Understanding AEL/AFL

Discussion in 'Olympus Cameras' started by IL2AZ, May 29, 2013.

  1. IL2AZ

    IL2AZ Mu-43 Rookie

    18
    Jan 19, 2013
    I'm having some trouble with understanding the function of AEL/AFL, more so the AFL part. I have my OM-D set, so the the Fn1 button functions as AEL/AFL. When I press the button, I see that it displays the "AEL" icon on the screen, and I understand that to mean that now my exposure is locked, so until deactivated, all shots will be taken at the same exposure settings. That part seems easy enough, but now the AFL. I'm not sure how that comes into play. Can someone please explain this function, and under what conditions you would use them? Thanks in advance!
     
  2. abepak

    abepak Mu-43 Regular

    102
    Jan 21, 2013
    SFV, CA
    The way Olympus has their AEL/AFL button set up was a major confusion for me coming from the X Pro1. Basically, you can set the AEL/AFL to either lock exposure or focus. The default is to lock exposure. If you want it to lock focus instead, you have to set it to back button focus mode (SC3 I think) in menu and use that button to set focus... thus "locking" it from changing through the use of the shutter button. The annoying thing is that it doesn't really lock focus... it's getting rid of the shutter button's ability to focus altogether and just reassigning that function to another button.

    I have not found a way to lock focus with the AEL/AFL button outside of this. If I'm wrong, someone please say so.
     
  3. IL2AZ

    IL2AZ Mu-43 Rookie

    18
    Jan 19, 2013
    I appreciate you pointing out that AEL seems to be the default, and locking exposure makes sense to me, so there is consistency between images, if that is what someone is working to achieve. I get lost with the whole back button focusing technique and still what AFL is, how to engage it, and why one would use it. I think I get what you're saying with where it is is in the menu setting. For a long time I've been one of those lucky shooters who can TAKE some great pics, but now I'm trying to focus on technique too, so I can MAKE some great pics.
     
  4. Ned

    Ned Mu-43 Legend

    Jul 18, 2010
    Alberta, Canada
    The AEL/AFL function can be either AEL or AFL, or possibly both depending on how you have set your AF Mode to behave. This behavior is defined in Menu => Sprocket => Button/Dial => AEL/AFL. If you set your chosen AF mode to "Mode 3", that sets your AFL button to what we call "back-button AF". That means that AEL remains at the half-press of the shutter while AF is performed by pressing the AFL button. If you leave it on "Mode 1" (should be the default) then the AEL/AFL button works as an override for the exposure lock function of the shutter release, otherwise AFL and AEL are both tied to the shutter release by default (what I call the "point and shoot" mentality).

    If you set MF to Mode 3, then that adds AF functionality through the back-button so you actually have S-AF + MF.

    Personally, Back-Button AF is the only way I will use AF. It releases you from the frustration of the camera re-focusing itself in order to take a photo, separates your AF and AE so you can meter off something other than what you focus on, and allows you to perform a multitude of tasks such as pre-focusing which are either impossible or frustratingly difficult to do using the default AF behaviors. With back-button AF, the camera focuses when YOU tell it to, not before every shot when it wants to.
     
  5. David A

    David A Mu-43 All-Pro

    Sep 30, 2011
    Brisbane, Australia
    But it DOES lock focus! The point of locking focus is so that your focus point does not change when you press the shutter so focus lock HAS to get rid of the shutter button's ability to change focus.

    After all, in the normal mode what exposure lock does is to get rid of the shutter button's ability to set exposure. It's exactly the same kind of operation and no one complains that exposure lock isn't really exposure lock, just getting rid of the ability to change exposure through the use of the shutter button.

    You say you haven't found a way to lock focus with the AEL/AFL button outside of this. How else could it be done? Once you choose to lock focus, the one thing you don't want to happen is for the focus to change. The point of locking it is to fix it until you unlock it. If you want the shutter button to set focus then you either don't lock focus or you unlock it if you have locked it. You most definitely do not want the shutter button to override your locked focus unless you tell it to do so by unlocking the focus yourself.
     
  6. IL2AZ

    IL2AZ Mu-43 Rookie

    18
    Jan 19, 2013
    Ned, I'm following you so far, and I appreciate the explanation. Now, I'm going to ask what might be a dumb question, but when you say "back button" focusing, what engages that? Is it one of the actual buttons on the camera? And, once you have it set this way, then the shutter button basically just takes the shot? Will the shutter button then act as the AEL, rendering subsequent photos at the same exposure until disengaged?
     
