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Thread: Discussion on exposure techniques with dslrs

  1. #21

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by wootsk View Post
    There is limitation for electronic sensor. That's one of the reason I am shoot shooting film now. Anyway when you view on your monitor, most monitor doesn't have that high range as well.

    Enjoy some hidden dark truth about most marketing post the Analog to Digital convertor D-range value, but never the actual sensor D-range value. Can actually plot test chart, but I am lazy
    Thank you for your reply

    Do not be discouraged with digital camera dynamic range versus film camera performance. Whilst film does have a better dynamic range, this difference can be drastically minimized with PP as I mention above. The other advantages in digital cameras easily out-perform film. e.g. Instant images without the need for expensive processing, High ISO performance without having to use a grainy film etc.
    The purpose of this thread is for us to understand the limitations and explore ways to get the very best from our digital cameras.

    As I mentioned before, most of the discusion we have had on here is using only one of the exposure methods available to us - spot metering. I tend to use esp metering as my main method. There is also centre weighted metering.
    Kind regards
    Peter My website

  2. #22
    Deregistered wootsk's Avatar
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    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by PeterD View Post
    Thank you for your reply

    Do not be discouraged with digital camera dynamic range versus film camera performance. Whilst film does have a better dynamic range, this difference can be drastically minimized with PP as I mention above. The other advantages in digital cameras easily out-perform film. e.g. Instant images without the need for expensive processing, High ISO performance without having to use a grainy film etc.
    The purpose of this thread is for us to understand the limitations and explore ways to get the very best from our digital cameras.

    As I mentioned before, most of the discusion we have had on here is using only one of the exposure methods available to us - spot metering. I tend to use esp metering as my main method. There is also centre weighted metering.
    I never said that digital camera are bad, I am just sharing about some confused facts about digital camera in D-range that people might not understand about their equipment due to misleading facts from marketing spec release data on Analog to Digital bits and actual D-range of sensor.

    In fact, I do shoot digital when I am traveling for long and not planning to bring around 50+ canister for shooting.

    BTW, lost detail are actually lost, no matter how much amount of PP is applied, they cannot be brought out when they are not there in the first place. Sorry to take up the space here when it is more about exposure techniques with dslrs.

    Center weighted metering from my POV are safer for normal shooting when moving around due to focus more on subject exposure while not neglecting the surround exposure. But if the moment when I start shooting, my main point is only the subject for exposure, Spot is the best choice ba. Over strong sunlight can still lead a center weighted to take a silhouette shot, unless thats the initial purpose.
    Last edited by wootsk; 4th February 2011 at 10:30 PM.

  3. #23

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by wootsk View Post
    I never said that digital camera are bad, I am just sharing about some confused facts about digital camera in D-range that people might not understand about their equipment due to misleading facts from marketing spec release data on Analog to Digital bits and actual D-range of sensor.

    In fact, I do shoot digital when I am traveling for long and not planning to bring around 50+ canister for shooting.

    BTW, lost detail are actually lost, no matter how much amount of PP is applied, they cannot be brought out when they are not there in the first place. Sorry to take up the space here when it is more about exposure techniques with dslrs.
    Thank you for your reply and comments

    You are NOT wasting space and your comments are very valid when discussing this topic. In fact your last comment underlines why this is an important topic to discuss

    I think that PP techniques can be covered later but, as you point out, detail lost can never be recovered in PP. Everything done at the time of shooting is probably more important than PP itself.
    Kind regards
    Peter My website

  4. #24

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by wootsk View Post
    I never said that digital camera are bad, I am just sharing about some confused facts about digital camera in D-range that people might not understand about their equipment due to misleading facts from marketing spec release data on Analog to Digital bits and actual D-range of sensor.

    In fact, I do shoot digital when I am traveling for long and not planning to bring around 50+ canister for shooting.

    BTW, lost detail are actually lost, no matter how much amount of PP is applied, they cannot be brought out when they are not there in the first place. Sorry to take up the space here when it is more about exposure techniques with dslrs.

    Center weighted metering from my POV are safer for normal shooting when moving around due to focus more on subject exposure while not neglecting the surround exposure. But if the moment when I start shooting, my main point is only the subject for exposure, Spot is the best choice ba. Over strong sunlight can still lead a center weighted to take a silhouette shot, unless thats the initial purpose.
    Sorry, missed this when replying to you.

    Yes, I moved over to centre weighted and also to esp. I became unhappy with my ability to control the image exposure properly using spot exposure.

