Steve Balcombe]

That's a good point steve!

I'll test that on my 7D as well.

I've tested it now - 7D is the same :-(

 

[imqqmi]

I still don't get why back AF on is so helpful. I often shoot a couple of shots, go from full press to half with no problem at all so it may not be for me.

it's great to setup a custom setting for this in say C1 for those of us shooting in low light or astrophotography.

This way you're not forgetting to turn AF off on the focus and re-compose shots.

I no longer use C1/2/3.

Let's say I've set up C1 for a default shooting style I happen to like - say Av mode, f/8, ISO 100 etc. At the start of a session I switch to C1 and begin shooting, but light levels are a bit low so I adjust the ISO setting to 400. During a short pause in shooting, the camera powers down - although I don't even notice this when I pick up the camera because it wakes up instantaneously. But the ISO speed adjustment has been discarded .

That's no good to me, I don't want the camera changing anything without my explicit say-so.

On my 40D, this is exactly why I don't use it anymore, very very frustrating. I would love an option to keep the settings I've changed since saving it to a custom setting. Or a quick way to copy over the settings to the actual Av, Tv or M mode and continue changing settings. Oh well.

--
Kind regards
Imqqmi



http://www.pbase.com/imqqmi

 

[Steve Balcombe]

I still don't get why back AF on is so helpful. I often shoot a couple of shots, go from full press to half with no problem at all so it may not be for me.

There are specific situations where a completely independent button works better than a half-press of the shutter.

One is when using a ring USM lens for manual focusing - instead of actually switching the lens to MF, switch AF to the back button. that way if you simply don't use the back button, you have MF. But you have AF available at any time. This only works with a "full time manual" lens of course.

Another is when pre-focusing such as for speed. Press the AF-On button to prefocus, then you can use the shutter as often as you like and (a) the camera won't change the focus point, and (b) there is no lag due to focusing. This can be done using a half-press, especially if you've learned the knack of going from full press to half, but some people find the separate button easier, especially when it's more than just a couple of shots, and also when wearing gloves.

It won't suit everybody and it certainly doesn't suit every situation, but it can be useful.

 

[imqqmi]

I still don't get why back AF on is so helpful. I often shoot a couple of shots, go from full press to half with no problem at all so it may not be for me.

There are specific situations where a completely independent button works better than a half-press of the shutter.

One is when using a ring USM lens for manual focusing - instead of actually switching the lens to MF, switch AF to the back button. that way if you simply don't use the back button, you have MF. But you have AF available at any time. This only works with a "full time manual" lens of course.

Another is when pre-focusing such as for speed. Press the AF-On button to prefocus, then you can use the shutter as often as you like and (a) the camera won't change the focus point, and (b) there is no lag due to focusing. This can be done using a half-press, especially if you've learned the knack of going from full press to half, but some people find the separate button easier, especially when it's more than just a couple of shots, and also when wearing gloves.

It won't suit everybody and it certainly doesn't suit every situation, but it can be useful.

I can agree with that, but I can't imagine this to be my standard mode of operation. I'll give it a serious go while birding. Pre focusing can sometimes be a boon.

But I think I would forget focusing and get OOF shots Plus gripping the body and reaching for the Af-on button might give me more cramps.

--
Kind regards
Imqqmi



http://www.pbase.com/imqqmi

 

[Steve Balcombe]

I can agree with that, but I can't imagine this to be my standard mode of operation.

Nor mine - it's just another technique to be aware of.

But I think I would forget focusing and get OOF shots

Yes - I've done that!

 

[jonrobertp]

n/t

 

[carlk]

These are all very good uses but the one I like the most is in situations when you need to switch back and forth between AI servo and f&r. For example when shooting wedding and events that you will shoot one with people moving and the next that you need to recompose. The back button allows you to do them on the fly without needing to stop to set the mode and missing shots in between.

I still don't get why back AF on is so helpful. I often shoot a couple of shots, go from full press to half with no problem at all so it may not be for me.

There are specific situations where a completely independent button works better than a half-press of the shutter.

One is when using a ring USM lens for manual focusing - instead of actually switching the lens to MF, switch AF to the back button. that way if you simply don't use the back button, you have MF. But you have AF available at any time. This only works with a "full time manual" lens of course.

Another is when pre-focusing such as for speed. Press the AF-On button to prefocus, then you can use the shutter as often as you like and (a) the camera won't change the focus point, and (b) there is no lag due to focusing. This can be done using a half-press, especially if you've learned the knack of going from full press to half, but some people find the separate button easier, especially when it's more than just a couple of shots, and also when wearing gloves.

It won't suit everybody and it certainly doesn't suit every situation, but it can be useful.