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Thread: What is the best method for learning how to expose photos correctly?

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    What is the best method for learning how to expose photos correctly?

    Hi Guys,

    It may a difficult question - but I'm hoping someone can answer with some real life examples as to how they learnt. I constantly find my photos having areas that are underexposed and areas that are overexposed. I was wondering how you learn what settings you need to have in place to know your picture's going to turn out right?

    There's so many settings - exposure bias, shutter speed, ISO settings and then you've got the different metering modes too to fiddle around with. It just makes it so hard for a newbie trying to know what works best where. I've kind of got the hang of apertures (only in aperture priority mode) a little over the past few weeks but if I was to do this in manual mode, I'd be lost.

    Also with spot metering - how do you choose where it exposes on or does it just expose the box in the centre of the screen (which you can move around I think)?

    Thanks & happy easter to all!

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    Re: What is the best method for learning how to expose photos correctly?

    Hi Dan,

    I would refer you to the tutorials first and foremost.
    CAMERA METERING & EXPOSURE

    However, this may help.

    Things that affect what the camera does and what is important to you
    Camera mode
    There are five basics on most DSLRs and the better bridge and point and shoots;
    Auto (and preset Scene modes); Camera will vary Shutter speed, Aperture and ISO as it sees fit
    Program; Camera will vary Shutter speed and Aperture, usually at a fixed ISO you have set manually, it also allows you to step through acceptable combinations of exposure, e.g. 1/30 @ f8, 1/60 @ f5.6, etc.
    Shutter priority (Tv); You have manually set a shutter speed and ISO, the camera will set the aperture and warn when it can't achieve correct exposure with this
    Aperture priority (Av); You have manually set an aperture and ISO, the camera will set the shutter speed and warn when it can't achieve correct exposure with this, or if this may result in camera shake
    Manual; You have set ISO, shutter speed and aperture, the camera will warn when it can't achieve correct exposure with this

    Things that affect what the camera tells you the exposure should be;
    Metering modes
    These are how you tell the camera which bit of an image should be considered for setting the exposure

    There are 3 basic types, the names used depend on your camera brand, some cameras may omit Spot;
    a) Average; takes an average of the whole picture
    b) Centre weighted; takes more notice of the central area, so a given brightness picture element near the centre will have more effect than if it is in a corner or on the edge of frame
    c) Spot; usually does take the centre 5% of picture area, can be thought of as the centre focus point, on really higher spec cameras this possibly can be set to use another focus point instead (but I don't know for sure)

    In all cases, the result of this is to tell you, or set, the shutter speed and aperture to make this an average 18% grey for the area metered. Note that many cameras, when used in Auto, or Scene modes, may additionally vary the ISO for you.

    Things you can do to modify the actual shutter speed and aperture used;
    Change the ISO
    In Program, Tv or Av modes, the values of shutter speed and aperture used can be changed by setting a higher or lower ISO to provide say, a shutter speed you can hand hold, or a wider aperture for narrower Dof.
    NB This will NOT change the image exposure (except in Manual), only the values of shutter speed and aperture used.

    Exposure compensation/bias
    You tell the camera to modify the answer its meter worked out by increasing or decreasing the exposure by a fixed amount, you set this as a number of stops offset, 1/3, 1/2. 2/3, 1, or more. This will persist until you change it again.
    Note: this only directly affects exposure in Auto, Program, Shutter (Tv) or Aperture (Av) priority modes, not Manual.
    NB This WILL modify the image exposure, to account for difficult conditions.

    Knowing which mode and method to use when, is the skill of photography!

    Hope that helps,
    Last edited by McQ; 12th July 2009 at 10:06 PM. Reason: correct typos mainly

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    Re: What is the best method for learning how to expose photos correctly?

    Quote Originally Posted by dan88 View Post
    It may a difficult question - but I'm hoping someone can answer with some real life examples as to how they learnt.
    Hi Dan,

    It's a surprisingly quite deceptively deep and wide question, with a lot of "gotchas" along the way.

    Best metering and exposure techniques really depend on a number of factors - and to make things even more complicated, they often all inter-relate.

    Some "food for thought" ...

    - Automatic metering modes often work well, but they can be easily fooled in situations where there's strong back lighting or if the scene is highly reflective or highly unreflective (eg all white (snow) all black (black cat on a black cushion) or containing specular highlights (reflections from the likes of chrome bumpers)

    - Automatic modes can be biased using EC (Exposure Compensation) controls - with digital it's a relatively simple matter to work out how much EC is required by looking for blinkies and evaluating the histogram.

