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We all know that the Moon provides natural light pollution, which is best to be avoided when taking pictures of the night sky. However, I am curious, can you still get good photos with the moon in the sky, if you are shooting nearby space objects like geostationary objects like satellites.

Note: I am using Nikon d3400.

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How much the Moon affects the ability to photograph other astronomical objects is highly variable based on many factors:

  • The phase of the Moon. A full moon washes out much more of the sky than a thin crescent.
  • The relative positions in the sky of the Moon and your target object. The closer in the sky the moon is to your target, the more pronounced the effect of the Moon's light.
  • The amount of water vapor and particulate matter in the atmosphere. The more things there are in the air that disperse the Moon's light, the greater the effect the Moon's light will have on your ability to separate your target's brightness from the brightness of the sky.
  • The altitude at which you are located. Higher altitudes have less of the densest parts of Earth's atmosphere, and all of the moisture and particulate that may be in it, between the camera and astronomical objects, so there's less of the Moon's light dispersed over the entire sky.
  • Atmospheric turbulence can make it more difficult to see dimmer astronomical objects.
  • The brightness of your target object. It's practically impossible to image a fourth magnitude object with a full moon anywhere in the sky. On the other hand, It's very easy to capture a very bright object, such as Venus which can be as bright as magnitude -4.7. In fact, at magnitude -4.7, Venus can be imaged when the Sun is in the sky. Just be careful not to point your lens so that the sun is in the frame or in the image circle projected by the lens but outside the frame.

Two example images:

A very thin crescent Moon and a few bright stars above the horizon shortly after sunset on 13 March, 2013. If one looks closely one can just make out Comet Pan-STARRS almost lost in the atmospheric haze closer to the horizon.

enter image description here For more details about this image, please see this answer to How can I capture earthshine?

An almost full Moon completely blows out and creates numerous flares and ghosts at exposure levels needed for much dimmer astronomical objects.

enter image description here
For fuller details about this image, please see this answer to Can you photograph the milky way with a full moon out?

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I wouldn't way it's the Moon the 'culprit' but rather the interaction between the sun light, passing by the Moon's surface, and, the most important, our atmosphere which is highly charged with suspended particles which diffract light and that make the sky polluted by light. That's precisely why it's blue during daylight and close to black at night time.
You can check this, this and this out for more detailed information.
The same phenomenons apply to the Moon light I guess.

And that's why the higher terrestrial optical instruments are placed (I'm mainly thinking of large telescopes, but this obviously applies to our digital cameras) in relation to the ground, the better the images.

Of course, this is valid if you make abstraction of any other sources of light such as urban lights.

That said, one of the best way to get rid of "random pollution" is to go for image stacking. There is many many softwares out there to post-process astronomical images... One that I like is DeepSkyStacker.

But as the first comment hereunder by scottbb says, indeed, is that you won't get rid of the part of the pollution which is based on the atmosphere physics and how light actually travels in this medium, which can be coarsely modeled because of the well known vertical composition of the atmosphere and hence, the global variations of the refraction coefficient for example.
The stacking will only get rid of stochastic or not predictable (and mostly small) perturbations, either the electromagnetic ones at the sensor level, or the environmental ones such as the atmospheric turbulence that affect astronomical observations, which also are the main cause of star twinkling and which led to the invention of adaptive optics for example. But I guess we won't have such nice technologies in our digital camera during our lifetime.

Finally and most of all, If you have to take away one thing; avoid the Moon, especially if the atmosphere is not perfectly clean such as after a large rainy meteorological event (because of the light diffraction). It is statistically worth waiting an average half a month to get good shots.

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    Good answer, but the sentence, one of the best ways tog et ride of “random pollution” is image stacking, is misleading. Light pollution in the sky is not random — it has a definite bias. Therefore no amount of image stacking will eliminate light pollution. – scottbb Apr 27 at 18:29
  • You are perfectly right, I didn't wanted to add more information on the predictable part of the atmospheric modelling and the stochastic one, mainly turbulence, which is a matter of 'at which scale' you are actually observing things, but it is indeed important to differentiate the two. – s.k Apr 27 at 18:54

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