  7. RobWatson

    RobWatson Mu-43 Hall of Famer

    I tried this and it was quite a bit to get used too. Essentially I was just back to MF type workflow which kind of was weird for AF lenses. If I had my wish it would be to program the AEl/AFL to be either AEL or AFL or mode 3 type action except if I don't press AFL then it just acts like mode 1. Or just have AF work perfect every time. I'm not picky, really.
     
  8. monk3y

    monk3y Mu-43 Hall of Famer

    May 14, 2013
    in The Cloud...
    Steven
    This is one of the things that frustrates me on the OM-D, the fn1 button is a bit awkward to reach when shooting so I ended up not using back button focusing.

    The problem is since the camera can't track much, back button focusing is all the more important to allow you to prefocus. :(

    Sent from my GT-N7100 using Mu-43 mobile app
     
  9. abepak

    abepak Mu-43 Regular

    102
    Jan 21, 2013
    SFV, CA
    You would lock focus so that your focusing point doesn't change or reacquire every time you half press your shutter button. It's a huge pain in the butt otherwise, especially in a studio setting or times when you want to meter for a different exposure but want to keep the same focal plane. Back button focusing is to reassign a button (other than the shutter button) to focus. This is usually the button on the back of the camera (hence back button focus i think).

    lol. The way the X-Pro1 was setup was that you can redefine the AEL/AFL button to either lock exposure, lock focus, or lock both by pressing it and this occurs regardless of what the shutter button does. For example, if only AFL: I would half-press the shutter to acquire focus, then press the AFL button and this locks the focus in place. Now the shutter button only acts to meter and to release shutter. If only AEL: Half press shutter to acquire focus and exposure, press AEL. It locks only the exposure and focus can continually be changed via shutter half press (actually with AEL only, I don't think you need to half-press. Can't remember.). If AEL & AFL: Half press, acquire focus and exposure, press AEL/AFL and lock both exposure and focus. Now shutter button only releases shutter.

    I expected the OM-D to behave the same, which probably caused more confusion.
     
  10. Ned

    Ned Mu-43 Legend

    Jul 18, 2010
    Alberta, Canada
    The "back-button" is your AEL/AFL button. Any button you set to AEL/AFL will become your AF back button as soon as you're using Mode 3 for AF behavior. Just choose the Fn button (or red record button) which is most comfortable for you to reach and assign it to AEL/AFL.

    Yes, the shutter button will first lock exposure as normal through the half-press of the shutter, then take the photo when fully depressed. There should also be a mode to put both AEL as well as AFL on the back-button, but I prefer not to so I wouldn't know exactly how to do that.

    You don't need to use Fn1 for back-button AF. You can use any button that can be assigned to AEL/AFL, which includes most of the buttons on the OM-D E-M5.
     
  11. monk3y

    monk3y Mu-43 Hall of Famer

    May 14, 2013
    in The Cloud...
    Steven
    Yeap but there are no other programmable buttons on the back panel, it would be even more awkward to put it on either of the top buttons too. I currently use the top buttons as ISO and "back to center AF" button.




    Sent from my GT-N7100 using Mu-43 mobile app
     
  12. GaryAyala

    GaryAyala Mu-43 Legend

    Jan 2, 2011
    SoCal
    Back Button focus is my most preferred AF for any camera. And yes it does take a bit of trial and error, but I find it the quickest way to focus them re-frame when using the center focus point/box only. It is also very valuable when shooting action/sports. You can just keep pumping the back-button-focus to re-acquire the focus on your subject without worrying about releasing the shutter.

    Gary
     
  13. xdayv

    xdayv Color Blind

    Aug 26, 2011
    Tacloban City, Philippines
    Dave
    Same here.

    And am finally at home with the GH3 with this setting. My other Micro 4/3s were just set to lock focus on half button shutter press. Main reason is the ergonomics of the AEL/AFL button.
     
  14. David A

    David A Mu-43 All-Pro

    Sep 30, 2011
    Brisbane, Australia
    I understand the problem. You've got used to doing it one way and it's always tricky to learn a different process once you've got used to doing things one way. I had a lot of problems with a couple of things (not AEL/AFL) when I moved from an E-P3 to the E-M5. It took time but I've come to prefer the E-M5 to the E-P3. There's no guarantee that will happen for you on this issue but I'm not surprised that you are having problems coming from a different camera made by a different manufacturer when it's easy to run into problems just swapping models from the same manufacturer.
     
