I'll have to cogitate on this one a while. I think I know most of this
stuff but I wasn't aware that exposure weighting was moving with the
flex focus point.
Chuck Norcutt
On 4/13/2011 1:09 PM, Ken Norton wrote:
>> Thanks. Your summary makes it much clearer. What's interesting is that
>> the matrix metering keys off the focus point rather than the center of
>> the image. Is this a new discovery for you as well?
>
> No. This is also how it work with the majority of cameras that have
> multiple focus-points. The camera makes an assumption that whatever is
> in focus is what is the subject. And generally, that is the closest
> subject measured, unless it's a donut situation where the outsides
> focus sensors determine close and center is far--in that situation it
> will override the closest-is-subject rule and invert it. A
> "fuzzy-logic" algorithm is involved.
>
> Where you are correct about the center of the image is when you
> override the auto AF-point selection and force it to center-only. When
> you do that, it makes the camera always assume the center and only the
> center AF spot is setting on the subject. Therefore, it is the subject
> which will force the exposure-bias to it. So, depending on how you
> have the camera setup changes the entire dynamic of things quite
> dramatically!
>
> On the A1, there are several menu items of note, which play into this
> whole thing:
>
> Red Menu, Page 1: AEL button. Mine is usually set to Spot AE Toggle if
> I'm wanting to make the camera pretend to have an instant spot button.
> Use Hold if for one-shot, Toggle for multiple. This is the function
> Olympus failed to put into the E-1 for which I've given unending
> grief.
>
> Red Menu, Page 4: AE lock. Mine is sometimes set to Off so it acts
> like the OM system. Otherwise the exposure holds when you have-press.
> When you recompose, the exposure stays the same. The problem there is
> if you do that for focusing reasons and substitute subjects, the
> exposure will skew. As the E-1 functions better with the lock exposure
> on the half-press, I'll turn this on to match it.
>
> Red Menu, Page 4: Spot AE area. This is where things get fun. This is
> set at either Center spot or Flex Focus Pt. Mine is always set at Flex
> Focus Pt so when I'm working on a tripod or have the focus point slid
> around elsewhere, the AEL spot exposure circle with track around right
> with it. Super cool!!! This feature alone is sooooo unique among
> cameras that one is gobsmacked that it isn't implemented on every one.
>
> Of course, since you are in that menu, Make sure Direct MF is turned On.
>
> A couple other settings of note:
>
> Red Menu, Page 1: Flash mode to Fill-flash, Flash control to ADI flash.
>
> Red Menu, Page 3: Monitor amp. Normal. Manual exp. set to Exp.
> priority. Mag. button to FlexMagnifier
>
> AG
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