When to use then different metering methods?

JamesAus · 09-28-2008, 02:06 AM

What is probably a straight forward question, but one I'm a bit confused by.

When should you use the metering methods; in what circumstances?

* multi-segement metering
* center-weighted metering
* spot metering

kerrowdown · 09-28-2008, 03:06 AM

You could think of it as a way to get an exposure meter reading of the subject that interests you most in the picture your actually taking, you won’t go far wrong.

Mutli-segment looks at more or less the whole picture (16 segments on the K10D) and tries to balance all the light and dark areas and give you the best average for the whole scene. In landscapes with lots of sky this can lead to the ground being under exposed, where the camera has seen loads of bright sky.

Centre weighted again analyses the whole scene with an emphasis on the centre area of the photograph, so use this if the important subject is fairly central in the shot.

Spot metering only looks at the very centre of the image, so a face in the crowd, lowlight situations or where the exposure is tricky to get a good reading due to lots of dark or light areas in the scene.

Really don’t get to wrapped around the axle with all this, take your pictures look at the results on the camera lcd , if not good try another exposure pattern. It will soon become almost second nature, enjoy your photography first.

*Ash* · 09-28-2008, 03:17 AM

Much the same from me.
Once you understand how each mode works, you'll find you'll decide which is best according to what you want to be properly exposed.

High contrast makes the multi-segment metering less useful as an average metering value will be used, making your subject most likely either over or under exposed.

If you know what you want to meter, switch to spot metering and point the AF point at the subject to lock the AE metering (ensuring you have the 'AE-L with AF lock' feature enabled), recompose and take the shot. The subject will be properly exposed regardless of the other elements of the image.

JamesAus · 09-28-2008, 03:26 AM

Thanks for that reponse, helps

*pingflood* · 09-28-2008, 07:00 AM

Just out of curiosity -- what lens did you use on the last shot? The bokeh is making me dizzy

Marc Sabatella · 09-28-2008, 10:09 AM

Originally Posted by JamesAus

The reason I ask is because of these photos I took today that I'm not happy with the quality, and wondering what I did wrong, that could have affected them, and I wondered if it was the metering methods, as I had it set to multi-segement.

You would need to be more specific abut what you don't like about these pictures. The metering method is just a means to an end - a way of setting a proper exposure. Any of the three metering methods can be used to achieve the same results. The trick is in learning enough about exposure to understand what results you want and how to get those results with each of the methods. And for that, I'd recommend any basic book on photography. I learned what I needed from the National Geographic Field Guide. Bryan Peterson's "Understanding Exposure" is a very common recommendation. Somewhere there is a probably a good web site to explain it all - but I've yet to see a good online tutorial on basic exposure concepts.

But again, the metering method is just a means to an end. You can get the exact same picture using any of the methods - it's all about what you *do* with the method. And by "do", I mean, you can't expect to simply point and shoot and get exactly the exposure you want. You have to know what to point at when metering, how to use the AE-L button or M mode to lock in a particular exposure if you plan on changing your view after metering but before taking the picture, how to use exposure compensation to override the exposure selected by default, etc. That's the sort of stuff that is meant when it is said you need to understand how exposure and metering works.

Now, I assume that with some of these pictures, you are probably finding them too dark. That's a direct result of the sky being dominant in the picture, causing the metering system to create an exposure that does not completely blow the sky out, and that results in your subject being underexposed. So you need to get the camera to create a proper exposure for your subject instead of for the sky - and thus allowing the sky to become blown out. And as I said, that can be done using ny fo the three modes - you just have to know up front that this is your goal and what the methods do.

With multisegment, a common trick is to point at the ground (or some other object that can fill the frame and is about the same value as your subject) and set the exposure (using AE-L or M mode) there, then recompose and take the picture. That works for center weighted too. With spot metering, you could point directly at the subject and set exposure, then recompose if you want to move the subject off-center.

SpecialK · 09-28-2008, 10:24 AM

If you know what you want to meter, switch to spot metering and point the AF point at the subject to lock the AE metering (ensuring you have the 'AE-L with AF lock' feature enabled), recompose and take the shot. The subject will be properly exposed regardless of the other elements of the image.

That is only true if the metered subject is medium tone. As with all metering, it must be interpreted by the photgrapher, and EV compensation may be required.

LittleSkink · 10-01-2008, 03:05 AM

echo what was said about the Understanding Exposure book, its worth getting from the library

The medium tone thing is real important here as each metering method is trying to get the exposure right assuming you want a mid/dark grey (google for 'grey card')

Matrix should be the most reliable, high contrast will spook it as will low key (black dog in shadow) high key (snow scene) where you dont actually want everything to look grey

Centre weighted is ok for portraits or stuff where the edge of the frame is not relevent to exposure

Spot is more specialised, use it when you know why you need it and what you are trying to achieve. Good for stuff like air shows where you want the plane visble and can loose sky detail

I leave my K10 in Matrix unless there is good reason not to. AE-L is very useful too

Lowell Goudge · 10-01-2008, 03:38 AM

It would be useful to explain what you like and don't like about each image, and perhaps post smaller faster downloadable images, but for the first 2 I don;t think there is anything wrong with the metering.

