Spot metering
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jgs001
Brian Cox
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Metering for the moon. The example given in Understanding Exposure was of a JCB (Bright yellow) in the bottom of a dark pit. Using spot metering on the JCB, ensured the JCB was correctly exposed, whereas Matrix or Evaluative would have exposed for the overall scene, leaving the JCB overexposed. Which, is almost exactly the same scenario as the moon come to think about it....
That means absolutely nothing to me
That means absolutely nothing to me
Setting the White Balance manually from taking a picture of a grey card (i.e. 18% grey).
So am i right in saying that if im taking for instance a close up of a flower head i would use spot metering
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Well if you were trying to shoot a scene and you wanted to know exactly what the difference in the light levels were in that scene you might want to use a spot meter.
If you can't, or don't want to use the histogram to see where the light levels are falling in the shot, then a meter is great. You can see exactly how bright the highlights are, how dark the shadows are and choose the exposure that gets the detail that's important to you.
Obviously, with many shots the scene is beyond the dynamic range of the camera/film and you need to make the decision about what gets included and what you allow to go to white or to black.
If you can't, or don't want to use the histogram to see where the light levels are falling in the shot, then a meter is great. You can see exactly how bright the highlights are, how dark the shadows are and choose the exposure that gets the detail that's important to you.
Obviously, with many shots the scene is beyond the dynamic range of the camera/film and you need to make the decision about what gets included and what you allow to go to white or to black.
RobertP
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Think we could do with a tutorial on the various metering modes on a camera and how to use them.... I don't have time...any volunteers? (write it yourself or gather information from others in a thread then make a tutorial)
Just a thought
Just a thought
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That means absolutely nothing to me
As I understand it... Get a 18% grey card, point the camera at it in spot metering mode, and balance the meter. Hey presto, bobs yer wotsit.
I believe the inside of Lowepro bags is 18% grey.
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Use a spot meter
It's the same thing really. Except if you had a separate spot meter, they normally have a tighter view for more precise readings.
jgs001
Brian Cox
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So am i right in saying that if im taking for instance a close up of a flower head i would use spot metering
I have a suspicion that the answer would be it depends...
Not very helpfull I know... sorry... Apart from the moon I've not really found much of a use for it to be honest, but that may just be what I'm shooting.Right thank you i dont think im going to understand this right away so i think my best bet is to look for a book on the subject, thank you very much for your comments ...Ray
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I use spot metering for working out the difference between land and sky then using the appropriate ND grad to balance them
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Interesting... I use evaluative or whatever it's called, but point the camera up at the sky, then down at the ground to get my two readings. That way it takes in variations in cloud/light and grass/flower.
That's my theory anyways, though could be way off the mark.
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Generally I pick the lightest and the darkest patches of sky and ground to avoid any blown highlights or crushed lowlights, it does give a lower dynamic range across the rest of the scene but it means no data loss
Ah but hes uneducated a bit like me
:nuts:
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arclight
Oooh that burglar's a cutie
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Brief appreciation of metering modes here:-
http://www.cambridgeincolour.com/tutorials/camera-metering.htm
http://www.cambridgeincolour.com/tutorials/camera-metering.htm
That looks very good if not complicated i will read that through until it sinks in thank you...Ray
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right, i'm a noob but this is how I would think of it.
most metering modes are there to balance the best of the light and dark bits of your subject. the background and the foreground. everything is balance and compromise.
however, spot metering is there incase the point in the very middle of the frame is more important than the background. for example a bird in the sky...if you meter the whole thing then the bird will come out very dark, with little detail because the sky is so light.
spot metering allows you to tell the camera that the centre point is the bit you really want to see most clearly...therefore the bird will be detailed with lots of colours and the sky will take second place, probably coming out very light.
anyone feel free to correct me if I'm way off base
with a 40D you now have spot metering, something that I think is lacking in the 350D
most metering modes are there to balance the best of the light and dark bits of your subject. the background and the foreground. everything is balance and compromise.
however, spot metering is there incase the point in the very middle of the frame is more important than the background. for example a bird in the sky...if you meter the whole thing then the bird will come out very dark, with little detail because the sky is so light.
spot metering allows you to tell the camera that the centre point is the bit you really want to see most clearly...therefore the bird will be detailed with lots of colours and the sky will take second place, probably coming out very light.
anyone feel free to correct me if I'm way off base
with a 40D you now have spot metering, something that I think is lacking in the 350D
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Can someone please explain to me when and why i would use spot metering thank you...Ray
when using the zone system
hahaha dont give your day job up:razz:when using the zone system
Have done got a few links
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Evaluative Metering divides the whole scene into 35 sections and then compares the distribution of brightness within the frame to a database of thousands of sample image profiles. From that comparison it concludes the exposure that it thinks would be best for your scene. Evaluative Metering gives extra emphasis to the area of the scene on and around the active focus point. This can lead to extra surprises when the subject chosen for focusing is unusually dark or light. It is the metering mode that relies on the most intelligence from the camera and the least input from the photographer. Of course, it is not foolproof. It may still be necessary to dial in some exposure compensation.
