.. is called Manual mode 
But is there any way to achieve a permanent AE lock in Av mode on a Canon 7D? 
If I sound crazy, let me explain.. I was at a male choir concert (Semmarit - a Finnish group) last week and it was quite a show with the singers moving around constantly, dancing etc. I was sitting so far back in the audience that I had the 70-200/2.8 out and wanted to get both group shots as well as individual singers filling the frame. To do this, I wanted to use Av mode and both f/5.6 and f/2.8 to get appropriate DoF for the 2 different scenarios.
But it was not to be. The stage was WHITE, the singers were dressed all fully in BLACK, there was white smoke, there was sunshine peeking in through the clouds now and then. The 7D metering was going crazy with the scene changing constantly from white to black as I covered the stage. So I went Manual, metered off a grey booth wall and all was well. First time I shot anything like that in Manual and it worked a charm.
Except I was locked into an aperture and changing it required me to either remeter off the wall or do some 1/3-stop math in my head (or count the clicks!) so for me not a very quick change of settings. I would have preferred to use Av mode, AE lock *permanently* and then use the top dial to change the aperture with the shutter speed following to keep the same EV. The normal AE lock times out after a couple of seconds unless I keep pressing the * button.. which is not really an option for 2 hours! Or at all when using back-button AF...
Any ideas?
But is there any way to achieve a permanent AE lock in Av mode on a Canon 7D? If I sound crazy, let me explain.. I was at a male choir concert (Semmarit - a Finnish group) last week and it was quite a show with the singers moving around constantly, dancing etc. I was sitting so far back in the audience that I had the 70-200/2.8 out and wanted to get both group shots as well as individual singers filling the frame. To do this, I wanted to use Av mode and both f/5.6 and f/2.8 to get appropriate DoF for the 2 different scenarios.
But it was not to be. The stage was WHITE, the singers were dressed all fully in BLACK, there was white smoke, there was sunshine peeking in through the clouds now and then. The 7D metering was going crazy with the scene changing constantly from white to black as I covered the stage. So I went Manual, metered off a grey booth wall and all was well. First time I shot anything like that in Manual and it worked a charm.
Except I was locked into an aperture and changing it required me to either remeter off the wall or do some 1/3-stop math in my head (or count the clicks!) so for me not a very quick change of settings. I would have preferred to use Av mode, AE lock *permanently* and then use the top dial to change the aperture with the shutter speed following to keep the same EV. The normal AE lock times out after a couple of seconds unless I keep pressing the * button.. which is not really an option for 2 hours! Or at all when using back-button AF...
Any ideas?
