If the shot looks really bright, check for areas of pure white. If these exist,
then the shot is over-exposed and needs to be done on a faster shutter
speed and/or lower ISO. Many cameras can show over-exposed areas on
their rear displays. If you’re not sure what your model can do, check the
cameras user manual.
Deliberate Over-Exposure
When the Moon is a thin crescent, it’s sometimes possible to see the
dark, unlit portion glowing slightly against a background twilight sky, a
phenomenon that when seen in an evening twilight sky is called "the old
Moon in the young Moon’s arms". The cause of the dim glow is the Earth.
If you were to stand on the Moon’s unlit surface at such times and look
up in the sky, there you’d see the Earth at a near-full phase, shining down
on you with reflected light from the Sun. This light would illuminate your
surroundings in a similar manner to how the edge is taken off the darkness
of night when the full Moon is visible on Earth. It’s this gentle illumination that
makes the unlit portion of the Moon appear to glow.
The effect is called "Earthshine" and is best caught on camera by using
longer exposures which will cause the Moon’s crescent to over-expose.
For fixed-tripod shots, an exposure of a few seconds can, depending on the
focal length of the lens you’re using, introduce motion blur. Upping the ISO
should allow you to capture Earthshine while keeping the exposure times
to manageable levels. Done well, an Earthshine shot will render the dimly lit
portion of the Moon like the surface of the full Moon, full of lunar detail.
1110Our friendly Moon
Moon Colour
The Moon generally doesn’t look colourful in most images. However, there is
subtle colour to be seen on its surface, and amazingly, once the colours have
been unlocked, they reveal some interesting scientific information about
various features on the lunar surface.
A correctly exposed shot of the Moon’s disc taken with a colour camera
will contain this subtle information and it’s possible to tease it out using
a layer-based graphics editor. Load the image and then duplicate it as a53