Quote:
Originally Posted by PCH
, I've seen pics in magazines etc where there may be some other detail visible in such a picture, - like a land horizon, or stars in the sky etc - you know the sort of thing. And still with lunar details showing. Any thoughts on how this might be done as clearly a very fast shutter will not pic up non-lunar detail like this?
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A few ways - if it is shortly before or after sunup/down and the moon in low on the horizon, then often the brightness of the horizon and the moon will be similar, so the photo will show both. After all, if it is a full moon (and by definition the moon must then be opposite the sun from the earth) and it is just before sunset, then teh sun is shining both on the horizon and the moon. Allowing for atmospheric losses and albido, then their brighnesses should be about the same.
As for stars - remember a star is a sun and so the 'surface' brightness of a star -even if it is a point - is the same as the sun. So even a 1/10000 sec exposure will show something. If you think about it, a true point source will not show up on a perfect imaging device as the image formed will be infintesimally small. However due to atmospheric distortions, interference, lens aberations and imperfect imaging sensors - both film and digital both have a finite pixel size - the star image is far larger - infinitely I suppose - than what it should be. Anyway, even a relativly short exposure - 1/1000 of a sec will show up some stars.
The other way is to cheat a bit - overexpose for the moon, then in Photoshop or whatever, darken the moon and lighten the stars. Or combine two images - one with the moon correctly exposed and the other with - no moon.