Vary shutter behavior with autofocus mode?

[Daniel Browning]

You could add Camera User Setting to My Menu (with Display from My Menu enabled) to make it a little faster to re-register the changes, and also set a longer time delay to standby (to avoid the frustration of changing a setting, waiting for a shot, then waking up your camera to the reverted settings).

Good tips, John (neuro)!

I don't have a 5D2, but if the settings are anything like my 7D and MKIV then I don't think you can link your shutter behavior to your AF modes,

Thanks for the response, Rich. It always helps to get another perspective.

I understand that we may have different requirements, however, I'm not sure why you would want to use AE lock/Metering + AF start with AI Servo.





For me personally, when I am using AI servo, I prefer to use the AF-ON button for tracking, prior to pressing the shutter button to capture the shot. I just find it easier to press the AF-ON button and hold it all the way in for tracking as opposed to pressing the shutter button half way down for tracking.

That is how I use "AE lock/Metering + AF start" too. Shutter="AE lock", AF-ON = "Metering + AF Start". So I think we both use that part of it the same way. It's just the metering/AE-lock we use differently.

The reason that I wouldn't like AE lock/Metering linked to AI Servo is because when I am tracking a car, bird, plane, or athlete, I sometimes find that you can track them from shooting out of the sun and then into the sun, so for this reason I think it is better to let the camera adjust the metering as my subject is moving their position, instead of locking it in.

In that situation I just don't half-press the shutter, avoiding the AE lock. I only half-press when I want to lock the AE or get the I.S. going. Of course, that's a problem if I want I.S. without AE, but such is life when Canon only lets you use two fingers at a time. If the AE lock button was under my left hand, then I could use the shutter for I.S., left hand for AE lock, and AF-ON for focus. In the mean time, I'd probobly just take my finger off the AF-ON for the short time it takes to bang the asterisk button.

I also find that the opposite is true as I wouldn't necessarily want the camera to "Meter + AF Start/Disable" when set to "One Shot." I would prefer the AE lock/Metering to be linked to "One Shot" because you are not going to vary your metering position since your subject is stationary to the angle of the Sun in "One Shot" like you will when tracking a subject over a distance in AI Servo.

Well, that is one valid way to use (or rather, not use) AE lock, but for a lot of my photography it wouldn't work because the camera is missing the exposure even on a scene where nothing is moving, because both the overall lightlevel as well as distribution within the scene are changing. For example:





On Saturday I was shooting a beautiful outdoor wedding. The sun was filtering in through trees, which were moving in the wind in such a way as to cause changes in both the overall light level (about two stops) as well as the location and distribution of spots of sunlight. My desired exposure varied several times a second. Some parts of the scene are always in shade, other parts are always in sun, but the overall light level is oscillating rapidly.





I wanted to keep the exposure of non-sunlit spots the same in all the shots, both to keep from blowing out the sunlit spots but also to save time in post-processing so I don't have to go through and equalize flesh tone brightness between shots that have 10 sunspots and ones with 0.





I couldn't shoot manual because the overall light level was varying several stops from one second to the next. If it weren't for the sunlit spots, I could have just used AE and EC, which would have handled the overall light level changes just fine. But I couldn't because I didn't want the number and location of sunlit spots to affect the brightness of non-sunlit spots from one shot to the next. (Just like you don't want a keylight-only shot to be darker than key+fill+backlight.)





The one thing I did have going for me is that it was always easy to find something that *should* be consistent from one shot to the next. In my case it was grass. I dialed in enough EC to allow metering directly off the non-sunlit grass without blowing the sunlit spots. It so happened that I was using telephoto lenses the whole time, but if I was wide angle I would have switched from CWA (center weighted avg) to spot meter.





All that is just to say that I want to be able to use AE lock even in One Shot mode. []

I use AI servo with AF-ON most of the time, and then when I want the AF-ON button to stop focusing and lock on the subject, I just remove my finger from the AF-ON button and the focusing stops and is locked on the subject. So, in this regard it acts like "One Shot". The only thing that you don't get is the green AF lock confirmation light and the AF lock audible beep.

Agreed, I use it that way too.