    Can we set up a pol on here to try and establish what exposure methods members on the forum use as a preference. That may be interesting?
    Kind regards
    Peter My website

  5. #25
    Deregistered wootsk's Avatar
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    Default Re: Discussion on exposure techniques with dslrs

    I don't think poll will help as it is more scenario based. Sometime while the location I am having a shoot is a well lighted indoor where the light are constant everywhere, I will just meter once and use manual setting for constant lighting so that my series of shots are all the same in the place rather than having a brighter or darker shot due to uneven metering because of some small shadow or bright window.

    My first even mistake made about relying too much on metering is when taking a simple prize giving few(maybe more) years back. I use AV mode, center weighted and due to different skin color of price taker, I get +- 1 to 2 EV stop of lighting when I could actually meter once and set manual for better result. Thankfully the end result still aren't that bad except for 1 or 2 where I have to Photoshop.
    Last edited by wootsk; 4th February 2011 at 11:31 PM.

  6. #26

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by wootsk View Post
    I don't think poll will help as it is more scenario based. Sometime while the location I am having a shoot is a well lighted indoor where the light are constant everywhere, I will just meter once and use manual setting for constant lighting so that my series of shots are all the same in the place rather than having a brighter or darker shot due to uneven metering because of some small shadow or bright window.

    My first even mistake made about relying too much on metering is when taking a simple prize giving few(maybe more) years back. I use AV mode, center weighted and due to different skin color of price taker, I get +- 1 to 2 EV stop of lighting when I could actually meter once and set manual for better result. Thankfully the end result still aren't that bad except for 1 or 2 where I have to Photoshop.
    Thank you again

    You have given me much food for thought. I have resorted to esp rather than centre weighted or spot. This has given me reasonably consistent results but I must admit I have not yet tried your method. I shall give it a go and see how I get on.
    As I said at the start, I am no expert and I am looking for ideas from forum members based on what works for them.
    Kind regards
    Peter My website

  7. #27

    Default Re: Discussion on exposure techniques with dslrs

    Perhaps one has to look at other camera settings on top of metering & exposure such as contrast & saturation (such as the ones chosen in pic style in the instance of Canon cameras)?

    Based on a few instance of personal experience, high contrast & saturation used (ie. max setting in camera) will tend to block out details on subjects that are mostly white even when exposure is correct.

    In one instance, a reduction of contrast & saturation did bring out the details of the subject's head which was pure white save for the colour of its eyes.
    hasta la justicia siempre

  8. #28

    Default Re: Discussion on exposure techniques with dslrs

    Might I suggest that the starting point is not which metering mode to use. To arrive at a appropriate exposure setting (taking into account that all camera meters are reading for a grey target value that is not identical across brands and in some cases models from the same brand) for your subject, you need to make a starting decision what is your key area of interest in the subject. For the birds it would be detail in white plumage, you could if need to allow for shadow details in some parts of the frame to go featureless. Since its out doors and if you have significant area of sky then this should not be allowed to go 255 say maybe about 220-225 in places. I feel there is slight differences between camera spot, camera center weight or camera evaluative, what is more important is that the most sensitive focal point be used to meter say the area of highlight you need to control the most or in otherwords the one that will most easily go featureless if you do not control it. At the point where the camera system say is correct exposure would make the highlight become a middle grey and not white, a 1/3 to 1 stop more of exposure would make the highlight register as a highlight. Check the lcd (which should have been brightness checked and alined ) look for blinkies a small amount is okay large areas is not. It is easier to do this than to write about it - experiment to understand.

  9. #29

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by ellery View Post
    Might I suggest that the starting point is not which metering mode to use. To arrive at a appropriate exposure setting (taking into account that all camera meters are reading for a grey target value that is not identical across brands and in some cases models from the same brand) for your subject, you need to make a starting decision what is your key area of interest in the subject. For the birds it would be detail in white plumage, you could if need to allow for shadow details in some parts of the frame to go featureless. Since its out doors and if you have significant area of sky then this should not be allowed to go 255 say maybe about 220-225 in places. I feel there is slight differences between camera spot, camera center weight or camera evaluative, what is more important is that the most sensitive focal point be used to meter say the area of highlight you need to control the most or in otherwords the one that will most easily go featureless if you do not control it. At the point where the camera system say is correct exposure would make the highlight become a middle grey and not white, a 1/3 to 1 stop more of exposure would make the highlight register as a highlight. Check the lcd (which should have been brightness checked and alined ) look for blinkies a small amount is okay large areas is not. It is easier to do this than to write about it - experiment to understand.
    Thank you for your reply

    Like you, I feel there is a difference in the effects of setting exposure with the three methods available to us.
    Spot measurement.
    From my experience, and that of one other member here who photographed swans, it seems that the exposure is biased towards the direction of the measured value. If it is white, then the darker tones have less sensitivity and all become darker whilst the highlights have more sensitivity and hence reveal the details in the highlights. In my camera, the measurement area is quoted as 2% of the viewfinder screen.

