User Tag List

Thanks useful information Thanks useful information:  0
Results 1 to 13 of 13

Thread: Exposure Lock

  1. #1
    Member Primal Eye's Avatar
    Join Date
    18 Aug 2010
    Location
    Bellevue Heights
    Posts
    5
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Exposure Lock

    Hey guys

    I'm new to this so I may well be miles off the correct technique, but I was hoping for some advice.

    I was trying to take a portrait shot last night at dusk. The sky behind the subject was incredible, and I wanted that exposed correctly. I aslo knew that I'd have to use my flash to light the subject.

    I turned off the flash, pointed the the lens at the sky, depressed the shutter button half way down to take an exposure reading from the sky, then recomposed the shot on the subject, and turned the flash on. Now here's my question: since the subject is alot closer to me than the sky should I have manually focused on the subject once more? Or is there a way to keep exposure lock active while refocusing on a subject that's closer, or further away than the area/item you have obtained your exposure lock from?

    Does that even make sense? Really enjoying playing with the exposure lock, makes for some really interesting shots - just not sure I fully understand what I'm doing to be honest.

    I have a Canon 50D

    Thanks

  2. #2
    Ausphotography Regular swifty's Avatar
    Join Date
    18 May 2007
    Location
    Singapore
    Posts
    1,352
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    You should have a dedicated exposure lock button, something like a AE-L button.
    Use that instead of the shutter half press.
    On Nikon models, half press usually only lock focus, not exposure but u may be able to configure it to lock both on your model. Check whether a half press locks both focus and exposure or just focus.

    But yea, you can AE-L background, recompose and AF lock subject with half press and take shot with flash.
    Or even simpler, go into manual mode. Adjust exposure for background only.
    Once you have it, you don't need to touch the exposure setting too much (sunset light changes quickly though). Turn on your flash and set to ttl, focus on your subject as normal and your flash with light your subject correctly. Use flash compensation to adjust how much you want your subject lit.
    Nikon FX

  3. #3
    Account Closed Wayne's Avatar
    Join Date
    07 Dec 2009
    Location
    Eastside
    Posts
    1,639
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Some Nikon bodies have an AF-L / AE-L combined button. It's default operation is to lock both focus and metering, but it can be programmed to lock just one or the other.

    You could use it in the default mode, by;
    Place focus mode in single servo and focus on subject > now compose to meter the sky (don't touch shutter button, so do it straight away before meters turn off) and while pointing at the sky, press and hold the AE-L / AF-L button > compose back to your subject ensuring your focus point falls on exactly same place as it did when you originally acquired focus, otherwise use manual focus (assumes AF-S lens for Nikon) to tweak it, then shoot away.

    My bodies (D3s & D800) have dedicated AF-ON buttons and I use them for focus, I have set the AE-L / AF-L button to lock meter only with a single press (no need to hold down - it resets after meters turn off or you fire camera) and can simply;

    Meter background>Press AE-L / AF-L button>compose and press AF-ON to focus then shoot.

    There are also function buttons on my bodies which can be programmed, and I know some who choose to use one of them for locking the meter only.

  4. #4
    Ausphotography Regular
    Join Date
    04 Aug 2011
    Location
    Sydney
    Posts
    793
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    I’d have used MANUAL Camera Mode.

    I would have made a Meter Reading of the Sky – and used FLASH EXPOSURE COMP for the FLASH as FILL.

    I would not have used Exposure Lock.

    To use Exposure Lock, it means one MUST be using an Automatic Camera Mode, such as: Av, Tv, P - and in those CAMERA MODES, one does not have (as easily) the full control over the Flash Fill: and in some situations one cannot have full control over the Flash as Fill.


    ***


    Also you are confusing "focusing on" (i.e. using Auto Focus) with making a Light Meter Reading by using the Half Depress Shutter Release position.

    You can separate these two functions by using “Back Button Focus” – i.e. setting the AF to the <AF-ON> button.
    The method of achieving this is in “CUSTOM FUNCTIONS” in your user manual –
    It is C.Fn IV-1, for a 50D.
    Selection 3 would be good to meter and lock, for the purpose of the shot you described.

    But as already mentioned, I wouldn’t do that for the shot you described: because I would be using Manual Camera Mode.








    WW

    - - - Updated - - -

    Canon User Manuals are sometimes “ho-hum” have a read of this:
    http://www.learn.usa.canon.com/resou..._article.shtml

    WW
    Last edited by William W; 21-09-2012 at 9:04am. Reason: Added the C.Fn

  5. #5
    Account Closed
    Join Date
    02 May 2012
    Location
    Namoi Valley
    Posts
    849
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    As William says. Manually meter the background, recompose and focus without touching the manual settings and use fill flash with flash exposure compensation according to need. If needed take as many shots as necessary to get the fill flash level you require.

  6. #6
    Member
    Threadstarter
    Primal Eye's Avatar
    Join Date
    18 Aug 2010
    Location
    Bellevue Heights
    Posts
    5
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thanks guys

    Some great advice, much appreciated - even if i don't understand it all fully .

    I'll have a go and see if I can use the manual mode.

