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FORUMS Canon Cameras, Lenses & Accessories Canon EOS Digital Cameras 
Thread started 18 Dec 2017 (Monday) 15:37
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BigAl007
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Dec 20, 2017 06:21 |  #46

I have one thing to add to the discussion of separation of AF operation, and release of the shutter, working with a remote release. I'm a BBAF shooter, who removes the AF from the shutter button. I would like to be able to do the same while using a remote release. This is not possible since the remote contacts are pretty much wired in parallel with the shutter button, so to use a remote switch to initiate AF you have to have AF on the shutter button.

I thought I could get around this by wiring a remote lead with two separate buttons, rather than the usual double press you normally see. You can use the button to initiate the AF, and then press the shutter button to take the shot without any problems while you continue to AF. The problem comes if you want to shoot without the AF active, pressing the shutter release button, without the AF active, causes the camera to initiate AF and then fire the shutter. This was never an issue with my old 300D, with the 3.5mm TRS jack. I could use a footswitch with a TS jack positioned so that it contacted the ring contact in the camera to fire the shutter, without initiating the AF. The 300D didn't offer BBAF though.

Mostly when I use the two button release I built for the 50D the AF initiating isn't a real issue, since I would have the AF active anyway. One of the main reasons for building it is that I have Peripheral Neuropathy, which affects the feeling in my fingers. I often find that it is difficult to determine where the first and second presses are, and will press all the way. The click on the camera is not too bad, but many remotes I have tried have had much softer buttons.

Alan


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digital ­ paradise
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Dec 20, 2017 09:40 |  #47

DaviSto wrote in post #18522343 (external link)
With your set-up (both BBF and shutter release focus active), if you are pressing the BBF button to track focus right up to the moment you press the shutter release, there should not be anything unusual happening at the moment when you take the shot. The camera is already as well focused as it is going to get and there is not going to be any further change. What you are missing out on is the ability to stop autofocusing by releasing the BBF button at some desired point and then not have the camera refocus when you take the shot. For BIF, I can't imagine many instances where you would want to freeze focus at some point before you take the shot (or series of shots) ... so you may well feel you are not missing out on very much.

In other types of photography, that ability to completely isolate focusing from taking the shot could be very important, though. But there will still be other ways of achieving the same outcome like using one-shot AF combined with focus lock. To me it's really a question of what is most convenient, and of keeping the number of things I have to think about down to a minimum and maximising the chances of body-learning taking over so that I do the 'right' thing instinctively.

i actually remember setting up the mode dial to separate AF form the shutter and when I noticed no difference AF acquisition, burst shooting and keeper rates I went back to my original setup.


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apersson850
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Post edited 9 months ago by apersson850.
     
Dec 21, 2017 10:20 |  #48

The camera's default setup is that half-pressing the trigger (!) button is the same as pressing AF-ON. They are logically connected in parallel, so pressing one of them, or both, is the same thing.

When I do sports photo, it's frequently in the woods, with bushes and branches around. I prefer then to have AF-ON doing the focusing (Servo AF) and remove focusing from the trigger button altogether. If the athlete then is behind some branches, I can still focus manually and take the picture, without the camera starting any AF operation to get some branches in focus. Note that in this scenario it's nothing the tracking sensitivity can control, as I'm not following the runner from a free area in behind the branches, but start to pick him up among the "focus noise". Thus letting the camera start the focusing operation is in this case usually doomed to fail.

Then there's the situation where you augment the AF-ON button with some extra function, like switching to a certain AF mode (from One Shot to Servo), switching to a certain AF point, changing AF case setting or whatever. In such a case, it makes sense to have AF on both the trigger (there it is again) button and the AF-ON button at the same time, since they don't do exactly the same thing. In this case, the AF-ON button has priority, in that the additional AF setup function will be active as soon as the AF-ON button is pressed, but regardless of whether the trigger button is half-pressed or not.

And yes, if you so prefer, you can program the AF-ON button to be AF-OFF instead, i.e. interrupt an ongoing focusing operation triggered by pressing/holding some other button.

Finally, maybe it's because I'm not a native English speaker that I find trigger button more natural than shutter button. In my language, it's always avtryckare (literally firing button), but never slutarknapp (shutter button). Thus we use the same name for the button on the camera as we do for the firing lever on a gun, and I think you'd call that trigger in English, right? Not shooting button?
Yes, it's all about semantics, and that's sometimes very difficult in a foreign language.


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Dec 21, 2017 10:24 |  #49

After forcing myself to use the BBF when I got my 7D2 I noticed I'm now doing it without thinking about it. It has become natural. I might be doing it on one shot as well. I'll have to pay attention and see. Perhaps I may make a change again.


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Dec 21, 2017 10:46 |  #50

Also that is why I have been posting and hoping Canon would add Drive Mode to the Detail set. For AF-ON I have it set so AI Servo kicks in. For the * button AI Servo, Case 6 and 65 point (61 for 5D4) kick in.

I like to use Zone AF as much as single point and toggle back and forth between the two depending on the conditions. If they added Drive Mode I could leave on Single Shooting and when I pressed a BBF it would switch to HSC - high speed continuous.

I have to leave it on HSC so when I use the shutter for stills I get 2 or 3 frames if I hold the shutter for
too long - which is a minor annoyance.

Since I don't think that will happen so I am considering going back to the C1-3 functions again and breaking it up. For AI servo I'll separate the shutter as I did before when tried the C1-3 functions. It will solve my minor multiple shots issue with One Shot. I never used the C1-3 and I don't really know why I don't like using it. It is a good tool. I'll force myself to adjust.

Too bad as Canon could add so much more to the Detail Set. It would be nice if we could customize what is in that menu.


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