    In both centre weighted average and camera evaluative (ESP in my case), the measurement area is much larger.

    Centre weighted average.
    As the name implies, it takes the measured value but places a bias on the lightness of the centre of the image. I guess this is similar to automatically adding an exposure offset. decreasing the exposure if the centre of the image is lighter or increasing the exposure if the centre of the image is darker.

    Camera evaluative (ESP in my case)
    Not too sure how this is done but it will be different between manufacturers. If anyone has an explanation I would be very interested.

    I believe you are correct in that these measurements are used to set the mid grey value and the dynamic range will established about that. If the above is correct then, for any given image, the exposure setting will be different and depend upon the method used.

    Your point about looking for flashing on the camera LCD recorded image will enable you to use the exposure offset to compensate for lost detail.

    Hope this makes sense
    Kind regards
    Peter My website

  10. #30

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by cmeptb72 View Post
    Perhaps one has to look at other camera settings on top of metering & exposure such as contrast & saturation (such as the ones chosen in pic style in the instance of Canon cameras)?

    Based on a few instance of personal experience, high contrast & saturation used (ie. max setting in camera) will tend to block out details on subjects that are mostly white even when exposure is correct.

    In one instance, a reduction of contrast & saturation did bring out the details of the subject's head which was pure white save for the colour of its eyes.
    Thanks for your reply

    I believe you are correct in the above but personnally I leave these settings alone on the camera, I use these cotrols in PP where I can see the effect as I make adjustments.
    I shoot in raw and expect to carry out some work in PP to extract as much detail as posible.
    Kind regards
    Peter My website

  11. #31

    Default Re: Discussion on exposure techniques with dslrs

    Fortunately or unfortunately, blinkies and histogram are based on the JPEG interpretation by the camera. As far as I understand, no camera offers RAW analysis. As such, some (in other forums) have choose to use the "faithful"(?) picture setting (for Canon) as they claim it is closest to RAW. For me, I sometimes put +1/3 stop if the blinkies are not in important areas and recover during pp. Even if cannot recover, well, usually if not an enormous patch, can consider content-aware fill to replace the blown parts (but not every one might feel alright to do this).

    Anyone knows hows many stops is 18% gray away from blowing out? Theoretically, my calculations indicates 2.47 stops but I don't know if my concept is correct.
    18 x 2^n = 100
    n = log (100/18) / log 2
    = 2.47

    So in theory, one could compensate up to +2.3 stops but this does not take into account variations within the metered area. Not very useful in general practice (esp matrix metering) but might be helpful in specific cases (spot or center weighted).
    Last edited by CamInit; 5th February 2011 at 10:44 AM.

  12. #32

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by PeterD View Post
    Thank you for your reply

    Like you, I feel there is a difference in the effects of setting exposure with the three methods available to us.
    Spot measurement.
    From my experience, and that of one other member here who photographed swans, it seems that the exposure is biased towards the direction of the measured value. If it is white, then the darker tones have less sensitivity and all become darker whilst the highlights have more sensitivity and hence reveal the details in the highlights. In my camera, the measurement area is quoted as 2% of the viewfinder screen.

    In both centre weighted average and camera evaluative (ESP in my case), the measurement area is much larger.

    Centre weighted average.
    As the name implies, it takes the measured value but places a bias on the lightness of the centre of the image. I guess this is similar to automatically adding an exposure offset. decreasing the exposure if the centre of the image is lighter or increasing the exposure if the centre of the image is darker.

    Camera evaluative (ESP in my case)
    Not too sure how this is done but it will be different between manufacturers. If anyone has an explanation I would be very interested.

    I believe you are correct in that these measurements are used to set the mid grey value and the dynamic range will established about that. If the above is correct then, for any given image, the exposure setting will be different and depend upon the method used.

    Your point about looking for flashing on the camera LCD recorded image will enable you to use the exposure offset to compensate for lost detail.

    Hope this makes sense
    Having read about some having certain personal preference of exposure mode, I really find it is not the end of the world if one were to set it the other way by mistake, eg the intention of using spot to capture a micro subject but wrongly set to av. metering. Very often I will let the preview to serve me notice and I will adjust the EV accordingly. No time to check what king of metering as the insect is not going to wait for you.