    - Hand-held light meters are wonderful tools - but one needs to know their limitations; when to use them - how to use them - when not to use them.

    - Different scenes require different treatments; in scenes that exceed the dynamic range of the sensor, something is going to have to give.

    - Many people seem to forget that the dynamic range of a sensor falls off dramatically at high ISO settings - something else to throw into the mix.

    So in sumary, ...

    We have not succeeded in answering all of your questions. The answers we have found only serve to raise a whole set of new questions. In some ways we feel we are as confused as ever, but we believe we are confused on a higher level and about more important things.

    ... but seriously, probably the best single answer is manual exposure and spot metering - once you understand it then it gives you the most control, and the most consistant and predictable results.

    I'd suggest that there's no substitute for good old fashioned experimentation - experience - and the asking of specific exposure questions here in forums like this ... slowly it should all start to gel and make sense ... but I don't think that there's any one "magic pill" that can be swallowed.
    Last edited by Colin Southern; 21st March 2010 at 07:15 AM.

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    Re: What is the best method for learning how to expose photos correctly?

    Use digital cameras and see what comes out is the easy answer, the more knowledgable answers are above. Its fairly east (and cheap) to check the preview screen after shooting and that will sometimes allow you to try again straight away, but always let you see what the camera thought it ought to do.
    The metering system in modern cameras can be set to use the whole scene, centre or spot (as already said) but can also be in "clever" mode. The several preset modes will give the camera a clue as to what is in the scene, so that setting the night portrait mode will put it in mind of a foreground subject needing fill flash etc. In this example the camera will probably select a wide aperture (its expecting a poorly lit scene) meter without the flash to set the shutter speed to get the background right and also meter the flash to get the face correctly lit. Its a little more in depth than that in real terms but this gives you the idea.
    In the "non-clever" mode the metering area is down to you to set based on what you know about what you are shooting. If it happens to be a night portrait you might do as above, or you might want to do without the flash if your subject will stay put (statue at night for example).

    The best way to find out is to try it, because with digital the failures are free and immediately obvious.

    I find film shooting difficult as the ISO dial seems to be missing and the preview screen has dropped off the second hand film camera that I got for next to nothing. The easy way to meter for film is to use digital first, play with the settings until it works, then use the same settings on the film camera!

    Go play with it and have fun, you'll find that you've learnt a lot quite quickly.

  5. #5

    Re: What is the best method for learning how to expose photos correctly?

    Dan,

    Lots of good suggestions from the CiC forum members. They all encourage you to experiment, which really is the best way to learn. Consider trying this:

    1. Set camera on iso 100, which is where it should be unless you have a specific reason to change it.

    2. Get yourself a notepad and a pencil.

    3. Sit down somewhere comfortable, with the camera pointing at something that interests you, maybe a landscape?

    4. Put the camera in a fully auto mode and take a photo. Note the aperture and shutter speed, and write these down together with the filename of the photo you just took.
    --> Here we are letting the camera decide what the photo is of, and use all it's clever software to work out what shutter and aperture to use.

    5. Put the camera into manual mode. Either dial in the aperture and shutter speed the camera just used in auto mode, or use the "sunny 16 rule" which says that on a sunny day, using a shutter speed of 1/100th sec you need an aperture of f/16. (In the UK where it's never sunny, I usually use the not-so-sunny 8 rule, and use f/8.) These are just two ways to get a roughly the right exposure. Now take a photo of the same scene as before, and jot down all the numbers again. If you chose the same settings as the camera did in auto, then you should get the same sort of photo. If you dialed in f16 and 1/100th perhaps the scene is underexposed (too dark).
    --> Note that in manual the meter reading is not used at all - you are making the decision about how to take the exposure. Therefore it doesn't matter what metering mode is selected.


    6. Now vary the shutter speed. If you used 1/100th before, try varying between 1/25th to 1/400th. (That's four times the shutter speed, to one quarter of the shutter speed.) Take lots of photos along the way.

    7. Put the shutter speed back to 1/100th, and now vary the aperture from F/4 to F/32. Take more photos.
    --> When you review your photos on the computer, looks for depth of field effects. How much of the shot is in focus?

    8. Have a cup of coffee because this might be getting tedious!

    9. Now try exposure biasing in Av mode. Put the camera into Av, and dial in the settings that you used for aperture at step 5. Provided the sun hasn't set, the camera ought to select the shutter speed it used when in auto mode, or thereabouts. The camera is now using meter readings. Take a shot and note the setting down again.
    --> This is the thing that I remember as the biggest aha! moment when I was learning. The meter reading shouldn't be trusted. Just because the camera thinks it knows what exposure to use, it's not really got much of a clue. It's really just guessing. It's assuming that the camera is pointed at an "18% reflector" like concrete, grass, human skin or sky. It might or might not be.

