Avoiding the Moon
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Our online training has a comprehensive course that gives further details about how to find out if the Moon could affect your images.
Days around Full Moon (Bright Time)
This is quite possibly one of the most important things to take account of when planning your observing sessions. For a number of days each month the Moon is in a phase where it is either full or very nearly full. This can have serious implications for the type of observing you may want to do.
The images below show one of the effects of moonlight on an image taken with a Faulkes Telescope. The images are colour composites taken with red, green and blue (BVR).
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You can see from the image that there is less contrast than you would perhaps like and the image appears to have a blue border around it. This is not really a very acceptable image. However, it is always worth looking at what can be achieved in each waveband in case there is the possibility that imaging in a different part of the electromagnetic spectrum is any better. The three images below show the three images that the colour image above was made from. Please note that the images are shown in greyscale as the telescope camera only records brightness in each colour channel not the colour itself.
Immediately you can see a number of useful things. The blue image clearly has a very light border which would explain the blue borders in the colour image. It also contains very little detail in the galaxy. The green filter is better but it has less of a bright border (although there is still one present) and has more galaxy details. The red image is the best. There is no border that is visible and there is much more detail in terms of number of stars and the structure of the galaxy. In this case it is clear that blue is most affected by moonlight as it "washes out" the detail, green is next most affected and red is affected the least.
From this example, it is clear that when imaging faint objects when moonlight may be a problem, the red filter is the best to use as it is affected less by moonlight.