    Of course its better get it as right as possible using the correct exposure mode in the first place but having set wrongly, one should not neglect adjusting the EV. So if you were to readjust the EV, you will get the same kind of exposure that you intended to use, isn't it? Yes/No? Moreover, PP would able to recover highlights/ shadow to quite an extend.

  13. #33

    Default Re: Discussion on exposure techniques with dslrs

    Quote Originally Posted by CamInit View Post
    Fortunately or unfortunately, blinkies and histogram are based on the JPEG interpretation by the camera. As far as I understand, no camera offers RAW analysis. As such, some (in other forums) have choose to use the "faithful"(?) picture setting (for Canon) as they claim it is closest to RAW. For me, I sometimes put +1/3 stop if the blinkies are not in important areas and recover during pp. Even if cannot recover, well, usually if not an enormous patch, can consider content-aware fill to replace the blown parts (but not every one might feel alright to do this).

    Anyone knows hows many stops is 18% gray away from blowing out? Theoretically, my calculations indicates 2.47 stops but I don't know if my concept is correct.
    18 x 2^n = 100
    n = log (100/18) / log 2
    = 2.47

    So in theory, one could compensate up to +2.3 stops but this does not take into account variations within the metered area. Not very useful in general practice (esp matrix metering) but might be helpful in specific cases (spot or center weighted).
    Thank you for your reply
    I am not sure if the LCD display is based on the jpg output of the image processor as I do not ask the camera to do the extra processing because all my files are in the raw format.
    The problem with blown highlights is that they can have a dramatic effect during PP. For instance, In trying to tone them down using curves, you are often left with a solid block of burnt highlights which is difficult, and in some cases, imposible to remedy.
    Your calculations look fine to me. I have checked in the E3 and E5 manuals and they allow offset adjustments of +/- 5 stops.
    I take you point about variations in the metered area and will tell you how I approach this below.

    Quote Originally Posted by divinemoment View Post
    Having read about some having certain personal preference of exposure mode, I really find it is not the end of the world if one were to set it the other way by mistake, eg the intention of using spot to capture a micro subject but wrongly set to av. metering. Very often I will let the preview to serve me notice and I will adjust the EV accordingly. No time to check what king of metering as the insect is not going to wait for you.

    Of course its better get it as right as possible using the correct exposure mode in the first place but having set wrongly, one should not neglect adjusting the EV. So if you were to readjust the EV, you will get the same kind of exposure that you intended to use, isn't it? Yes/No? Moreover, PP would able to recover highlights/ shadow to quite an extend.
    Thanks for your reply

    I think I should explain my approach to exposure setting.
    Most of my work is done in daylight conditions and I have no control over the lighting other than positioning myself to ensure the subject has the best lighting conditions posible.
    I use Camera evaluative (ESP in my case) to set the exposure for the scene but make a judgement as to the lightness of the subject relative to the background and set up an exposure offset to give me the best chance of getting the exposure right first time.
    If the subject is brighter than the background, I shall offset the exposure by -1/3 stop (normal conditions) or -1 stop (in bright sunshine).
    If the subject is darker than the background, I increase the exposure by +1/3 or +1/2 stop.
    This approach seems to work in 95% of the cases and I get good exposure first time round.
    It does not seem to work if I use spot nor work as well with centre weighted.

    IMHO Spot metering is ideal where YOU have control over the lighting (e.g. studio situations) but not so where you do not have control. That of course assumes your objective is to create a natural image.
    I am not so sure about the other two modes. I have settled for Camera evaluative (ESP in my case) because, with my camera models, I can reasonably predict the exposure offset I need. I do know that centre weighted is used very well by others.

    I am sorry it has taken so long to reply but we are in different time zones which can make it a little difficult
    Last edited by PeterD; 5th February 2011 at 07:15 PM. Reason: Added + and - symbols
    Kind regards
    Peter My website

  14. #34

    Default Re: Discussion on exposure techniques with dslrs - MORE INFO

    In order to move further forward I have done a little research over the last day or so and now I can define what Camera evaluative (ESP in my case) and Centre weighted exposure metering is about in the case of the Olympus E5 but a similar arrangement will apply to all camera models.

    Camera evaluative (ESP in my case)The E5 has two modes of shooting - through the viewfinder and also from the swivel LCD screen (known as Live View).
    The camera measures differences in the light levels in 324 (Live View), 49 (viewfinder), seperate locations on the image. It then sets the exposure from these measurements.

    Centre weighted Average
    Similar to the above but gives more weight to the light levels at the centre of the image.

    The above explanation confirms to me that Camera Evaluative (ESP in my case) will provide the best chance of getting the exposure right on your first shot. It also will give a better balanced image in terms of light lavels.