    10. Now that the camera has suggested a shutter speed to us, we are free to change it. In Av mode you change the shutter speed by dialing in a exposure bias. The bias is set in plus or minus stops, typically with 1/3 stops along the way. Take some shots from -2 to +2 exposure bias. Note down the aperture and shutter speed and also, this time, the bias you dial in.
    --> You should quickly find that a photo with F/16 and shutter speed of 1/100th, with an exposure bias of -1 is taken with a shutter speed of 1/200th. An exposure bias of +1 results in a shutter speed of 1/50th. Adding or subtracting a stop halves or doubles the exposure time in Av mode.
    All I have done here is to describe an experiment to allow you to see what effect making changes on the camera has on the photos. What I do in real life is look at the histogram the camera shows me, which helps me understand how under/over exposed each shot is. After a while you just "get a feeling" for how to bias - I usually work in Av mode.

    Hope some of this is helpful. Don't feel you have to laboriously go through these steps, and certainly not all at once.

    Regards,
    Graham
    Last edited by dendrophile; 10th April 2009 at 11:45 AM. Reason: try->change

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    Re: What is the best method for learning how to expose photos correctly?

    Hi Repliers,

    Thanks for your very informative comments. The metering comment was especially helpful this weekend. Dave, it appears that these metering modes only seem to function on the automatic modes and possibly the Tv/Av modes, correct? I heard somewhere that manual mode is not affected.

    I tried some shots on manual mode this weekend on my trip to Phillip Island in Victoria and I seem to be getting the hang of it. I've been picking the aperture (on manual mode) I'm after and then taking a few shots and looking at the histogram (never used this before) to see what the exposure is like (as well as checking the highlights/shadows). Once I'm happy with the exposure, I shoot the subject. While this may not be a viable option in real life when you have one shot to capture something right, it at least is helping me to understand how the aperture/shutter speed are related and hopefully help me to learn what to use in common situations.

    I'll also have to try Graham's suggestions about writing down what worked when I have a bit of time!

    Cheers all!

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    Re: What is the best method for learning how to expose photos correctly?

    Quote Originally Posted by dan88 View Post
    ...i t appears that these metering modes only seem to function on the automatic modes and possibly the Tv/Av modes, correct? I heard somewhere that manual mode is not affected.
    Hi Dan,

    Metering works in all modes, albeit in a different fashion for manual exposures.

    In regular modes like Av, Tv, Auto etc you're essentially saying to the camera "I trust you - and I'll go with what you think is best" whereas in manual mode it's more a case of "I know what I think - and now I'd like to know what you (the camera) thinks". I like to think of metering in manual mode as being like an "advisery" mode.

    In my opinion, for "regular" photography, nothing beats spot metering (by regular I mean scenes without any back lighting or specular reflections etc). With manual exposure / spot metering it's simply a case of metering the subject and then changing aperture / shutterspeed / ISO etc so that the item you spot metered exposes where you want it to expose.

    eg if you spot meter a brides dress you'd want that to expose close to a highlight - so you'd adjust your exposure so that it exposes around 2 stops over the medium gray (centre) mark. For a dark suit, you'd normally want to expost that around 2 stops under your medium gray point.

    So manual exposure / spot metering gives you total control - if you want to expose a shadow as a highlight (or vice-versa) (for whatever reason) then it's a piece of cake.

    Does this help, or do I need to expand on this a bit more for you?

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    Re: What is the best method for learning how to expose photos correctly?

    Quote Originally Posted by Colin Southern View Post
    Hi Dan,

    Metering works in all modes, albeit in a different fashion for manual exposures.

    In regular modes like Av, Tv, Auto etc you're essentially saying to the camera "I trust you - and I'll go with what you think is best" whereas in manual mode it's more a case of "I know what I think - and now I'd like to know what you (the camera) thinks". I like to think of metering in manual mode as being like an "advisery" mode.

    In my opinion, for "regular" photography, nothing beats spot metering (by regular I mean scenes without any back lighting or specular reflections etc). With manual exposure / spot metering it's simply a case of metering the subject and then changing aperture / shutterspeed / ISO etc so that the item you spot metered exposes where you want it to expose.

    eg if you spot meter a brides dress you'd want that to expose close to a highlight - so you'd adjust your exposure so that it exposes around 2 stops over the medium gray (centre) mark. For a dark suit, you'd normally want to expost that around 2 stops under your medium gray point.

