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Evening,

Does anyone else take a picture underwater that they are pleased with but find that when they look at it on a monitor in a well lit room that it is grossly under exposed?

It happens to me all the time and I find myself pushing the exposure up in lightroom to compensate.

For example:


Original picture, looked correctly exposed on screen at the time.


Picture after being pushed +1.70 stops and +20 fill light. Now looks like how it did on screen at the time, note the extra noise.

So how do people get around this? Do you purposefully overexpose the picture knowing that you can bring it back later on? Do you just turn the brightness of the screen down?

For reference this shot was taken at 1/20sec, f/4.5 ISO400.

Cheers, Joe
 

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Im still underexposing about 90% of my photos underwater- look great on a screen down there, histogram looks "ok" but on a laptop they're rubbish.

Im also still struggling when reviewing in that the photos look too red, i turn down strobe to find they're bland and washed out on the surface.

Think i'll try turning screen brightness right down for the next dive.
 

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ISO down a tad.
Turning down ISO without changing anything else will certainly reduce exposure, however it's not really addressing the root of the problem.

The screens on the back emit their own light (some will also change the brightness of the screen automatically), the emitted light can make you think a picture is correctly exposed when it's not. Setting the screen brightness manually (I set mine just below middle brightness) and using the histogram to check your exposure levels can help you avoid being fooled by the image on the screen.
 

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Im still underexposing about 90% of my photos underwater- look great on a screen down there, histogram looks "ok" but on a laptop they're rubbish.
I'm curious...do you have an example of one where the histogram looked "ok", but turned out to be poor?

In general, under exposing by up to 1 stop isn't a bad thing and is a lot better than over exposing by the same amount.

Before I had my eye operations, I always had the screen turned up brightly so that I had a small chance of reading it, so I learned to trust the histogram. Now, I can read the screen again and I'm no longer guessing what I've done to the settings! Sadly, my shots aren't that much better :cry: :D

Cheers, Chris
 

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Histogram. Added benefit of the D200 histogram is it shows 3 channels plus White, so I can see how much the strobe is illuminating the scene. No red equals no strobe illumination.

Regards
 

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A lot, well, quite a few, people don't seem to understand the value of light in this equation. Screens, of whatever type, are backlit, they therefore give a false image, like it or not. That very much includes the monitor.

If you then set up your screen in a "well-lit room" you are exacerbating the problem because of that lighting. It is generally acknowledged that +/- 5000 kelvin is as close as you are going to get to daylight, as in a sunny day without sunlight directly affecting it. My Artroom, when I still ran one, had 5000 k lights, no shades or other disseminating materials (to change the value of the light) and heavy drapes permanently affixed to the windows. What we didn't need was extraneous light getting in, so the doors were also always shut. Of course the monitors were re-calibrated on a weekly basis (which got longer as the technology got better).

Light, the quality of it, can and will affect the outcome of a photograph (or video clip). Take a sheet of plain paper outside on a sunny day (without direct sunlight), look at it. Then take it outside again on an overcast day. You will, certainly should, notice a significant difference.
 
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