metering confusion

paigew · Jan 12, 2012

My camera (t3i) has 4 different metering modes evaluative, center-weight, spot, and partial (I think...I would go check but I am bouncing my baby in the bouncer and it took me 30 minutes to get him to sleep!). I am so confused by the different modes and when I use them I don't really notice any differences in the modes. Maybe I am not using them in the right situations? Or maybe I am not using it correctly? Does the light evaluation automatically happen when you 1/2 press the shutter to focus? (on selected focus point?).

I read this article but I am still confused as to what the meter does. Today my baby was in front of a sunny window, I took a photo of him with focus point focusing on him. I did this on each metering mode and all the photos turned out the same (well from what I can tell...haven't uploaded them yet). I was expecting differences in the way he was lit up vs the window being blown out, is this not accurate? Does this even make sense haha

:mrgreen:

MTVision · Jan 12, 2012

paigew said:
My camera (t3i) has 4 different metering modes evaluative, center-weight, spot, and partial (I think...I would go check but I am bouncing my baby in the bouncer and it took me 30 minutes to get him to sleep!). I am so confused by the different modes and when I use them I don't really notice any differences in the modes. Maybe I am not using them in the right situations? Or maybe I am not using it correctly? Does the light evaluation automatically happen when you 1/2 press the shutter to focus? (on selected focus point?).

I read this article but I am still confused as to what the meter does. Today my baby was in front of a sunny window, I took a photo of him with focus point focusing on him. I did this on each metering mode and all the photos turned out the same (well from what I can tell...haven't uploaded them yet). I was expecting differences in the way he was lit up vs the window being blown out, is this not accurate? Does this even make sense haha :mrgreen:

How do you adjust your shutter speed and aperture? What leads you to picking the settings.

With spot metering - it only works on the center focal point. You would point it at say skin and then set your exposure to like a stop over for caucasian skin (I may be wrong). If you wanted a silhouette you would point at the window and adjust settings based on your meter reading. You know the little meter right +------0------ - (something like that).

Evaluative kind of measures the average of the scene. So if you have a lot of bright light - your subject would probably come out underexposed to compensate for the bright light

Center weighted means just that an then it averages out the scene (I think).

MTVision · Jan 12, 2012

Set your meter to spot and then point your camera at different things (bright and dark). Your meter should move.

Spot meter doesn't work in any of the priority modes unless you lock your exposure on whatever you are spot metering for.

KmH · Jan 12, 2012

You have to look at the light meter in the camera viewfinder.

The light meter isn't shown in the viewfinder if you use AUTO mode.

Rephargotohp · Jan 12, 2012

On Canon,
Evaluative Metering views the whole scene, but gives priority to what is under the selected Focus point. So say you used the left focus point and a person was there. It would give priority to that person even though they aren't centered and then judges that in relation to the rest of the screen.

ONLY in evaluative mode, will a half push of the Shutter button, will iut lock both Focus AND exposure so if you recompose the exposure will not change (in AV TV and P Modes)

The other three revolve around the center of the viewfinder.

Center weighted views the whole viewfinder but gives more "weighting" to things that are in the center.

Spot metering, meters a small area (about5%) of the center of the view finder

Partial does the same just in a larger area.

Spot and Partial ignore the rest of the viewfinder

The big difference with Center, Spot and partial is that a half shutter push does NOT lock exposure. So if you meter and then recompose (in AV TV and P modes) the exposure will change when you recompose unless you use the Exposure Lock Button (*) on the back of the camera.

Many times you will get the exact same exposure no matter what mode you use. But in a heavy back lit situation, spot would work better, PROVIDED IT IS on your subject, If Spot is on the background, you will get a well exposed background and a dark subject.

