metering modes and AF point selection

chad

chad

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Hi Folks :) :)

Could you just go in to some detail on these two things please as I now know what all buttons do (canon 7D) but unsure how to use them correctly for each different subject.

Metering modes -

Evaluative metering
Partial metering
Spot metering
Centre - weighted average


AF point selection.

Auto select
Spot AF
Single point AF
AF point expansion
Zone AF

Questions are -

Metering modes.

I think I understand how each one works :thinking:
But which one do I use at what time??
e.g. x for this situation and z for this situation??

AF point selection.

What to use and when?

Thank you folks :thumbs: :thumbs:
 
It depends :D

The meter will try and average what it is seeing to 18% grey, so on evaluative it is trying to get that result from the whole scene. With spot it is only looking at a small part in the centre so for example a small black square in the middle surrounded by white is going to give a different answer than using evaluative, no matter what you are using interpreting the result is also important, the meter will tell you what's there, it doesn't mean it is going to get it right.

That's why a lot of pro's use an incident light meter, the light falling on a scene is the same but a white swan and a black cormorant would give readings from a spot meter for example, OK so you know what the light should be, do you need to compensate to bring out the darks or supress the whites. The Mk1 brain is a better interpretive tool than the cameras meter which is a guide, pretty good but it isn't infallible.
 
I prefer matrix as my default for all but a few circumstances, all of which have a dark subject against a light background. In that case I'll spot meter (Fn button) and exposure lock. Otherwise I'll use matrix and dial in compensation.

I also prefer single point for precision and choice. I know what I want to focus on, but the camera doesn't always. If things are moving fast and the choice is obvious, then I'll put it in auto select and let the camera work it out. That is for times when I can't change the focus point fast enough or don't want to focus and recompose.

Thanks
Rick
 
I just ignore everything what the camera is telling me and do what I want ;)
 
So what's the difference between single point and spot they both seam to do the same thing

And thanks again
 
chad said:
So what's the difference between single point and spot they both seam to do the same thing

And thanks again
Click to expand...

Spot AF

This mode is basically exactly the same as Single-point AF, but using a smaller, “spot” AF point. As with Single-point AF, you select the focus point to be used. The currently selected point is highlighted, but covers only the smaller point areas inside the highlighted box.

Direct quote from David Busch's Canon EOS 7D (good book, recommended).
 
Focus point selection ie Spot AF is a different issue to spot metering, focus points determine focus funnily enough. Eval, Partial, Centre, Spot are metering choices.
 
did you get a manual with the camera.

i still keep mine in my bag, especailly when im trying to remeber the focusing options
 
Yea got a manuel but its very brief and dose not go into what you use what for when so I'm very much guessing lol
 
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