• 05-17-2005, 05:58 PM
    stuntboy
    falling moon...need assistance
    tried this night photography of the moon. can someone explain why the moon is shadowed like this. the moon is the bright flash in the top center of the photo.
    http://www.ourpics.ca/falling_moon_900.jpg

    thank you
    todd
  • 05-17-2005, 07:23 PM
    Dzerzhinski46
    Re: falling moon...need assistance
    My first thought is that you overexposed the moon. Any bright object will flare out in that star pattern if overexposed. Now, what is that small cresent in the lower part of the picture? As the moon is only just half full, the lower object looks a bit like the moon. Please enlighten.

    Drew
  • 05-17-2005, 07:43 PM
    stuntboy
    Re: falling moon...need assistance
    Drew that is the half moon shadowing itself from the bright flare in the top center of the picture. that was the original question...sorry if i wasnt clear enough.

    http://ourpics.ca/falling_moon_explained.jpg

    todd
  • 05-17-2005, 08:53 PM
    Chunk
    Re: falling moon...need assistance
    I think its a reflection on one of the glass surfaces in your lens or filter if you have one on.
  • 05-17-2005, 10:31 PM
    drg
    Re: falling moon...need assistance
    I'd agree with Chunk on first examination except for a couple of things:

    The shape of the 'moon artifact' is considerably different than the original. It is too sharp compared to the moon as well and does not display similar levels of radiance.

    Also its apparent or observed magnitude, at least in this image, doesn't seem to be significantly different enough to be the typical lens aberration or internal reflection and most lenses I don't believe would put the aberration in that place. Admittedly some of the newer zooms have some crazy optic properties when pushed, but ....

    From the magnitude(intensity) of the stars and the brightness of the chimney in this photo it looks like the shutter was open a significant length of time. Seconds perhaps?

    From all this I'm wondering if you caught a stray reflection of a car headlight off a cloud or some other fairly high intensity light that just happens to look moon like. And the chimney may be the culprit. For a night shot, the metal is showing a pretty high amount of reflection from some light source. It may even have caused that half/quarter moon reflection as a result of some unexpected angle of incidence from one of its curved surfaces.
  • 05-17-2005, 11:33 PM
    jar_e
    Re: falling moon...need assistance
    Just a thought, in BC, the moon is a half moon the either way (blank on the left, half on the right), and I don't think it changes throughout Canada, so I don't think it's the moon. Unless of course it is a polarizer filter or something that flipped the picture around. Or it may be a type of lens flare from what not. It's interesting to say the least,

    Jared
  • 05-18-2005, 05:56 AM
    Chunk
    Re: falling moon...need assistance
    Shape depends on time of day and day of lunar month. If it's a rising moon it's going to look opposite of a setting moon. If it's a waxing moon it will look opposite of a waning moon. If it's a reflected moon, it'll appear to be opposite the straigh shot.