Basic metering and focus?

[kat.hayes]

I'm using a 5DM3 to take photos of two kids separated by a few feet outdoors. I use Spot Metering when shooting individual portraits, though I am not sure what the best mode to use to put the priority on good skin tones.

1. Does Spot Metering work well when there are more than one subject in a photo, either together or separated by a few feet?
2. I would like to shoot wide open with a EF 24-70mm 1:2.8 L to get a nice soft background, though I am not able to achieve sharp focus this way since I can only use the focus box to target one of the subjects. What can I do when shooting wide open like this to ensure focus?

Thanks.

 

[privatebydesign]

I'm using a 5DM3 to take photos of two kids separated by a few feet outdoors. I use Spot Metering when shooting individual portraits, though I am not sure what the best mode to use to put the priority on good skin tones.

1. Does Spot Metering work well when there are more than one subject in a photo, either together or separated by a few feet?
2. I would like to shoot wide open with a EF 24-70mm 1:2.8 L to get a nice soft background, though I am not able to achieve sharp focus this way since I can only use the focus box to target one of the subjects. What can I do when shooting wide open like this to ensure focus?

Thanks.

1: Evaluative is pretty hard to beat unless you have severe brightness differences between the subjects and background. Spot is not optimal for two subjects with the 5D MkIII because the metering point is not linked to the focus point, so you will have to meter on the face, lock that or dial it in with exposure compensation or in M mode; then re-frame for composition.

Personally I'd do a few test images to get optimal exposure then leave it at that in M mode.

2: The only thing you can do is position yourself so both subjects are at the same distance from the camera. If you can't do that then you just need to stop down, you can always add a bit of defocus in post, though that isn't ideal.

 

[Mt Spokane Photography]

I'm using a 5DM3 to take photos of two kids separated by a few feet outdoors. I use Spot Metering when shooting individual portraits, though I am not sure what the best mode to use to put the priority on good skin tones.

1. Does Spot Metering work well when there are more than one subject in a photo, either together or separated by a few feet?
2. I would like to shoot wide open with a EF 24-70mm 1:2.8 L to get a nice soft background, though I am not able to achieve sharp focus this way since I can only use the focus box to target one of the subjects. What can I do when shooting wide open like this to ensure focus?

Thanks.

Spot or other AF method does not affect your issue except that you control exactly where the best focus is.


Shooting wide open reduces the depth of field, so one person may be in sharp focus while the other is not. if they are exactly the same distance from the camera, both should be in focus, but if one is further away, then you can try a smaller aperture to get both reasonably sharp.

Your comment about separated a few feet does not tell us for certain if they are different distances from the camera. The depth of field depends on factors like distance to the subject, focal length of the lens, and aperture.

Here is a link to a calculator. For example: your zoom is at 50mm, and the subjects are 7 and 10 feet away. If you focus on the near subject, you have a 1 ft depth of field, and that includes .46 ft in front of the subject. That is unlikely to work unless the subjects are within 6 inches of being exactly the same distance from the sensor.

If you need a few feet depth of field, f/16 would give you 2 ft in front, 5 ft behind. You can focus on a point between the two, about 1/3 of the way and take advantage of the total 7 ft depth of field.

http://www.dofmaster.com/dofjs.html

 

[LDS]

1. Does Spot Metering work well when there are more than one subject in a photo, either together or separated by a few feet?

Spot metering measures a small area of your subject, and interprets it as it was the standard 18% gray surface. It's then up to you to assess the reading and your subject skin tones. Fair skin tones are lighter than 18% gray (up to one stop), of course dark skin tones will be a little darker, and you'll need to compensate while shooting or in post.

Then you'll need to assess any difference among the main areas you need correctly exposed. Even if the subjects are together - and even within a single subject, there could be not so small differences, metering just a single small area may underexpose or overexpose other areas heavily up to clipping - you can make multiple readings (I know it can be difficult with children...), and then dial what you think is the best compromise for your needs. Unluckily the 5D3 doesn't support multi-spot metering and averaging, thereby IMHO spot metering is best used in M mode. Check the histogram, anyway.

Spot metering is very precise, but it can also lead easily to ugly photos when used naively. It may no be the best mode for "action" shooting, it's more useful for precise metering of static subjects (i.e. landscapes).

Anyway, good skin tones often depends also on proper white balance and lack of color dominants harder to remove, especially the less appealing ones, i.e. greens which may give a "cadaveric" look.

 

[Maximilian]

Hi kat.hayes!

I am a little bit puzzled by your question, because you merge four different aspects of photography together and I don't know how to separate them or if you are probably using a wrong term for what you mean.

Reading the good answers of Mt Spokane and privatebydesign I see that they are also interpreting different aspects in your question.

So what am I - what are you - about?
[list type=decimal]
[*]there is focus, and therefore the right usage of AF
[*]there is the setting of aperture to get the right depth of focus (DOF)
[*]there is metering, typically meaning getting the right metering method to get the best exposure
[*]there is white balancing to get the right skin tone/colors
[/list]
(Order of these four aspects does not display any kind of priority. This depends on individual preferences for a specific picture)

AFAIK the metering and the AF method have no influence on the white balance and therefore skin tones, as this is calculated out of the overall color information from the picture.
==> Use files in RAW format to correct this in post if the camera does it wrong.
==> You can use "Custom white balance" together with the "Spot metering" circle to generate a manual white balance (see 5D3 manual p. 140), but I wouldn't recommend that.