Having said that, I typically use spot metering, and meter off the portion of the scene I want correctly exposed,

This leaves the rest of the image to be dark or blown out as lighting dictates, BUT I also conisder the range of lighting in the scene, and adjust the contrast (I shoot JPEG) to allow for more or less tonal range. I have found that on the K10D the difference between maximum amd minimum contrast is one additional stop (min contrast) of dynamic range in the niddle ranges, and between .75 and one stop at each extreme in the dynamic range.

This can make a big difference in teh tonal quality of the image, and is not at all related to metering of the scene.

*Clicker* · 10-01-2008, 01:39 PM

i think you meant you need help with DOF, TV and Av?

Some shots look out because of contrast (light direction) and subject movent, hence my question above

A good published read for your question It's a good base to start from.

JamesAus · 10-01-2008, 03:53 PM

Thanks very much for the help guys - appreciate it

Has given me a lot to think and read about.

*Canada_Rockies* · 10-01-2008, 09:21 PM

Originally Posted by JamesAus

What is probably a straight forward question, but one I'm a bit confused by.

When should you use the metering methods; in what circumstances?

* multi-segement metering
* center-weighted metering
* spot metering

This month's issue of Outdoor Photographer has an article on exactly that subject. It's very short and well written.

weaponx525 · 10-02-2008, 07:22 PM

I am reading through the Understanding Exposure by Peterson and one thing that I am stuck on is with respect to his metering suggestions and using the K10. I know that the K10 has the option to turn metering on/off for a certain period of time but exactly WHEN is the K10 metering? Is it metering on half-press of the shutter, when you are focused, or when you press the AE-L button?

Personally it appears as if metering of your chosen area ends when you have the little "*" indicated in the viewfinder. Once you have this locked you can then proceed to vary the shutter and/or aperature to achieve what Peterson calls "creative exposure". Honestly I am struggling with knowing when the scene is finished metering and trying to follow his suggestions! Please help!

Marc Sabatella · 10-02-2008, 09:14 PM

Originally Posted by weaponx525

I know that the K10 has the option to turn metering on/off for a certain period of time but exactly WHEN is the K10 metering? Is it metering on half-press of the shutter, when you are focused, or when you press the AE-L button?

You need to make the distinction between metering - the act of reading light - and actually making settings based on that metering.

In the auto modes, it is constantly metering - well, from the moment you half press the shutter until the moment you take the picture. Or until the timer runs out - there is a custom setting to control that. You'll know when that has happened because the viewfinder stops displaying metering info. Anyhow, in the auto modes, it is not only metering, but also constantly adjusting the settings in accordance with the meter. Until you hit AE-L. At which point the settings active at that moment stick. Or, if you don't hit AE-L, then whatever settings are active when you the picture are the settings that get used.

In manual mode ("M"), the camera meters just as constantly, and displays information telling you whether you are under- or over- exposed in its opinion. But because it is manual mode, it never makes any settings based on that information unless you hit the green button to tell it to. Or you can simply move the dials yourself.

Personally it appears as if metering of your chosen area ends when you have the little "*" indicated in the viewfinder.

That's the indicator that shows up when you hit AE-L to lock exposure, yes. But if you never hit that button, that indicator never appears (unless the K10D is more different from previous models than I thought) - the meter is *constantly* telling you what settings it thinks you should use. You aren't supposed to wait for it to finish - it never finishes. it just keeps updating as the scene changes. It responds to changes in the scene practically instantly.

So assuming you want to use AE-L to fix the exposure, then yes, you can apply exposure compensation any time you want after that. But you don't *have* to use AE-L at all - exposure compensation works whether you've used AE-L or not. but if you use AE-L to lock exposure and then apply compensation, then the new exposure is locked. If you don't use AE-L and then apply compensation, then it keeps updating the suggested setting until you take the picture (but with compensation constantly applied).

weaponx525 · 10-04-2008, 08:36 PM

Thank you for the great response. Your answers really help me affirm a few things I had suspicions of, as well as taught me some new methods to metering.

I have been trying out Petersons suggestions and using the AE-L, then modifying the shutter for creative exposures, but I found the challenge now is in 'reading the light' and choosing the proper aperture. Knowing where to meter has also been one great challenge to his methods!

After further reading metering methods, ie metering 'green brother" he mentions -2/3 compensation after the recommended reading. Does this mean metering the green at normal EV and then compensating for your actual photo at -2/3