For the lumix g5, there is the F1 button on the back that I've always used to lock exposure and/or focus. I use it to set a darker or lighter exposure, then sometimes focus and re-compose, and shoot. The thing is, now when I set the exposure this way and take a shot, the exposure locks up and the only way to 'unlock' it it for subsequent shots is to change the aperture, or the exposure compensation, or hit the menu button - it used to be that the exposure would 'unlock' as soon as I stopped holding down the F1 button or after I took a shot. I'm assuming that there's a setting I can change to have the f1 button 'unlock' when I stop touching it, but I don't know where that is. Any suggestions?