  15. quatchi

    quatchi Mu-43 Veteran

    326
    May 17, 2012
    Munich, Germany
    I want to give another example for the advantages of back-button-focus. It comes in handy when you are shooting wildlife. Let's say a lion hidden a bit behind grass or leaves. When you are waiting for the lion to move (perhaps looking your way) you have time to set the focus right with the AFL button. The moment it turns its head, you press the shutter button and hopefully nailed the shot.

    Having focus although on the regular shutter button, invokes the AF before the shot is taken. In that case it is highly likely that the camera focused on the grass/leaves in front of the lion, thus, rendering the lion unsharp. Had that a couple of times before I heard about back-button-focus. :)

    That said, I currently have AEL/AFL assigned to the FN1 button but am not absolutely satisfied with that solution (because of the tiny button).
     
  16. IL2AZ

    IL2AZ Mu-43 Rookie

    18
    Jan 19, 2013
    So Ned, or anyone who can answer this, mode 3 in the menu settings is for AFL, not the combination of AEL/AFL? That's good to know, because I believe mode 1 is the combination of both. Can anyone else confirm this? Thanks!
     
  17. Ross the fiddler

    Ross the fiddler Mu-43 Hall of Famer

    I have my Rec button programmed to toggle from S-AF (or S-AF+MF) to MF & sometimes it is an advantage to use AFL from the Fn1 button (from having Mode 3 set for MF) in situations where it is advantage to fix the focus, not by MF but by AF lock, but most of the time I usually use S-AF(+MF).
     
  18. Ned

    Ned Mu-43 Legend

    Jul 18, 2010
    Alberta, Canada
    You're right, if you don't want to set one of your top buttons for this then the E-M5 isn't the best camera for it. The button I use on all the Olympus Pen cameras besides the original E-P1/2 is the red record button. It's the perfect place for it, and it's a shame the E-M5 doesn't keep that button. The E-P5 still has it, but they shifted it a little further from the thumb so it doesn't interfere with your grip on the camera. I think that would work well.

    Even on my DSLRs I always had the back-button on a "Fn" button on the back, and I guess having it on the back is kind of necessary since you want to be able to use your thumb on the back-button and your finger on the shutter release simultaneously for the quickest action as well as control of both AFL and AEL.

    That is correct. :) It moves AFL to the back-button, while leaving AEL on the "half-press" shutter release.

    If the AF mode you're using is either S-AF or MF, then the back-button will activate as S-AF and acquire focus each time you press it. If your AF mode is C-AF on the other hand, then the back-button will be continuous and will continue focusing as long as you hold down the back-button.

    I set both C-AF and MF to Mode 3. I find it redundant to set S-AF to Mode 3 because MF on Mode 3 gives me S-AF + MF. Leaving S-AF on Mode 1 I still have the choice to go back to shutter focus, but it's not like I ever have any reason to. ;)
     
  19. monk3y

    monk3y Mu-43 Hall of Famer

    May 14, 2013
    in The Cloud...
    Steven
    I see...

    After our conversation earlier, I tried and set up my fn1 as AFL button and changed my controls a bit. I think I can get used to it with a little adjustment in how I grip the camera while shooting. I will give it a test run in the next few days...:smile:

    Thanks
     
  20. RobWatson

    RobWatson Mu-43 Hall of Famer

    So I set up with AF mode as S-AF and use AEl/AFL mode 1. I setup AF mode to MF and use AEL/AFL mode 3 for back button focus and set AEL/AFL to be the red record button.

    Fn2 is set to bring up the MF box.

    So now I get both options with a simple change from S-AF to MF (with MF selected and AEL/AFL set to mode 3 AFL button performs AF!).

    Gives me a chance to get used to back button focus (actually not back but red rec button on top!) and a way to switch back when I get frustrated.

    Fn1 is the key line focus peak trick.

    Nifty part is in MF with AEL/AFL mode3 I can use Fn2 to bring up the MF box and zoom in then press rec button (AEL/AFL) and still get AF inside the zoomed focus box - not sure how useful this is but it is pretty close to the full manual lens operation that it feels right.