These images of the willow tree in our garden were taken into the setting sun, to provide a high contrast image to demonstrate highlight clipping. The camera was hand held and set to aperture priority at f/4.2, to enable high shutter speeds due to the windy conditions. I used 7-frame bracketing with steps of 1 stop – two of the increased exposure images were later deleted.
The screenshots are of the image in Lightroom with the highlight clipping shown in red.
At 1/1600 sec shutter speed, the setting sun caused some highlight clipping. As will be seen in subsequent images, this was the threshold at which highlight clipping could be seen.
Close inspection shows a blue colour cast in the small branches and twigs in the clipped area.
Increasing the exposure with a shutter speed of 1/800 sec caused much more highlight clipping.
Details in the tree are more easily seen in this image.
Colours at this exposure are brighter – the farmhouse rooftops show to be redder, but the highlights in the sky have been severely clipped with the loss of any detail in this area.
The blue colouring of the smaller branches and twigs in the clipped area has become more pronounced and red chromatic aberration can be seen on the outlines of the trunk and larger branches
Reducing the exposure by one stop from the first image, with a shutter speed of 1/3200 sec has reduced the highlight clipping to just this tiny spot which could not be seen on the camera screen.
The sky now has more colours (more saturated) but obviously not as bright. Detail in the shadow areas is diminishing significantly.
The red aberration and the blue cast on the smaller branches and twigs have reduced, but it’s still there.
Reducing the exposure another stop, with a shutter speed of 1/6400 sec has removed all highlight clipping.
The sky is much darker but has more colours again. Shadows areas at the bottom of the frame have lost nearly all their detail.
The blue cast and red aberration can still be seen on close inspection.
With the shutter speed at 1/8000 sec the exposure is reduced to -3 stops.
At this exposure the day looks more like twilight.
The colours in the sky now seem to getting darker but not any more saturated than in the previous image. Maybe I’ve reached the saturation limit for this image.
Looking at the shadow clipping picture, above, the amount of detail that has been lost in the dark areas is really significant. The outlines of the farmhouse and vehicles cannot be discerned here.
The blue cast has almost disappeared and the red aberration has gone completely.
Looking again at the images in Lightroom, the over exposed image gives more detail and using 100% highlight recovery, with 10% fill light reduces the clipping while giving better sky colours and more detail in the tree / farm buildings. I think the overall image is quite flat, which could be improved by further processing, but I think that’s beyond the remit of this exercise.
So what have I seen?
· Reducing the exposure reduces highlight clipping, reduces chromatic aberration, loses detail in the shadows, increases the colour saturation (to a limit)
· Increasing the exposure has the opposite effect of above, but increases the brightness.
· I was unable to discern any distinct break between nearly white – total white in these images. Maybe it’s down to the image used – some white clouds may have worked better.
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