    So manual exposure / spot metering gives you total control - if you want to expose a shadow as a highlight (or vice-versa) (for whatever reason) then it's a piece of cake.

    Does this help, or do I need to expand on this a bit more for you?
    Hi Colin,

    It does help, however I'm a bit confused as to what you mean by a few stops over/under the medium grey mark? I'm not sure I quite understand how the whole "few stops" thing works. Does this have something to do with those 18% grey cards?

    Also, I went shooting out on the weekend trying some manual mode options and leaving the ISO and EV bias alone. The camera picked the ISO (although EV was left at 0 I think). Are you saying on manual mode, if these are set to auto, the metering mode you choose will pick any settings that you havent explicitely defined? Or is it completely different? How do you meter in manual mode by the way? Is it when you hold the shutter button down halfway?

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    Re: What is the best method for learning how to expose photos correctly?

    Quote Originally Posted by dan88 View Post
    It does help, however I'm a bit confused as to what you mean by a few stops over/under the medium grey mark? I'm not sure I quite understand how the whole "few stops" thing works. Does this have something to do with those 18% grey cards?
    Hi Dan,

    It's "Sorta / Kinda" tied in with 18% gray cards. I'm usually somewhat vague about them because some say that camera meters are calibrated to give a central reading then measuring the light reflecting off an 18% gray card -- others say that they're calibrated to a 12% gray card -- others say it's a 13% gray card - and still others say they're calibrated to an ISO standard, which can't be revealed without paying a lot of money! So to (hopefully) avoid confusion I just refer to it as a "medium gray" card.

    Thing about spot metering is that it's very powerful, but at the same time, the camera needs input from us to get the right result ...

    ... if you look at a typical photo - say, a bride and groom, you'll have areas of the photo that shoud be exposed as something bright (eg a highlight) (bride's dress) and areas that should be exposed as something quite dark (Groom's suit) - and many things in between ...

    ... problem is, when you spot meter something the camera has no way of knowing if the thing you're pointing at is something that should be bright - or something that should be dark.

    So ...

    If you use use spot metering with one of the regular exposure modes like Tv / Tv / Auto etc it will assume what you're metering is a medium gray. If you spot meter a white plate, you'll record a gray plate. If you spot meter a black plate, you'll record a gray plate. Spot meter ANYTHING in an automatic mode and the camera will turn it into a medium gray.

    So ...

    When you spot meter something in manual mode the meter will tell you where on the scale it's going to expose relative to a medium gray -- this is where you have to manually change the exposure so that it exposes where you want it to expose. If you're using spot metering and manual exposure control - you spot meter a white dress - and see that the indicator in your viewfinder is in the centre then you know that the white dress is going to expose as a gray dress - the things that were supposed to be gray will in turn be dark gray - and everything else will be totally black (or as we like to joke "the groom will be literally a shadow of his former self!").

    So ...

    When you're spot metering and using manual exposure you have to tell the camera where you want the thing your metering to be exposed ... if it's a white dress then that's normally 2 stops to the right of the centre "middle gray" point - but if you're metering a dark suit then that's probably 1.5 to 2 stops BELOW the center "middle gray" point.

    I think the biggest mistake people make is they think that they can just point the camera at something using spot metering and then take the shot, whereas in reality this only ever works if the thing you're pointed at is medium gray; in all other circumstances you need to move the exposure up or down depending on how reflective the thing is that you're pointing at. (in automatic as well as in manual exposure modes; the difference being that in automatic / Tv / Av type modes you make this adjustment in the form of EC (Exposure Compensation), whereas in manual exposure mode you're responsible for everything.).


    Also, I went shooting out on the weekend trying some manual mode options and leaving the ISO and EV bias alone. The camera picked the ISO (although EV was left at 0 I think).
    If the camera is picking the ISO then you're not in fully manual exposure mode - not sure what model you're shooting with, but some introduce a "safety shift" and change the ISO to keep other parameters within certain bounds - I'd suggest turning such features off while you're trying to get to grips with the fundamentals or it's likely to throw a spanner in the works.


    Are you saying on manual mode, if these are set to auto, the metering mode you choose will pick any settings that you havent explicitely defined? Or is it completely different?
    In manual mode the camera shouldn't be "picking up" anything - it's up to the user to specify Aperture / Shutterspeed / ISO.