    The choice between centre weighted and spot metering would come into play if say the subject was against a bright or dark background and that you do not wish the overall exposure to be affected by the background. Spot metering having the greatest affect.

    Things are a bit clearer now and I shall continue to use Camera evaluative (ESP in my case) exposure metering and fine control the exposure using the offsets.

    I would be interested in hearing your views on this
    Kind regards
    Peter My website

  15. #35
    Deregistered allenleonhart's Avatar
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    Default Re: Discussion on exposure techniques with dslrs - MORE INFO

    hold on ar... i go check...

    i'm not sure if this was what u meant


    this was a shot done in IR photography. the histogram shows only a nice bell curve in the middle area, with almost no detail in the shadow and highlights region. i'm assuming that i got all the data from the scene within that bell curve for there are no spikes too. i edited to shift the bellcurve to extend into highlights and shadows region so as to maximise the detail. for my IR photography i seldom get detail loss from blowouts.

    not sure if that was a good example... not sure if i even done it correctly in the first place hahaha. but i'll try see if i can find a better example of a exposure blended image...

  16. #36
    Deregistered allenleonhart's Avatar
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    Default Re: Discussion on exposure techniques with dslrs - MORE INFO

    ok found one exposure blended shot



    when i did this shot, i shot it in raw. the sky was blown out so as to retain the building details.

    later on in photoshop, i had 2 exposures from the raw file, one where the buildings are exposed correctly and one where sky is exposed correctly, by underexposing the buildings.

    then i merged so u get some relatively dramatic cloud detail and nice buildings

  17. #37

    Default Re: Discussion on exposure techniques with dslrs - MORE INFO

    Quote Originally Posted by allenleonhart View Post
    ok found one exposure blended shot



    when i did this shot, i shot it in raw. the sky was blown out so as to retain the building details.

    later on in photoshop, i had 2 exposures from the raw file, one where the buildings are exposed correctly and one where sky is exposed correctly, by underexposing the buildings.

    then i merged so u get some relatively dramatic cloud detail and nice buildings
    Very nice
    The technique you have applied I have seen done by others. I am afraid that I cannot do this myself for although I have Photoshop CS4, I have never applied the time to learn it.

    The interesting thing here though, I am assuming you created the the merged file from one raw file, is that the camera actually captured detail in both the highlights and shadows. What exposure method did you use?

    The beauty about photography is that it is an art form. You can capture an image exactly as it was or create something more interesting. Well done on your posting.

    I understand that another method of creating this sort of image is to apply HDR. That is taking 3 or so images with different exposures and overlaying them. I have seen several examples of this some of them really good but some others far too harsh. But that is a matter of opinion and people should be able to express themselves in any way they choose.

    This thread has been very interesting because it has made me think, had lots of very good feedback and as a result has built up my confidence. I think I can now look at a potential image and select an exposure mode that will compliment the style I wish to portray.
    Kind regards
    Peter My website

  18. #38
    Deregistered allenleonhart's Avatar
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    Default Re: Discussion on exposure techniques with dslrs - MORE INFO

    mm? my method was to expose subject correctly, and pray hard the raw file has enough details for the sky even though it was overexposed

    but if i were to do it the "right" way,

    1 shot, expose for buildings
    1 shot, expose for sky

    in photoshop, layer mask the sky, and blend

  19. #39
    Deregistered allenleonhart's Avatar
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    Default Re: Discussion on exposure techniques with dslrs - MORE INFO

    in hdr, it isnt exposure blending. what it does is keeping the relative contrast there, while maximising the details in both shadows and highlights region if i am not wrong.

    meaning if ur sky is really bright, it will still be really bright, but u can see the details that would had been washed out.

    exposure blending is dropping the exposure of the sky, such that u can see the details. sky itself would therefore be slightly darker than it was originally.

    correct me if i'm wrong

  20. #40

    Default Re: Discussion on exposure techniques with dslrs - MORE INFO

    Thanks again - really informative post which I found very helpful

    I googled exposure blending and came up with this very useful tutorial.

    Whilst I started this thread to discuss in-camera exposure to maximise detail in a single file, this has extended the discusion by a method of extending the cameras dynamic range to something even closer to a film camera.
    There are a number of images that I have taken that would really benifit from this treatment.

    I am going to give the tutorial a try and then follow this up with a shoot of my own using the techniques in the tutorial. I shall post the result here.

    From what I have read, you cannot use one image but need two to ensure you use the whole of the cameras dynamic range to capture the highlights and separately the shadows. The blending extends the dynamic range. VERY interesting

    Thank you again for posting this
    Kind regards
    Peter My website

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