Understanding exposure

Discussion in 'Panasonic Cameras' started by Phil66, Feb 27, 2012.

  1. Phil66

    Phil66 Mu-43 Regular

    130
    Dec 27, 2011
    Ello all,
    I have been reading the very interesting Understanding Exposure by Bryon Peterson.
    In it he keeps saying things like "I metered off the blue sky which indicated a 1/15 sec. exposure and recomposed", and "I adjusted the shutter speed until 1/125 sec. indicated a correct exposure in the viewfinder". Can I relate any of this type of comment to my G3?
    I apologise for my lack of understanding.
    Cheers

    Phil
     
  2. Squidz

    Squidz Mu-43 Regular

    38
    Feb 8, 2012
    Red Deer, Alberta
    Indeed these principles will apply to your camera and any other for that matter. In this example, a blue sky is very close to an 18% grey card that most cameras are designed to meter for and a meter reading of blue sky during the day is very accurate.

    Now what you do with that number is very dependent on what you are trying to accomplish, but it's certainly a good baseline.
     
  3. ean10775

    ean10775 Mu-43 All-Pro

    Jan 31, 2011
    Cleveland, Ohio
    Eric
    What he is referring to is simply shooting in full manual mode and 'zeroing out' your meter - as in making sure it is indicating neither underexposure or overexposure (i.e., making sure the line is in the center of the meter - I'm not sure how this looks on a G3)
     
  4. Promit

    Promit Mu-43 All-Pro

    Jun 6, 2011
    Baltimore, MD
    Promit Roy
    The meter appears in the lower right corner of your LCD/EVF when in full manual mode. It looks exactly the same as the exposure compensation scale, but shows what you're going to get relative to what the camera's light meter wants to get.
     
  5. Phil66

    Phil66 Mu-43 Regular

    130
    Dec 27, 2011
    Hmm,
    A lot of this is going over my head. I have taken a lot of pictures and have been pleased with the composition on my old Ixus, I bought a G3 to get better image quality. I am wondering if I have bitten off more than I can chew.

    Phil
     
  6. ean10775

    ean10775 Mu-43 All-Pro

    Jan 31, 2011
    Cleveland, Ohio
    Eric
    Don't be intimidated. It takes time to learn and understand all this stuff, but its definitely worthwhile and can make photography all that much more enjoyable when you start to see the improvement in your pictures. I think that the way Bryan Peterson wrote the book doesn't necessarily lend itself well to people who weren't brought up in the film era, but it does apply to digital photography as well. Read, re-read and experiment with the concepts he discusses - you'll get the hang of it and have an 'Aha!' moment or two. I'm still trying to get my sister-in-law to read the book so she stops calling me with the same questions regarding her camera settings over and over again. It really is the best book for understanding exposure, hence the title.
     
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  7. Squidz

    Squidz Mu-43 Regular

    38
    Feb 8, 2012
    Red Deer, Alberta
    I certainly agree with the above, don't get too worried, the patience and practice will be much worth your while.

    Which parts of the answers above aren't you quite getting a handle on, we'd all like to try and help you out.
     
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  8. Livnius

    Livnius Super Moderator

    Jul 7, 2011
    Melbourne. Australia
    Joe
    Don't throw in the towel just yet Phil.

    You may not realize it just yet...but you're a very lucky bloke. This is an amazing forum you've found and its home to some the most sensible, knowledgable and generous regular contributors I have found on any photography forum.

    Stick around, read as much as you can....but don't expect to get everything right away....that'll take time and yes, a a fair bit of extra curricular googling and reading books like B Petersons.
    Soon though, you'll find that pieces of the jigsaw puzzle begin falling into place.

    I know...I shot nothing but an ixus in full auto mode up until about 8 months ago and I also felt overwhelmed and a little lost when I picked up a GF1. But trust me.....in time it'll begin to click ;)

    Good luck....and welcome.
    Joe.
     
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  9. Phil66

    Phil66 Mu-43 Regular

    130
    Dec 27, 2011
    It's just, how do I do that what he talks about with the G3. Pointing at the sky I can do :rolleyes: but how to obtain and use the information the camera gives me is another ball game.