For others reading this, I would definitely pick either shutter button AF Start or AF-ON auto focus. I would strongly suggest not to go back and forth with your AF method, because eventually it will mess you up and confuse you, which will cause you to miss some shots. I know this because it happened to me when I first went with the AF-ON button. I was at a friends a wedding and in the heat of the moment I missed some some shots, because I forgot that I had switched the AF-ON button to do the focusing. So, now I always leave it on AF-On.

I've had that happen too. Maybe one solution would be to have the option of setting "AF-ON = One shot AF+shutter" and shutter="totally disabled", so that the AF-ON is the only way to trip the shutter. That way, if you forget that you changed AF-ON to "one shot", the worst thing that happens is you take a shot when you didn't want to, which will remind you that you have to change AF-ON back to AI Servo and re-enable the shutter button. (Of course, then the downside is that if you are on a MF-only lens, you may wonder why the shutter button isn't working... tough problem.)





But even if switching back and forth is like shooting yourself in the foot, I would like Canon to provide me the gun and let me see for myself. []

Even though I don't think the 5d2 can do what you are asking, I thought I would mention the comments above, so that you can see if they will work for you, when you do set-up your custom function settings.

Thanks again.





There are four essential functions I want to peform, and only two fingers to do it (right index and right thumb). If Canon allowed me to hit more than 2 buttons simultaneously, such as by making some buttons accessible to the left hand, then I might do things differently. But as it is, I have to pack a lot of functionality into just two buttons.





The four functions I want are:





1. Optionall lock the AE meter


2. Keep the I.S. going constantly while it's up to my eye.


3. Autofocus for as long as I want it to, and to stop when I want it to.


4. Release the shutter when I say to, not when the camera says to.





I achieve 1, 2, and 4 with the shutter button in "AE lock" mode. The only downside is that the I.S. stops every time I recompose to lock the AE on a different scene, and I can't have the I.S. going without also locking AE. For now I can live with that since it's either momentary and infrequent or I'm not using an I.S. lens anyway. Though I have probably lost a few shots due to the I.S. being unstable after quickly returning from an AE-lock recompose sequence -- it would be nice if there was "eye detect I.S."





I achieve 3 by putting the AF-ON button in Metering + AF Start mode. Since I usually override the metering with the shutter's exposure lock, it's really just "AF Start" mode to me.





The reason why I want to always have the shot in focus is that I spend a lot of time waiting for just the right moment. I may spend 5 minutes looking thorugh the viewfinder as the subject moves around, the focus motor working furiously the whole time, while I just bide my time waiting for the perfect moment. When it happens, *boom*, I take the shot. No waiting for autofocus.





"Single Shot" mode doesn't work in that case: I could constantly press the AF-ON button over and over as the subject moves around, but there are two problems with that. First, it's more tiring than just holding the button down.





Second, single shot is too slow because it starts from scratch every time you press it, throwing the shot way out of focus then homing in. AI Servo stays mostly locked in and only makes fast, minor adjustments. So with AI Servo I wont miss any shots during the time that Single Shot is starting from scratch. And if I want to start from scratch, I just take my finger off the AF-ON momentarily and then hold it down again.





Nothing is more annoying than when you can see the shot in your viewfinder, perfectly focused, and the camera literally refuses to take the picture because it *thinks* it's not in focus. That's why I usually want shutter set to only "AE lock".





As for why I set the shutter to "AE lock" and not "Metering start", it's because I like the ability to take my AE reading from part of the scene (that will tip the AE towards choosing the exposure I want) and then recompose on another part of the scene without losing that AE metering information without taking my finger off the AF-ON to hit the *.





The reason why I set AF-ON to "Metering + AF Start" is because I want to be able to keep the shot in focus all the time, even when I'm not taking a picture. Of course, I could also do that with just the shutter button, but then I'd lose the ability to keep AE lock, manually touch up focus, or stop autofocus if the subject is no longer moving.





I love having separate control of focus and shutter release. In one instant I may hold down AF-ON by itself, wait a little bit for the perfect moment, and then fire off a shot. In the next instant I may hold down AF-ON and the shutter release at the same time, focusing and taking shots in rapid succession without really giving the camera a full block of time to autofocus (like in One Shot mode). In still other times, I may AF-ON while the subject is moving around and then if they settle down do a quick manual focus touch-up and then shoot.
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