Scene Dynamic Range

Scene 1 – A Full Moon  I’ve taken the opportunity of a full moon to start this exercise, my thinking being that I have a very bright light in the moon and very dark areas in the sky.

Spot metered from the moon 1/80 sec at f6.3

To an extent I go the results that I expected in that when I measured the exposure directly from the moon when the sky was perfectly clear, I got a fast shutter speed, 1/80 sec at f6.3 and when I measured directly off the sky, it was much slower.

Metered from the sky with moon in viewfinder 1/15 sec at f6.3

It wasn’t quite a simple as that though because if I measured from the sky when the moon was in the viewfinder the shutter speed was much faster than if I chose a spot away from the moon altogether.

Metered fron the moon but with cloud distorting the exposure 1 sec at f6.3

Furthermore if there was any cloud moving across the moon when the shutter fired, this completely changed the exposure.  All of the above I can understand but I also had one very strange result which I can’t explain.

Spot metered from the sky 1.6 secs at f6.3

I had the moon in the view finder but measured for a dark area of the sky and have two images of the moon in the picture.  In this particular case the shutter speed was very slow; 1.6 secs and whilst one moon is very over exposed the other is underexposed and blue.  I have asked this question on the OCA student site and ephotozine,  I’m sure someone will have the answer.

In each of the above cases I had the camera set to manual and with the aperture at f6.3 and adjusted the shutter speed to give the correct exposure for the spot  I was metering from.  Images were taken in RAW which showed that either the highlights completely blown out when I metered from the sky, or the shadows clipped when I metered from the moon.  I’m not entirely sure what I have learned from this, the range of lighting in the scene was very extreme but the important thing here must be to get detail in the moon so spot metering from the moon must be the correct approach.



About Anne Bryson

I live in Gloucestershire with my husband Iain and West Highland Terrier, Isla. I enjoy golf, photography and my grandchildren, not necessarily in that order! Having completed a 10 week digital photography course with the Open University in 2010 and wanting to take photography further, I enrolled on the Open College of the Arts BA (Hons) starting with 'The Art of Photography' which I thoroughly enjoyed. Next came Digital Photographic Practice followed by People and Place. In April 2016 I progressed to level two with Documentary and in June 2018 enrolled on my latest OCA course, Landscape.
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