Friday, October 27, 2006

Night time paddling


Well the clocks go back this weekend, bringing darker evening once again. No doubt we will have a few more night time epic returns as winter paddles run out of daylight. At least I had a nice full moon to illuminate my return on this solo paddle on the Solway.

3 comments:

  1. Oh come now, Douglas ...

    Mark R

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  2. Hi Mark,

    whole issues of photo mags have been devoted to photographing harvest moons. The difficulty is capturing detail in the scene, which is bathed in soft moonlight while correctly exposing the Moon which is in the harsh glare of full sunlight.

    You really have to make two separate exposures then blend them. Another problem is that standard and wide angle lenses make the harvest Moon look like a tiny dot, definitely not as you remember it.

    A telephoto lens will increase the size of the Moon's image but due to its shallow depth of field, especially in low light, you will not get a nice sharp foreground and Moon.

    In this case I made two exposures using a tripod. The foreground was made with a 24mm lens at f4 1/8 sec ISO 1600.

    I then played the image back on the screen and marked the position of the moon with a wax pencil.
    I then switched to a 300mm telephoto and took some practice shots to get the moon in the right place.

    I then exposed the top half with the 300mm lens f8 1/200 ISO200.

    If I have done my sums right, the foreground got 10 stops (times) more exposure than the Moon!

    Later in Photoshop I blended the two shots using a layer mask.

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  3. Meant to say, 10 stops is equivalent to just over a 1000 fold difference in exposure. No wonder neither film nor image sensors can cope with that difference.

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