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Why did I get a reflection in the second picture?

Discussion in 'Travel Photography' started by Mattecube, Jan 10, 2019 at 6:00 PM.

  1. Mattecube
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    Mattecube Glad i did it Trusted Member

  2. oss
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    oss Not Here

    You were behind glass the first picture has a reasonable amount of light in the area where the internal light meter would read the sensor usually an area near the middle.

    Because it was looking at a lot of light (relatively speaking) the camera either narrowed the aperture of the lens or shortened the shutter speed or both.

    The second scene is mostly black in the middle so the camera would have tried to over expose the shot i.e. a wider aperture or longer shutter opening or again possibly both depending on the mode.

    What's happened is that the gallery you were in had some light a fixed amount of light, in the first shot the faster exposure could not see that reflected light clearly but in the second shot the reflected light was closer to the same exposure as the scene as the exposure was longer therefore the light showed up.

    You can see some hints of reflection in the first shot in the water to the lower left but it is not bright enough to swamp the main shot, the first shot is also sharper because of the shorter shutter speed, the second shot has a hint of motion blur because of the longer exposure and obviously the longer exposure means it captures more of the reflection.

    It is also possible that the effect is made worse by the location of the source of light in the gallery you were in, In the first shot the light source might have been off to one side but in the second it might be directly behind you.

    Other issues can be polarisation effects of the glass resulting is a greater reflection, but to be honest it looks like there was simply more light behind you in the second shot and the black water caused the camera to go for a slow shutter which caused a bit of blur and let too much light into the lens.

    Had I been taking it my camera would have been on manual as both shots need to be exposed for the lights and sky which are fixed brightness in both shots so the exposure settings for both shots should have been identical. I would have shot with a wide open aperture and as short a shutter speed as I could get away with on M, setting both these values myself.

    Ultimately the reason this happens is the same reason you can't see stars when you are standing on the moon in broad daylight, you can't see stars on Earth during the day because the pupil of your eye is small just like the aperture of the camera lens in your first short was probably narrower, daylight is just as bright on the Moon as it is on Earth.

    However if it were coming up to lunar night-time your eyes would adjust and you would see stars because your pupil would be wide like in your second shot where the camera made its pupil (aperture) wide.

    In both the case of standing on the Earth or standing on the Moon the day is just as bright and photos would have exactly the same exposure.

    Likewise in your photo the brightness of the scene the amount to which it is lit is actually the same and the exposure should be exactly the same for both of your pictures.

    The problem is the camera isn't clever enough to realise that and just sees the big black bit in the middle of the second shot and tries to change the exposure to compensate for the dark middle bit.
    Last edited: Jan 10, 2019 at 6:38 PM
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  3. Mattecube
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    Mattecube Glad i did it Trusted Member

    Thanks will take me a while to work through what you have said but I think I follow
  4. Mattecube
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    Mattecube Glad i did it Trusted Member

    oops lol OOPS.JPG

    How should I of shot this scene?
  5. oss
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    oss Not Here

    I reckon you rotated to the left by about 60-80 degrees, going by the dock on the right hand side of the second image.

    And I can see that the sky is about 1 stop brighter in the second shot, a stop is a technical term it's the difference between 1/125th of a second and 1/250th of a second or the difference between aperture f2 and f2.8.

    A 2 stop difference would be 1/125th of a second to 1/500th of a second. or f2 to f4.

    1 stop is a fair bit of light that plus the light that was behind you caused this.
  6. Mattecube
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    Mattecube Glad i did it Trusted Member

    Your right but it was probably a few minutes between the two.
  7. oss
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    oss Not Here

    Straight into the sun, the camera is trying to make the sun as dark as it can but of course no camera could make the sun dark so it fails, but as a result it makes everything else dark.

    It's actually done a reasonable job here it could have made the image almost totally black.

    There is no camera in existence that can cope with the dynamic range you have in that shot although some will do a bit better.

    If you were closer to your subject you could have turned on your built in flash gun and that would have helped light the subject but again this is a candidate for a manual shot where you set the exposure for the subject and let the sun blow out.

    On your camera you might be able to do a +3 stop adjustment in other words tell the camera to make the exposure 3 stops longer or 3 stops brighter but it still would not have been great.
  8. oss
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    oss Not Here

    Here's a similar example I took about 15 years ago, sun straight ahead and I'm going to lose the foreground.

    To retain the foreground I did two things, I used a powerful flashgun to get detail in the rock and I adjusted the exposure to let the sun blow out although I wanted it not too blown out.

    I also post processed the raw files using my digital tools to adjust the dynamic range.

    [​IMG]
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  9. oss
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    oss Not Here

    And this is what happens when you shoot straight into the sun and actually try to make the sun dark :D my subject was the Sun :D (Loch Fyne)

    This was taken on Kodachrome slide flim.

    [​IMG]
  10. oss
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    oss Not Here

    And this one in Malate on Roxas Boulevard only works because of atmospheric pollution and water vapour attenuating the sun to the point where you can actually look at it.

    [​IMG]

    edit:

    Same as this one which I took last May in Nasugbu Batangas, this only works because of pollution and clouds.

    [​IMG]
  11. Mattecube
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    Mattecube Glad i did it Trusted Member

    proud.JPG

    I think I did ok with this one
  12. bigmac
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    bigmac Well-Known Member Trusted Member

    or the window was open for the top photo
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  13. HaloHalo
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    HaloHalo Administrator Staff Member

    I wish I knew even the basics of photography. I actually downloaded the free software DaVinci Resolve 15 just last week. It’s an amazing piece of kit. The reason for downloading is that I got a new toy for Christmas. I’ve had a small play around with the software but not even scratched the surface of colour grading. I have done the lazy thing now and downloaded some LUT’s for grading the LOG output images.
  14. Mattecube
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    Mattecube Glad i did it Trusted Member

    Not 100 floors up lol
  15. bigmac
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    bigmac Well-Known Member Trusted Member

    just joking. i think in the top pic you were at an angle to the window--so didnt get a reflection--in the lower pic you were at right angles to the glass--so a reflection was inevitable.
  16. oss
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    Yes in terms of composition the first shot of the docks and this one of the bridge are quite good.

    From a technical perspective unfortunately the software you are using has stripped all the image data and they are quite small so I can't give a proper technical opinion but I would have been happy taking either of those two shots.
  17. oss
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    I had a go at cropping and making some adjustments but to remove the reflections needs a lot of surgery and the version you posted is not quite up to being adjusted that much, here's the result anyway.

    upload_2019-1-11_0-17-46.png
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  18. oss
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    Another attempt at adjustment in post, I think your lens might have had some condensation either in or on it due to the cold, the camera also appears to have hunted for focus and failed because of the bright sun and looks like the shutter fired while it focused far too close.

    upload_2019-1-11_0-21-59.png
  19. Dave_E
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    Dave_E Well-Known Member Trusted Member

    You turned the lights off for the first photo.

    Do I win the prize?

    :D
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  20. Mattecube
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    Mattecube Glad i did it Trusted Member

    Only in the daft comment section!
    I9
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