    How do you meter in manual mode by the way? Is it when you hold the shutter button down halfway?
    Yes - 1/2 pressing the shutter release normally activates metering. Try it - put the camera into manual + spot metering and point at something white - adjust something until the meter is reading 2 stops to the right - now point at something black (but not in a shadow) and the meter will drop to 2 stops under the mid point - take the shot - and both will expose correctly

    It's a difficult concept to explain using only words - am I making progress here?

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    Re: What is the best method for learning how to expose photos correctly?

    It's a difficult concept to explain using only words - am I making progress here?
    Yes! I'm starting to understand how the whole metering thing works. I was under the impression that you just point and it just exposes the photo correctly, however after reading your post, I now understand that it is recording this as a grey. Would I be wrong in saying that it seems metering helps to record the colours correctly rather than choose the exposure settings so much on modes such as manual?

    If you're using spot metering and manual exposure control - you spot meter a white dress - and see that the indicator in your viewfinder is in the centre then you know that the white dress is going to expose as a gray dress
    This would explain why some of my photos turned out very pale and lacking contrast last time I payed Wollongong a visit. I think I had the thing on spot metering and just pointed it towards the subject, but there was fog around too. Things that were supposed to be grey almost looked white and the photo lacked alot of black.

    If the camera is picking the ISO then you're not in fully manual exposure mode - not sure what model you're shooting with, but some introduce a "safety shift" and change the ISO to keep other parameters within certain bounds - I'd suggest turning such features off while you're trying to get to grips with the fundamentals or it's likely to throw a spanner in the works.
    I'm shooting with a 450D - it has auto ISO in manual mode, which is what I have used a few times in manual mode. I'm starting to understand some of the fundamental aspects of photography, but I thought the auto ISO might give me a bit of a hand to get the grasp of certain other aspects. I see what you mean though - if it's picking an ISO, it's not letting me learn what apertures and shutterspeeds are the correct for situations that I come into because the ISO is enhancing the exposure to counteract the darkness that may be experienced by a small aperture or fast shutterspeed.

    It's "Sorta / Kinda" tied in with 18% gray cards.
    Is it worth purchasing a grey card and then metering this before taking photos (is this how it even works?)?

    Yes - 1/2 pressing the shutter release normally activates metering. Try it - put the camera into manual + spot metering and point at something white - adjust something until the meter is reading 2 stops to the right - now point at something black (but not in a shadow) and the meter will drop to 2 stops under the mid point - take the shot - and both will expose correctly
    What do you do in situations where you're shooting subjects such as landscapes, or is this where a 'grey card' comes in? Does the metering get set automatically when you hold down the shutter release halfway and when it picks the stop and then you fully depress the shutter? Or when you meter a situation, do you manually have to set this in the menu?

    Please excuse my grammar, I'm not the best at structuring sentences!

    Thanks!

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    Re: What is the best method for learning how to expose photos correctly?

    Quote Originally Posted by dan88 View Post
    Yes! I'm starting to understand how the whole metering thing works. I was under the impression that you just point and it just exposes the photo correctly, however after reading your post, I now understand that it is recording this as a grey.
    When you're using metering modes that evaluate the entire scene then for "normal" type scenes it usually exposes it correctly, but it's relying on the amount of variance within the scene to work out an exposure that'll expose the brighter stuff as brighter stuff and the darker stuff as darker stuff, but it's easily fooled ... for example, if you take a photo of a bright but low-contrast scene (like at a ski slope) then the camera will be thinking "wow - so much medium gray!" and that's what you'll get ... which is why you have to apply an EC of +2 when shooting around ski slopes - and of course the opposite for a "black cat on a black rug). The thing to keep primarily in mind is " we know the snow is bright ... we know the cat is dark ... but the camera doesn't - all it can do is look at the range of contrasts in a scene and make an educated guess - often it gets it "spot on" or "close enough" - at other times though it can be hopelessly out.

    Would I be wrong in saying that it seems metering helps to record the colours correctly rather than choose the exposure settings so much on modes such as manual?
    You wouldn't be wrong, but it's probably a dangerous way of thinking about it. Colours will change depending on how light or dark they're made - but in the context of correct exposure that's really a secondary thing. Exposure is more about what elements of the scene are exposed where - once that's right - and you get your white balancing right - then "colour accuracy" pretty much falls into place.

    This would explain why some of my photos turned out very pale and lacking contrast last time I payed Wollongong a visit. I think I had the thing on spot metering and just pointed it towards the subject, but there was fog around too. Things that were supposed to be grey almost looked white and the photo lacked alot of black.
    That sounds like over-exposure - you'd get that if the camera was on one of the auto exposure modes and you spot-metered something darker than a medium gray.

