Need help on metering modes

[t5Nitro]

Could anyone explain the differences between the metering modes? I noticed outside today when I was playing around with the camera that different metering modes made the subject look better.

When do I use what? And how do I use the metering modes? I'm not even sure how to use it; I just switched between them and did nothing different except shoot a picture.

 

[BlueCorn]

I use spot metering and manual exposure mode exclusively.

The different modes determine how much of the frame will be used to calculate the exposure. If you're using manual, using anything but spot will give you unpredictable results. If you're using one of the automatic modes then evaluative is probably your best bet.

 

[t5Nitro]

How to I pick a spot to meter off of. The spot metering worked the best on the white/yellow dog outside today but all I did was aim at the dog and take a picture (dog in center of the shot). I tried to back the image out a bit and give it a lot of sky in the shot but then it metered the sky and everything else was dark. I try to use Av now since it gives me better pictures.

So how exactly do I pick a spot on the picture I want to meter off of myself instead of the camera doing it?

And I don't knw what evaluative is. Just the filled in circle and ( ) around it? Does that just do everything for you? I had that one also, but then the dog seemed more washed out than it should be.

 

[BlueCorn]

When using the spot meter it's important to understand what it's doing. When you point at something and center the meter that doesn't mean that it's the right exposure. That means that it's the correct exposure to render the object as a middle town. If it's lighter than a middle tone it'll be under exposed; darker than a middle tone it'll be over exposed.

The meter isn't telling you what the exposure should be, it's giving you the information that you need to make the correct exposure.

Subject examples:

Bright white with some detail +1.5 - +2
Black with almost no detail -2
Green grass ~ -0.5
Blue sky 0

I generally spot meter on the brightest portion of the scene and set my exposure for that.

For a fun experiment, and to help understand what the meter is doing, take 2 pictures. Use a black piece of paper and a white piece of paper. Use an automatic mode and shoot close enough that the paper fills the frame. After you're done compare the shots. They'll be nearly identical; grey.

Switch to manual mode and start experimenting with tones. Meter on them, shoot them and see how many stops + or - you need to adjust to make them come out right. Once you get used to metering like this and using manual exposure it's actually faster and easier than using an automatic mode and trying to dial in compensation to correct the image.

Cheers

 

[t5Nitro]

I still don't understand it. On my 30D I never payed attention to it but now I want to get better at what I'm doing. So I can't set my exposure compensation because I just tried a darker lit garage against a brighter sky outside. As I move the camera around the exposure compensation thing moves right and left. I aimed at the sky and it was +2 and I aimed in the garage at my black lab and it showed -2. So you said meter off the brightest part of the shot which was +2.

So this means to dial the shutter speed back 6 clicks or something of the like? Obviously if I went 6 clicks ahead on shutter speed (if that's 2 stops) then the sky would look good but then everything else in the garage would be undetectable. Maybe it's easier than I'm trying to think it is.

 

[BlueCorn]

Pick up Peterson's "Understanding Exposure" and read it a couple of times. The only way to get predictable results is to understand what's going on.

 

[t5Nitro]

Cool, I'll check that book out.
Thanks.