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Flash looking too obvious when scene is not "aligned"

Discussion in 'Tips and Techniques' started by Pyndle, Dec 12, 2019.

  1. Pyndle

    Pyndle Angel Fish

    # of Dives: 200 - 499
    Location: US
    65
    13
    8
    Hi all,

    I have a problem when shooting coral that is not evenly spread in front of me at the same distance. I know it's very obvious but the close objects are bright and colorful and what's in the distance is dark and grey (see examples below).

    I happens a lot when wall diving, unless you position yourself right in front of the wall.

    Is there a way to attenuate this with flash positioning / editing or is it just the way it is? There are rare cases (see last picture in my post) where I find the effect okay, because it makes one distinct bloc/object stand out.

    Any tip is welcomed :)

    Thanks!

    6fedcf5eb7866ca561a8995bb3181ad2ef7686b4.jpg

    6ffe85b0f3f22d9c877e92194bfa84f2f37bba8b.jpg

    5f386956111887f89f5785114795053bf5f2fbe2.jpg

    24f79f5d3cc46e2030ed9c648468da37fa4c9b68.jpg
     
  2. Gene

    Gene Dive Shop

    # of Dives: 500 - 999
    Location: Florida
    82
    61
    18
    You could have a diver holding a second slaved strobe closer to the background, and/or place another strobe there, hidden or just out of camera frame. We do this a lot in our Florida caves.
     
  3. tursiops

    tursiops Marine Scientist and Master Instructor ScubaBoard Supporter

    # of Dives: 2,500 - 4,999
    Location: U.S. East Coast
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    It is an inevitable effect of the inverse square fall-off of light with distance. Something twice as far away gets one-quarter the light.

    Solutions?
    (a) Two strobes...one pointed at the nearby stuff on low intensity, one pointed past the near stuff right at the far stuff, with higher intensity.
    (b) Angling a single strobe so it is just the edge of the light beam grazing the near stuff, but mostly pointed at the far stuff.
    (c) Composing the shot on the wall to look up rather than horizontally, so you get some sky and silhouette filling much of the frame rather than just blue-green coral off in the distance.
    (d) Shooting RAW, and composing so the more distant parts of the image can be color-balanced in post as if they are shot using ambient light...because they are.
    (e) Shooting with ambient light only, and color-balancing in post.
     
    Joe Weaver and Johnoly like this.
  4. Pyndle

    Pyndle Angel Fish

    # of Dives: 200 - 499
    Location: US
    65
    13
    8
    Thanks for the feedback guys! I'm gonna try that different intensity strobe setup and see how it goes :)

    What do you mean by d) tursiops? I always shoot raw, but not sure what you mean by "composing so the more distant parts of the image can be color balanced in post"?
     
    Johnoly likes this.
  5. Johnoly

    Johnoly ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: 2,500 - 4,999
    Location:
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    Along with powering DOWN the strobe, I also try to push my F-stop to 6.3 or 7.2 if possible. And to get the vivid way back colors move the ISO to 100 and a speed of 160. Also switch your auto focus to 'spot' to more accurately measure what's directly infront of you. But in the end it really comes down to how much ambient light and good viz you have. Garbage in results in Garbage out (unless you spend hours in photoshop)
     
  6. Chris Ross

    Chris Ross Manta Ray

    # of Dives: 200 - 499
    Location: Sydney Australia
    572
    187
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    you can only get colour where your strobe light can reach, so distant stuff is always going to be blue green, but you can influence what shade of blue green that is and how bright/dark it is. You can also influence the composition so that the subject fills the frame and the blue/green BG fits into the composition and doesn't pull your eye - generally getting closer to your subject and keeping the blue -green parts of BG smaller in frame.

    If you use a warming diffuser on your strobe the Auto WB will push you to a cooler/blue colour balance to make your flashed subject neutral - this means the BG ambient light will be a richer blue. You can increase your shutter speed (if you are not running up against the Sony 1/160 sync limit ) or lower ISO and increase flash power to make the BG darker which will help the subject stand out better against the BG.

    On your existing shots a levels colour balance will improve the BG blues - generally adding some magenta to the blues (removing green) will make the blues look better. This literally takes 1-2 minutes or less and involves a levels layer adjusted in each channel pulling in the shadows and highlights poiters to the edge of the histogram in each channel.

    A couple of examples:
    this one is shallow on a reeftop, BG is a thin band of blue green coral then blue water: http://homepages.ihug.com.au/~chrisx2/images/LalouReefScene8.jpg

    this one is deeper on a wall , the BG has gone dark or is blue water/schooling fish: http://homepages.ihug.com.au/~chrisx2/images/LalouReefScene2.jpg
     
  7. tursiops

    tursiops Marine Scientist and Master Instructor ScubaBoard Supporter

    # of Dives: 2,500 - 4,999
    Location: U.S. East Coast
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    What I mean is composing so that the part you want to color-adjust is all together, preferably with a roughly straight edge against the part your flash has exposed. Then It is easy to use the graduated filter to mark off a section to adjust. Otherwise, you spend a lot of time.
     
  8. Pyndle

    Pyndle Angel Fish

    # of Dives: 200 - 499
    Location: US
    65
    13
    8
    Thanks for the replies, it makes sense.

    Composition isn't always easy, if I take your example Chris Ross the gradient between the blue zone and the grey part of the coral is a bit obvious and that's the kind of things I want to avoid. But I guess it's either having a composition with a straight edge that separates subject from blue background (like
    tursiops suggested) or spending a lot of time adjusting colors with another gradient :(

    I thought maybe there was some obvious tip that I've missed or something :)

    Thanks for the help!
     
  9. Chris Ross

    Chris Ross Manta Ray

    # of Dives: 200 - 499
    Location: Sydney Australia
    572
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    43
    I think the point I was making was that the portion of the frame receiving light from the flash was quite large in comparison to the blue bit and unless you restrict yourself to compositions that really avoid including any distant coral in the frame it's probably as good as you can do without compromising something else. On the example frame I provided I could have dropped lower and the blue/green strip would be less but at the cost of reducing the size of the big coral in the frame.

    I don't think a gradient is the answer because if you adjust that colour you will probably also adjust the water colour as well and that means adding red/yellow to the blues/cyans which just makes them go muddy. It's not so much a straight edge as only having blue water behind your subject.
     

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