    I'm shooting with a 450D - it has auto ISO in manual mode, which is what I have used a few times in manual mode. I'm starting to understand some of the fundamental aspects of photography, but I thought the auto ISO might give me a bit of a hand to get the grasp of certain other aspects. I see what you mean though - if it's picking an ISO, it's not letting me learn what apertures and shutterspeeds are the correct for situations that I come into because the ISO is enhancing the exposure to counteract the darkness that may be experienced by a small aperture or fast shutterspeed.
    To be honest, I'm not sure how the auto-ISO functions on a 450D in manual mode - in the context of what you're trying to achieve though I would think that's it's counter-productive (in manual mode).

    Is it worth purchasing a grey card and then metering this before taking photos (is this how it even works?)?
    If accurate exposures are important to you then it's a good idea - or consider "going for the double" and getting something like a WhiBal card that also provides a spectrally neutral reference for accurate white balancing. The only thing that's really going to improve on that is a hand-held incident lightmeter.

    What do you do in situations where you're shooting subjects such as landscapes, or is this where a 'grey card' comes in? Does the metering get set automatically when you hold down the shutter release halfway and when it picks the stop and then you fully depress the shutter? Or when you meter a situation, do you manually have to set this in the menu?
    It depends on when I'm shooting - if you look at my gallery (cheap plug = http://pbase.com/cjsouthern) you'll see that most of my landscapes are shot early morning or last light - and in these situations a gray card doesn't help (firstly because I'm nearly always shooting into the light, and secondly because I'm usually shooting multi-minute exposures so I can't use any auto-mode anyway). Your camera has a couple of built-in exposure aids; the histogram and the highlight alert ("blinkies") - as a rule I repy on the blinkies to show me areas of over-exposure, and the histogram to indicate any degree of under-exposure.

    In terms of metering - basically - the camera tells you what it's going to use when you press the release 1/2 way down (for auto-exposure modes) - if the light happened to change between then and pressing the release all the way down you might end up with something slightly difference, but I doubt it's anything you'd even notice normally.

    How's all this sinking in?

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    Re: What is the best method for learning how to expose photos correctly?

    Haha... I think I'm starting to understand this... I had to re-read your post about 3 times for it all to sink in!

    I originally thought that exposure compensation made photos darker or lighter because it was exposing the photo more, but now I see how I think it relates to the colours and how much contrast exists in a scene.

    That sounds like over-exposure - you'd get that if the camera was on one of the auto exposure modes and you spot-metered something darker than a medium gray.
    Maybe this was over-exposure, but I basically had the camera on Tv and took the photo with slow shutter speeds (0"5 or 1s). It was also on AEB with 1/3 because I thought this helped with overcoming overexposure, but now I see this is the wrong attitude to have towards EC.

    I'm not sure how the auto-ISO functions on a 450D in manual mode - in the context of what you're trying to achieve though I would think that's it's counter-productive (in manual mode).
    What ISO would you recommend for most things for learning on? I had a figure of 100-200 for daylight and maybe 400 for night - would this be about what I need to have it set to to learn more about manual mode?

    The only thing that's really going to improve on that is a hand-held incident lightmeter.
    If I purchased one of these, would a whibal/grey card be necessary? I was considering it as my old man said he had one back in the day when he was into SLR's and he said it worked well - although he also had a grey card so... hrmm

    if you look at my gallery (cheap plug = http://pbase.com/cjsouthern)
    No need to plug - I've checked it out extensively

    Your camera has a couple of built-in exposure aids; the histogram and the highlight alert ("blinkies")
    Yeah, I never bothered looking at this when I first got the camera... but after reading some of the above posts, I started using the histogram as well as looking out for extreme highlights using the blinkies:
    Automatic modes can be biased using EC (Exposure Compensation) controls - with digital it's a relatively simple matter to work out how much EC is required by looking for blinkies and evaluating the histogram.
    Also I'm abit confused about Dave's post up the top in relation to what you're saying about EC in manual mode:
    Exposure compensation/bias
    You tell the camera to modify the answer its meter worked out by increasing or decreasing the exposure by a fixed amount, you set this as a number of stops offset, 1/3, 1/2. 2/3, 1, or more. This will persist until you change it again.
    Note: this only directly affects exposure in Auto, Program, Shutter (Tv) or Aperture (Av) priority modes, not Manual.
    Does it work in manual or not?

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    Re: What is the best method for learning how to expose photos correctly?

    [quote=dan88;11091]

    OK - here we go
    I originally thought that exposure compensation made photos darker or lighter because it was exposing the photo more, but now I see how I think it relates to the colours and how much contrast exists in a scene.
    It does - the key point though is does the exposure NEED to be darker or lighter? - and the answer to that depends on whether or not the camera got the metering correct in the first place. If you're metering a scene like snow men on a ski slope the camera won't get it right - it'll get it wrong by about 2 stops (under-exposure) - so +2 stops of EC is needed.

    Maybe this was over-exposure, but I basically had the camera on Tv and took the photo with slow shutter speeds (0"5 or 1s). It was also on AEB with 1/3 because I thought this helped with overcoming overexposure, but now I see this is the wrong attitude to have towards EC.
    AEB (Automatic Exposure Bracketing) in this sense is kinda like a "machine gun" approach - kinda like saying "who the heck knows what's going to be right - so lets just cover our bases and bracket the heck out of it so we know we've got it covered". Nothing inherantly wrong with that per sec, but probably not "best practice"

    What ISO would you recommend for most things for learning on? I had a figure of 100-200 for daylight and maybe 400 for night - would this be about what I need to have it set to to learn more about manual mode?
    Sounds OK - although the more complete answer would probably be "only as high as it needs to be", because the higher you go the more noise you get - normally outside on a sunny day 100 or 200 will be just fine - but even during the day if you have to shoot inside at, say, F5.6 then your shutterspeed will probably be getting quite low - in which case going to a higher ISO will allow you to shoot at a higher shutterspeed and have less change of camera shake.

    If I purchased one of these, would a whibal/grey card be necessary? I was considering it as my old man said he had one back in the day when he was into SLR's and he said it worked well - although he also had a grey card so... hrmm
    My suggestion would be to get a WhiBal card first - get comfortable using it for both exposure and white balancing - and then look at more advanced equipment like light meters (the good ones aren't cheap).

    Re; Histogram

    Yeah, I never bothered looking at this when I first got the camera... but after reading some of the above posts, I started using the histogram as well as looking out for extreme highlights using the blinkies:
    It's a valuable tool - but like most other things in photography there are different ways to use it in differing circumstances. Often with landscape shots, unless you're shooting with GND filters or HDR composities, you'll often run out of dynamic range - so you have to decide if you want to keep highlight detail or shadow detail - blinkies especially tell you what areas are blown so you can decide if they are important areas or not.


    Also I'm abit confused about Dave's post up the top in relation to what you're saying about EC in manual mode:

    Does it work in manual or not?
    EC doesn't work in manual mode. EC varies the exposure by varying aperture or shutterspeed; in manual exposure mode you're already controlling both of these things, so there's nothing that it can change (excluding ISO which isn't normally considered in this circumstance).

    You're going to be the master of exposure by the end of the week

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    Re: What is the best method for learning how to expose photos correctly?

    Hi Dan,
    I just caught the gist of this very long and useful discussion about how to expose correctly. Perhaps this post on my blog can help.

    Regards,
    Peter

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    Re: What is the best method for learning how to expose photos correctly?

    In manual mode the camera shouldn't be "picking up" anything - it's up to the user to specify Aperture / Shutterspeed / ISO.
    Half off-topic: AEB is still available in M-mode. (EOS 400D)
    It behaves like Tv-mode, it adjust the aperture and shutterspeed is kept unchanged.
    For two years i had assumed AEB is not possible in M-mode and yesterday i "discovered" this function.
    It will take me at least two years to understand the additional value of it, as far as i can see it behaves the same as Tv-mode.

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    Re: What is the best method for learning how to expose photos correctly?

    Quote Originally Posted by pixel pete View Post
    Hi Dan,
    I just caught the gist of this very long and useful discussion about how to expose correctly. Perhaps this post on my blog can help.

    Regards,
    Peter
    Pete -- YOUR ALIVE!!! -- Welcome back buddy!

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    Re: What is the best method for learning how to expose photos correctly?

    Quote Originally Posted by d3debian View Post
    Half off-topic: AEB is still available in M-mode. (EOS 400D)
    It behaves like Tv-mode, it adjust the aperture and shutterspeed is kept unchanged.
    Just a little "undocumented aside" to that ...

    On the Canon 1D3 and 1Ds3 - and probably other XXD models as well - there is a custom function that defines whether the Quick-Control-Dial changes aperture or shutterspeed (with the opposite being changed by moving the index wheel). I discovered that if this is changed then whether aperture or shutterspeed is varied during AEB is also changed.

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    Re: What is the best method for learning how to expose photos correctly?