Don't however expect different metering to fix problems with dynamic range. If you have a subject in the shade and a sunny background. No matter what metering you use. It will not fix the large difference in brightness between two areas

paigew · Jan 12, 2012

maybe I am jumping into metering too quickly. I usually just adjust my settings based on the way the photos are turning out. If they look to dark on the lcd then I up the iso or lower ss, etc. I take a 'practice shot'. I really don't even look at the little +-------0------- - thing. I'm not sure I understand what you mean, isn't the point of metering modes so that you don't have to over/under expose the subject?

paigew · Jan 12, 2012

KmH said:
You have to look at the light meter in the camera viewfinder.

The light meter isn't shown in the viewfinder if you use AUTO mode.

I always look thru the viewfinder and always use Manual shooting mode....

Josh66 · Jan 12, 2012

Basically, the different metering modes change how much of the scene the meter is looking at. Evaluative basically looks at the whole thing. Center Weighted still looks at the whole thing, but it puts more emphasis on the center. Partial is like Spot, but with a bigger spot. Spot only looks at a small area in the center and ignores everything else.

MTVision · Jan 12, 2012

paigew said:
maybe I am jumping into metering too quickly. I usually just adjust my settings based on the way the photos are turning out. If they look to dark on the lcd then I up the iso or lower ss, etc. I take a 'practice shot'. I really don't even look at the little +-------0------- - thing. I'm not sure I understand what you mean, isn't the point of metering modes so that you don't have to over/under expose the subject?

Your metering mode determines what your meter does. Doesn't matter what meter mode your using if that's the way your shooting. The cameras meter isn't perfect and it's not automatic. Putting your meter to 0 will not always give you a perfect exposure. It's just a reflected light meter.

paigew · Jan 12, 2012

okay, so the metering mode just a tool to help you adjust your settings? It doesn't actually do anything to your image unless you change your settings based on the reading? I thought it did something on its own, but now this is making more sense that you would adjust settings according to the readings you get when you meter the shot/area.

paigew · Jan 12, 2012

I'm going to play around again tomorrow and report back. thanks for the info

MTVision · Jan 12, 2012

An if you have the option - check your histogram not your LCD. The LCD lies! If you have the rgb histogram option- its Ben better.

Overread · Jan 12, 2012

Excluding some special in-camera fancy auto editing features (which are mostly touchups not major changes so won't affect things too greatly) there are only ever 3 things that control an exposure.
ISO - Shutter speed - Aperture

Features like metering allow you to read the light in advance of taking a photo so that you can select the best 3 settings to get the result you want with the light provided.

I would strongly suggest reading the manual again a few times (far as I recall it should detail basic approaches to shooting) and playing with the camera at the same time. Once you understand how metering works you'll find that you don't have to spend half as much time shooting - reviewing and then shooting again to get the shots to come out looking right.

paigew · Jan 12, 2012

MTVision said:
An if you have the option - check your histogram not your LCD. The LCD lies! If you have the rgb histogram option- its Ben better.

okay well wouldn't the histogram show blow out if I meter for the face? since the background would be blown out? So how do I tell what part is blown...just the blinking white area? Or does the histogram tell you what part is blown. And I do have rgb but I haven't figure out what it says/does yet. Haven't gotten that far in my exploration haha.

paigew · Jan 12, 2012

Overread said:
Excluding some special in-camera fancy auto editing features (which are mostly touchups not major changes so won't affect things too greatly) there are only ever 3 things that control an exposure.
ISO - Shutter speed - Aperture

Features like metering allow you to read the light in advance of taking a photo so that you can select the best 3 settings to get the result you want with the light provided.

I would strongly suggest reading the manual again a few times (far as I recall it should detail basic approaches to shooting) and playing with the camera at the same time. Once you understand how metering works you'll find that you don't have to spend half as much time shooting - reviewing and then shooting again to get the shots to come out looking right.

Thank you! Yes, I have read the manual and read over the metering part several times (its already worn and stays in my camera bag). It just didn't click with me until now that it really doesn't 'do' anything...just a tool or way to guide you. Thats why all my pictures looked the same :blushing:.

Whats the mentoring thing in your siggy...think I'm going to sign up for it, is it still active?