    Phil
     
  10. ean10775

    ean10775 Mu-43 All-Pro

    Jan 31, 2011
    Cleveland, Ohio
    Eric
    First, put your camera in manual mode (M). Now you will notice that the camera won't change any settings unless you set them. Pick an aperture - let's say f5.6. Now point your camera at the sky and adjust your shutter speed until the meter in the right hand corner of the screen (per Promit above) indicates that the exposure is correct (i.e., the little tick mark is in the center of the scale). Now your exposure should generally be correct for any subject provided the current lighting situation stays the same. Alternatively, I believe Bryan Peterson says you can meter off of the palm of your hand rather than the sky, but instead of zeroing out the meter in the center of the scale, you want it to show a 2/3 stop overexposure - typically two ticks to the right of center (provided your scale is set to 1/3 step increments)
     
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  11. I treat the automated systems in a camera like any piece of computer software. Learning the theory behind what it does is is useful up to a point, but I'm more interested in how the camera applies the theory for each given metering mode and what the end result is likely to be; essentially learning via feedback from the camera. That way, I can take full advantage of the automatic metering but also know under what circumstances I may need to intervene.

    The minutae of the theory behind exposure is not important to me.
     
  12. ~tc~

    ~tc~ Mu-43 Hall of Famer

    Oct 22, 2010
    Houston, TX
    IMHO, setting the camera in manual mode then zeroing out the meter is retarded. If you're going to do that, just set it in A or S mode ... Which brings me to the most important part of Understanding Exposure ...

    The interaction of ISO, aperture, and shutter speed, and their impact on the image is the critical element to pick up from this book. Is depth of field critical to your vision of the scene? Then you want to control the aperture. Is motion blur important? Then you want to control the shutter speed. Need a combination of the two, but can't get it? Then shifting ISO or using ND filters can do that.

    From there, you can get out and make creative images, and develop your style, going from there.
     
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  13. ean10775

    ean10775 Mu-43 All-Pro

    Jan 31, 2011
    Cleveland, Ohio
    Eric
    Its far from 'retarded', and the OP is trying to learn about metering and exposure from Bryan Peterson's book and this is how it is explained. The point of shooting in manual mode is that if you meter your camera correctly for your subject under a consistent light source your exposure shouldn't change and this will give you a series of consistent exposures regardless of how you compose and recompose your frame - if you use A or S mode the camera is going to change your exposure based on what else is in your scene when you recompose unless the scene as a whole averages out to 18% grey. Yes, there are plenty of times when A or S priority modes are useful and I use them a lot, but that's not what the OP was asking about.
     
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  14. Phil66

    Phil66 Mu-43 Regular

    130
    Dec 27, 2011
    Thanks that has helped quite a bit (from post 10 onwards). I last night downloaded 'The Panasonic Lumix DMC-G2' by Brian Matsumoto Ph.D to my Kindle, it isn't for my camera I know but I thought they were close enough to be of help. It really is, it explains everything much clearer. Thanks guys.
    Stickin at it ;o)
    Phil
     
  15. fljoe

    fljoe Mu-43 Regular

    101
    Dec 30, 2011
    FL
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  16. Phil66

    Phil66 Mu-43 Regular

    130
    Dec 27, 2011
    I kinda get the theory of it all, well as much as I can without the experience but it is appying it to my camera that is tricky for me at themoment. I'm sure that last book I have bought for my Kindle is going to really help.

    Cheers

    Phil
     
  17. mrmessy

    mrmessy Mu-43 Rookie

    15
    Mar 12, 2012
    I must confess that I have never taken a great interest in exposure (left it to the camera) in my old point and shoots. Now that I have a G3 I have been shooting RAW + JPEG and I have found a tendency for the G3 to underexpose. This is easily corrected in RAW and has an advantage in that blown highlights are less likely to be a problem. You could argue that one should get it right in the camera but RAW appears to tolerate a couple of stops at least under/overexposure.
     
  18. Brian Mosley

    Brian Mosley Administrator Emeritus

    Dec 15, 2009
    While this isn't a tutorial on exposure, I've found it a very useful piece on exposure compensation for the E-P3, E-PL3 and E-PM1... will be useful for the E-M5 too.

    Pekka Potka on Expose To The Right with the E-P3.

    Hope it's of interest.

    Brian
     
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