    Hey Colin,
    I'm alive. I've just been busy. Teaching is easy, it's the grading that takes time as I'm sure you've heard.

    In case anyone is interested, here's some recent lessons on
    1. Panning, sorry not the kind for gold
    2. Silhouettes

    I should pop in more often. Thanks for reminding me.

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    Re: What is the best method for learning how to expose photos correctly?

    My suggestion would be to get a WhiBal card first - get comfortable using it for both exposure and white balancing - and then look at more advanced equipment like light meters (the good ones aren't cheap).
    I've seen a few of these around. I might purchase one when I buy my new tripod (either tomorrow or next week). So basically you put the card in the light, and point it at the grey area - then note the EC that the camera meters. Set this in the menu as the EC value and your image should turn out right? Or is there a different way to do it?

    I also saw some lens caps on ebay. They have a WhiBal type of cover that goes on your lens to help you to pick the right white balance. Would these be beneficial (they're $7.50 inc postage so I think it would be a very cheap, handy addition)?

    Often with landscape shots, unless you're shooting with GND filters or HDR composities, you'll often run out of dynamic range - so you have to decide if you want to keep highlight detail or shadow detail - blinkies especially tell you what areas are blown so you can decide if they are important areas or not.
    Are GND filters the ones that you typically use in landscape shots (with the gradient at the top) to tone down the brightness of the sky and help the picture to have a more even appearance?

    You're going to be the master of exposure by the end of the week
    Probably not... but I have taken away quite alot from this thread and my experiences out in the field over the past week. I think I'll PDF it as a future reference as it has alot of jargon explained in layman's terms.

    I think it's time to reward myself with an L series lens - or when my tax cheque comes by anyway!

    Perhaps this post on my blog can help.
    Thanks for this Peter, my brain is a sponge (or at least over the past week) soaking in all this info! Every bit helps.

    I should also check out your panning and silhouettes page when I get a moment.

    Half off-topic: AEB is still available in M-mode. (EOS 400D)
    This is confusing. So it's basically the same as Tv mode in manual mode? How silly!

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    Re: What is the best method for learning how to expose photos correctly?

    Re: WhiBal cards ...

    Quote Originally Posted by dan88 View Post
    I've seen a few of these around. I might purchase one when I buy my new tripod (either tomorrow or next week). So basically you put the card in the light, and point it at the grey area - then note the EC that the camera meters. Set this in the menu as the EC value and your image should turn out right? Or is there a different way to do it?
    There are a few ways to use it for metering, but all are basically variations on the same theme. If you're shooting in manual-eposure mode then make sure the camera is set for spot-metering (1D series camera have the option of automatically changing to spot-metering whenever manual-metering mode is selected).

    Next step, point at the grey card - touch the shutter release to activate metering - and then adjust aperture / shutterspeed / ISO to centre the meter (Canon metering is different to Nikon metering, but I understand that both essentially display the same info).

    Last step, if you're using a WhiBal card then it'll have a black and a white patch - point to the black patch and the reading should drop to -2EV; point at the white patch and the reading should increase to +2EV ...

    ... and you're "good to go"

    Take a test/reference shot - (a) it should show good exposure, and (b) it'll also give you a white balance reference frame.

    I also saw some lens caps on ebay. They have a WhiBal type of cover that goes on your lens to help you to pick the right white balance. Would these be beneficial (they're $7.50 inc postage so I think it would be a very cheap, handy addition)?
    You're probably thinking more of an Expodisc imitation; if it's what I think it is then - personally - I think it's a waste of money (I've got two; don't use either!). What these opaque caps do is blur ("average") the light entering so it essentially become a "gray blob with a colour cast". The theory behond them is sound enough, but in practice they're a PITA to use in that you have to photograph THE LIGHT SOURCE from where the subject is positioned (you DON'T take a reference shot of the subject) - and if mixed lighting or flashes are involved then things just got either (a) much harder, or (b) impossible, whereas a gray card works the same simple way regardless.

    Are GND filters the ones that you typically use in landscape shots (with the gradient at the top) to tone down the brightness of the sky and help the picture to have a more even appearance?
    Yes, although a "more even appearance" isn't so much the issue as the desire to even out the range of the light hitting the sensor so that the sensor can capture it all.

    I think it's time to reward myself with an L series lens - or when my tax cheque comes by anyway!
    Excellent strategy ... one that I like to execute myself once or twice a year ... far better than a glass of the finest champaign.

    This is confusing. So it's basically the same as Tv mode in manual mode? How silly!
    Tv or possibly Av. Regardless of the exposure mode, AEB can still be beneficial

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