Centre Weighted Average Metering looks at the brightness of the scene as a whole but pays more attention to the middle (centre) than the edges. This gives a more predictable exposure from the camera as there is no mysterious database of "standard" scenes being consulted and no weighting given to the focus point for exposure. This allows the photographer a slightly easier time of influencing the exposure calculated by pointing the camera at different parts of the scene and anticipating how the camera will behave.
Partial Metering is used when you only want the exposure to be calculated from whatever is in the centre area of the viewfinder. Anything at the edges and corners is ignored completely. This gives more precise control to the photographer to choose what is being metered and to entirely ignore stuff off centre. This might be a good mode for a backlit subject, for example, but in getting your subject exposed correctly your background might get blown completely.
Spot Metering is just like Partial Metering but with a smaller "spot" in the centre of the viewfinder used to meter. This gives very precise control to the photographer to choose exactly what is being metered and to steer the exposure far more accurately than with the less precise metering modes. I use spot metering all the time when I use manual exposure, which I do a lot of the time. If you use spot metering with autoexposure then you will probably need to spend a fair bit of time dialing in EC and/or using AE lock.
I would say that the choice of metering mode largely comes down to personal preference and how much control you want and how involved you want to get in exposing as accurately as possible. Examples of spot metering for manual exposure that I would use are....
- Spot meter off my palm and set exposure to +1 1/3 on the meter
- Spot meter off grass and set exposure to between -1 and 0 on the meter
- Spot meter off a dark subject (e.g. black dog) for which I want to retain detail at -2 on the meter
- Spot meter off a bright subject (e.g. wedding dress or swan) for which I want to retain detail at +2 (as I shoot raw I'd probably go a little higher than +2)
- Spot meter off the brightest thing in the scene that I do not want to clip (e.g. a cloud) at +3 on the meter (I shoot raw and can recover a few blown highlights)
Spot metering makes it easy to accurately pick my metered target and I know whereabout on the scale I need the meter to be for differeent targets. Of course, I'm not perfect either so I still check the histogram regularly (not every shot) and also look for blinkies on the preview image.
In general, the more precise your metering method, the more important it is that you know what you are metering and what meter reading or EC you need for that metered area. This is why, for example, spot metering can be a disaster in autoexposure modes if you meter and recompose without locking the exposure. If you know what you are doing then spot metering gives ultimate control. CWA and Evaluative are less precise but also more forgiving of user error.
Centre Weighted Average Metering looks at the brightness of the scene as a whole but pays more attention to the middle (centre) than the edges. This gives a more predictable exposure from the camera as there is no mysterious database of "standard" scenes being consulted and no weighting given to the focus point for exposure. This allows the photographer a slightly easier time of influencing the exposure calculated by pointing the camera at different parts of the scene and anticipating how the camera will behave.
Partial Metering is used when you only want the exposure to be calculated from whatever is in the centre area of the viewfinder. Anything at the edges and corners is ignored completely. This gives more precise control to the photographer to choose what is being metered and to entirely ignore stuff off centre. This might be a good mode for a backlit subject, for example, but in getting your subject exposed correctly your background might get blown completely.
Spot Metering is just like Partial Metering but with a smaller "spot" in the centre of the viewfinder used to meter. This gives very precise control to the photographer to choose exactly what is being metered and to steer the exposure far more accurately than with the less precise metering modes. I use spot metering all the time when I use manual exposure, which I do a lot of the time. If you use spot metering with autoexposure then you will probably need to spend a fair bit of time dialing in EC and/or using AE lock.
I would say that the choice of metering mode largely comes down to personal preference and how much control you want and how involved you want to get in exposing as accurately as possible. Examples of spot metering for manual exposure that I would use are....
- Spot meter off my palm and set exposure to +1 1/3 on the meter
- Spot meter off grass and set exposure to between -1 and 0 on the meter
- Spot meter off a dark subject (e.g. black dog) for which I want to retain detail at -2 on the meter
- Spot meter off a bright subject (e.g. wedding dress or swan) for which I want to retain detail at +2 (as I shoot raw I'd probably go a little higher than +2)
- Spot meter off the brightest thing in the scene that I do not want to clip (e.g. a cloud) at +3 on the meter (I shoot raw and can recover a few blown highlights)
Spot metering makes it easy to accurately pick my metered target and I know whereabout on the scale I need the meter to be for differeent targets. Of course, I'm not perfect either so I still check the histogram regularly (not every shot) and also look for blinkies on the preview image.
In general, the more precise your metering method, the more important it is that you know what you are metering and what meter reading or EC you need for that metered area. This is why, for example, spot metering can be a disaster in autoexposure modes if you meter and recompose without locking the exposure. If you know what you are doing then spot metering gives ultimate control. CWA and Evaluative are less precise but also more forgiving of user error.