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bryanj Oct 1, 2003 9:02 PM

Does the A70 have EXPOSURE LOCK?
The A70 manual is clear that the camera has FOCUS LOCK and how to use it, but makes no mention of EXPOSURE LOCK. That is:
can you lock in the exposure settings as determined by the light metre, then point the camera somewhere else & shoot?
When you use FOCUS LOCK, does the camera also lock in exposure settings? Can you do one without the other?
The only time that the user manual explicitly states that exposure settings are kept is when you are using photostich mode.
Bryan :roll:

Gimli Oct 2, 2003 4:21 AM

I believe when it does its Focus Lock it also locks the Exposure as well.

Well it seems to when I do panoramic shots with my a60.

As for using them seperately I don't think that can be done.

Anyone else?

richardh Oct 3, 2003 4:10 AM

I am not really farmiliar with the panarama mode but with most modes if you half press the shutter and hit the macro/mf button it kicks the camera into manual focus mode with the manual focus already adjusted to the point you were focused at, so yes you can lock the focus without it locking the exposure. I wasn't even aware that you could lock the exposure (other than holding the button half pressed). Just fyi if you acidentally hit the left/right buttons it will change the focus. To avoid acidentally doing this, half press to focus, hit the macro/mf button to lock the focus, then hit the func button twice to close the manual focus window. It will stay focused at that setting.

bryanj Oct 7, 2003 7:07 PM

According to the Powershot forum, when you half press to get focus lock, it also locks Exposure

richardh Oct 8, 2003 4:57 AM

When you half press the shutter it locks focus and exposure. With the shutter button held half pressed, push the mf button which will lock the focus (actually it just sets it to manual focus at that distance). Then release the shutter without ever full pressing. The focus will be set at that distance. You can half press as many times as you want and each time it will adjust for exposure but the focus will stay at that point. For that matter you can take as many pictures as you want and it will still stay at that focus when you hit the mf button. Just hit the mf button again to unlock the focus. You will notice that after hitting the mf button to lock the focus, the little manual focus bar will be on the lcd. If you hit the left or right buttons it will change the focus. To avoid acidentally doing this, hit the func button twice and the adjustment bar will disapear but it will still be locked at that focal distance.

Melboz99 Oct 8, 2003 11:05 PM

really simple exposure lock
Hey, the easiest way, probably the only way, to lock the exposure on the A70/A60 is to go into full manual. Usually I meter with Av or Tv first, then punch those values into manual. In manual there is nothing changing the exposure but you! BTW, the meter will still tell you how under/over exposed you are in 1/3 stops. For example, if it reads -1-1/3 then you need to open the arpeture four clicks or increase the shutter four clicks, or any combination that leads to four 1/3 stop increases in allowed light.

The key use for this is spot metering. For example, if you want to blend two images together to gain dynamic range, spot meter on the shaddows in Av/Tv, record the values. Then spot meter on the highlights, and record the values. Switch it back over to manual and compose, enter the first values, expose, enter the second values, expose.

BTW, the key use for Focus lock is to be able to focus on one object and meter on another. Or of course, focusing on a moving target, especially kids. Kids often move too and fro without going out of focusing range, but the constant movement throws off the focusing mechanism. Also, if you have the camera hooked up to a tripod and want to use the rule of thirds on a subject, focus once and forget it. This way you will not be recentering on the subject and recomposing with every shot.

These are just two reasons I love my A70, even though it just got it's first malfunction.

richardh Oct 9, 2003 1:02 AM

Figures I would miss the obvious, exposure lock is manual mode. I guess that Is what happens when you try to over think things.

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