  7. #7
    Ausphotography Regular
    Join Date
    04 Aug 2011
    Location
    Sydney
    Posts
    793
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Primal Eye View Post
    i don't understand it all fully
    What?

    WW

  8. #8
    In Training MarkChap's Avatar
    Join Date
    09 Jan 2008
    Location
    Widgee, Queensland
    Posts
    2,228
    Mentioned
    2 Post(s)
    Tagged
    0 Thread(s)
    Primal, yes the 50D has an exposure lock button.
    You have 3 buttons on the back, top right, near your thumb, from the right -
    Button 1 - Focus Point Selection
    Button 2 - Exposure Lock (symbolised with a star)
    Button 3 - Af- On

    So in your situation, provided you were shooting in Av, Tv, or P (won't work if green box auto), yes point at the sky -> depress the shutter button half way, this will both set the meter and auto focus, then whilst still point at the sky depress the middle button on the back top right, turn your flash back on, recompose your shot and depress the shutter button halfway to re-focus and then take your shot.

    In Av mode the canon system expects that you are using the flash as fill and will get your exposure pretty right for you.

    As mentioned, there are better different ways (shooting modes) to do the same thing.

    The advice by others above will work, but if being so pedantic as to say that you should have used manual, then you also should have had the flash off camera, and that is a whole new world of confusion for you.
    Your theory is correct, and with the use of exposure lock you will get some pleasing shots
    Smoke Alarms Save Lives, Install One Today
    I shoot Canon
    Cheers, Mark


  9. #9
    Administrator ricktas's Avatar
    Join Date
    24 Jun 2007
    Location
    Hobart
    Posts
    15,137
    Mentioned
    8 Post(s)
    Tagged
    1 Thread(s)
    Quote Originally Posted by William W View Post
    What?

    WW
    Remember you are dealing with a BEGINNER here.
    "It is one thing to make a picture of what a person looks like, it is another thing to make a portrait of who they are" - Paul Caponigro

    Constructive Critique of my photographs is always appreciated
    Nikon, etc!

    RICK
    My Photography

  10. #10
    Account Closed
    Join Date
    02 May 2012
    Location
    Namoi Valley
    Posts
    849
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by MarkChap View Post

    The advice by others above will work, but if being so pedantic as to say that you should have used manual, then you also should have had the flash off camera, and that is a whole new world of confusion for you.
    Your theory is correct, and with the use of exposure lock you will get some pleasing shots
    I can't see anyone saying he should have used anything, Mark, only "I'd have used manual mode". Personally and the reason I agreed with William, most certainly not for the purpose of an idealistic pedant regarding the manual operation of a camera but in my opinion, a simple and accurate method of achieving the particular exposure of both the sky and subject wanted by Primal.

  11. #11
    Ausphotography Regular
    Join Date
    09 Nov 2009
    Location
    Kalgoorlie
    Posts
    1,153
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Hi Primal,

    Another thing that may be worth mentioning, turn your speedlight to high speed sync setting. That way you will be able to use shutter speeds above 1/200 with the flash. That will help to get the background sky well exposed, and not overexposed, while still allowing the flash to be used.

  12. #12
    Ausphotography Regular
    Join Date
    04 Aug 2011
    Location
    Sydney
    Posts
    793
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by ricktas View Post
    Remember you are dealing with a BEGINNER here.
    I was specifically remembering that this is a BEGINNER'S Forum.

    The OP stated that not everything was understood.
    I asked "what (was not understood?)” – so that I (and others) might have a better opportunity to explain those particular areas in depth.

    My question: "What?" - pertains specifically to the quote of the OP's which I referenced and that’s why I referenced that particular quote.

    It occurs to me that you have misinterpretted the meaning of the question, beacuse of the brevity of the response.

    WW

    - - - Updated - - -

    Quote Originally Posted by norwest View Post
    I can't see anyone saying he should have used anything, Mark, only "I'd have used manual mode".
    Yes.

    And that's exactly why it was written that way - because I would have used Manual Mode and I was offering that as another option to the OP to doi the job as described.

    Note the question of how to use Exposure Lock was answered in detail, also . . . without having to turn the Flash On and Off.


    WW

    - - - Updated - - -

    Quote Originally Posted by fess67 View Post
    turn your speedlight to high speed sync setting. That way you will be able to use shutter speeds above 1/200 with the flash. That will help to get the background sky well exposed, and not overexposed, while still allowing the flash to be used.
    If you use HSS, you'll need to watch out for WD (Working Distance - how far the Flash is located, away from the Subject).

    In simple terms, usning HSS robs the Flash of Effective Power and LESSENS the MAXIMUM working distance from the Subject.

    So it is a balance - using HSS means you can use fast Shutter Speeds, but the Flash might have to be located closer to the Subject.

    WW

  13. #13
    Member dodgyexposure's Avatar
    Join Date
    12 Jul 2012
    Location
    Brisbane
    Posts
    18
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    If OP is truly a beginner, then using fill flash in Av, and evaluative metering will probably obtain a usable result, because the camera is likely to predominantly meter for the background anyway.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •