I have mine programmed to be the Flash Value lock. My "AF-L" is accomplished by removing my thumb from AF-ON, since I have AF removed from the shutter button. I believe a half-press of the shutter does lock exposure settings. Honestly, I'm not sure exactly what the big benefit is in using exposure lock, either, which I guess is why I programmed the button to do something else.
So I guess I'm not really answering your question, only to say that I find the button useful for a different purpose...
I am curious to see if anyone uses this button, and why they use it!
I use it whenever the area that I want to meter is different than the area I want to be in focus. The button is a way of separating those. If I pick a point that is the correct focus point but the wrong area to base the metering on, I'll meter off of the correct area, hit Exposure Lock, then compose and focus as needed then shoot. I don't use it often but sometimes it will come up, like a sunset where I want the meter to darken/deepen the colors in the far background but I need to have the focus point up in the foreground.
I use it whenever the area that I want to meter is different than the area I want to be in focus. The button is a way of separating those. If I pick a point that is the correct focus point but the wrong area to base the metering on, I'll meter off of the correct area, hit Exposure Lock, then compose and focus as needed then shoot. I don't use it often but sometimes it will come up, like a sunset where I want the meter to darken/deepen the colors in the far background but I need to have the focus point up in the foreground.
I almost always use it I usually use spot meter, meter a few areas of my subject/scene, chose the one that I think is best, lock the meter, then focus and shoot. That is if I dont just use manual mode and use the meter as a guide (you dont have to lock it then). After then I usually check the histogram to make sure the exposure is close to what I wanted
I guess if you always shoot in the middle of the frame and never recompose it wouldnt matter, but your number of shots with a wrong exposure (or not the exposure you wanted) are going to be much higher if you totally rely on the camera to choose the exposure
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So I guess I'm not really answering your question, only to say that I find the button useful for a different purpose...
My site 365 Project
14-24 24-70 70-200mm (vr2)
85 and 50 1.4
45 PC and sb910 x2
http://www.danielkimphotography.com
I use it whenever the area that I want to meter is different than the area I want to be in focus. The button is a way of separating those. If I pick a point that is the correct focus point but the wrong area to base the metering on, I'll meter off of the correct area, hit Exposure Lock, then compose and focus as needed then shoot. I don't use it often but sometimes it will come up, like a sunset where I want the meter to darken/deepen the colors in the far background but I need to have the focus point up in the foreground.
Yep - that's how I use it as well.
http://www.arkreations.com
Nikon D700 | D300 | D80 | SB-800(x2) | SB-600(x2)
Nikkor Lenses: 14-24 f/2.8 | 24-70 f/2.8 | 50 f/1.8 | 85 f/1.4 | 70-200 f/2.8 VR II | 70-300 VR
I guess if you always shoot in the middle of the frame and never recompose it wouldnt matter, but your number of shots with a wrong exposure (or not the exposure you wanted) are going to be much higher if you totally rely on the camera to choose the exposure