When it comes to focus/AF, DOF or metering method I'd refer to the answers of Mt Spokane and privatebydesign.

If our answers don't help, please specify your request more precisely.

 

[Pookie]

Short answer... increase your DOF by using a smaller ap and make sure your background is farther away. You can still get a nice bokeh that way. Your metering and AF selection has little to do with this scenario.

Sometimes wide open isn't the best option...

 

[Sporgon]

I'm using a 5DM3 to take photos of two kids separated by a few feet outdoors. I use Spot Metering when shooting individual portraits, though I am not sure what the best mode to use to put the priority on good skin tones.

1. Does Spot Metering work well when there are more than one subject in a photo, either together or separated by a few feet?
2. I would like to shoot wide open with a EF 24-70mm 1:2.8 L to get a nice soft background, though I am not able to achieve sharp focus this way since I can only use the focus box to target one of the subjects. What can I do when shooting wide open like this to ensure focus?

Thanks.

Just shoot on Evaluative metering and move the focus point to focus on your subject in the normal way when shooting shallow depth of field. The camera will then adjust the exposure accordingly.

So many people don't seem to realise that evaluative metering works around the metering of the focus point, if you like it is an "intelligent" version of spot meter linked to AF point, without the dire consequences if you don't know what you are doing !

 

[kat.hayes]

Thank you for your replies! There were a few facets to my original question, though I received a lot of very useful info, and I think I am starting to get it.

1.) LDS mentioned that Spot Metering may not be the best mode for “action” shooting. Which metering mode is better for moving/running kids? Evaluative?

2.) As a general rule, when using Spot Meter on the face of someone with fair skin, do you simply always meter on a spot on his/her face, and based on the results, always dial in somewhere between .66 - 1 stop?

3.) Is Spot Metering the only metering mode where you need to dial in + or - in the Exposure Compensation based on how dark or light the person's skin tone is?

Thank you!

 

[dak723]

Thank you for your replies! There were a few facets to my original question, though I received a lot of very useful info, and I think I am starting to get it.

1.) LDS mentioned that Spot Metering may not be the best mode for “action” shooting. Which metering mode is better for moving/running kids? Evaluative?

2.) As a general rule, when using Spot Meter on the face of someone with fair skin, do you simply always meter on a spot on his/her face, and based on the results, always dial in somewhere between .66 - 1 stop?

3.) Is Spot Metering the only metering mode where you need to dial in + or - in the Exposure Compensation based on how dark or light the person's skin tone is?

Thank you!

If your questions - and the need to use exposure compensation - are based on your experience with your camera, then by all means continue to do what you are doing if you are getting good results. Otherwise...

In my opinion, spot metering is used for the exact purpose of getting the correct exposure at the exact spot you want, often in cases where it differs substantially from the rest of the composition. So, when spot metering, you should be getting the correct exposure for that spot (faces, in your examples) and should not have to use exposure compensation at all as a general rule. Based on your questions 2 and 3, I would conclude the opposite - when spot metering is used you will not need to use exposure compensation.

If there is not a specific spot you want metered, I would use evaluative for everything else. In fact, evaluative is the only exposure setting I use. I don't shoot portraits, so my answer isn't specific to your portraits/skin tones questions, so keep that in mind.

 

[LDS]

1.) LDS mentioned that Spot Metering may not be the best mode for “action” shooting. Which metering mode is better for moving/running kids? Evaluative?

2.) As a general rule, when using Spot Meter on the face of someone with fair skin, do you simply always meter on a spot on his/her face, and based on the results, always dial in somewhere between .66 - 1 stop?

3.) Is Spot Metering the only metering mode where you need to dial in + or - in the Exposure Compensation based on how dark or light the person's skin tone is?

1) Unless the scene is evenly lit, Evaluative metering will adapt better to the scene, but like any automation, is not perfect. There are some situations where other metering modes may work better. For example, weighted average may work for large subjects in the middle of the frame, when borders are not important. Or (semi)spot metering may be better when shooting small subject moving on a larger darker/lighter background, often out of focus (i.e. birds), or backlit subjects which don't fill the frame. I use evaluative unless there are specific reasons to change. Also evaluative may use AF data to give more weight to the areas which are focused.

2) As a general rule, yes, but you need to be careful about the area you meter. Shadows or bright reflections may lead to the wrong reading.

3) No. Evaluative metering tries to "understand" the scene and optimize exposure, but can fail. Other methods, including weighted average and semispot, are still based on the 18% gray standard. A lot depends on which parts of the frame are skin, and which are not. A portrait where most of the frame is the subject face, for example, is different than an image of a child among her or his toys, maybe on a dark background.

What is important is to understand how the meter "thinks" in each mode, and foresee any correction needed. In doubt, bracket. Anyway, small adjustment can be easily made in post-production, today, especially when shooting RAW instead of JPEG.