Project: Highlight clipping


My camera's  highlight clipping warning is always left on.I used some old teddies propped against a white textured wall for this exercise.


Exercise Highlight clipping
Using an aperture of F1.8 and ISO 200 the correct metered exposure was 1/40secs.The highlight clipping warning just appeared at 1/20secs.My five images were taken @ 1/20  1/15   1/25 1/30  and 1/40. At 1/15secs the overexposed white areas of the wall have become featureless and there is very visible loss of texture, however it has become, lighter, brighter, and much less grey looking .To retain the whiteness of the walls it would be necessary to overexpose but this is at the expense of the visual detail lost in the clipped highlight areas around the pink and white teddy's head. I can see that there is no definition between the whitish fur and background, it has been totally lost. The pink fur on the left hand side of the face has become so pale the colour is indistinguishable.

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@ 1/15 secs Highlight clipping indicated by the red areas.
Not really a problem for the white wall behind.


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But the close up of the bear demonstrates just how much detail is lost due to the highlights being clipped.

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As the images were shot in Raw I can attempt to recover this lost information using the Recovery slider in Lightroom. The more I increased the recovery slider the stranger the image looked to me. The tones looked somehow un-natural, I felt the whole image was degraded.

Trying to find an acceptable compromise to save the detail lost in the clipped areas I moved the slider about a third of the way across, this is not a perfect solution however the pink tones have now become visible again and some detail has been saved, but avoiding badly blown highlights in the first place is the best practice.


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 Compromise
 Recovery slider used to bring back some of the lost information.

What have I learned ?
The image as initially taken (see below) at first glance looks acceptable, I wanted the backlight to outline my subject  and was aware at the time the highlight clipping warning was flashing. As the tattooed  back was the intended main tone I was not too concerned if the sky detail became blown, it was not especially important for this image. However using what I  have learned from this exercise I looked closer at the clipped highlighted areas. The sky , hair and shoulder are all overexposed, but the area that suffers most is the skin area around the shoulder. Looking closely there is total loss of skin texture and detail , as well as a highly visible break where the highlights become featureless white. Additionally the fringed area at the edges of the clipping, before it becomes featureless white, is rather strange  to look at, its hard to describe but the texture looks mottled which in turn  creates a rather strange appearance to the surrounding tones. Prior to doing  the exercise although I was well aware to avoid highlight clipping in retrospect I was not really knowledgeble enough to consider and take into account just how detrimental this can be to the quality of an image. Luckily this image was shot in Raw format so I was able to process and recover some of the lost detail in Lightroom.  Assignment 2 has to be shot in jpeg format with no post-processing , I will need to careful to remember what I have discovered and ensure I evaluate what is important in the frame and try to ensure I capture the best  quality exposure I can. However even when shooting Raw using this knowledge will save valuable time by reducing any post- processing work needed, getting the best image in camera should be my aim.

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Original Raw image

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Clipped areas in red

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Shoulder shows loss of texture and detail

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Auto tone recovery @ 29%

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Recovery slider @ 100%

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Recovery slider @ 50%

Final image. 




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