Narrowband exposures during full moon?

Common “knowledge” says that one can do narrowband exposures (HAlpha, Oiii) during full moons. I don’t know why that should be OK, since the Moon is scattering HAlpha light from the Sun as well as the usual RGB.

So, I did some exposures during full Moon, and some during no Moon. Here are the results. These are single raw images, with a Screen Transfer function applied in Pixinsight so we can see the image.

Click on an image to see the full image.

HAlpha with Full Moon

HAlpha with Full Moon

HAlpha with No Moon

HAlpha with No Moon

The Full Moon image in HAlpha has a lot of extra blur/nebulosity, while the image without the moon shows significantly better detail and contrast.

OIII with Full Moon

OIII with Full Moon

Not much shows up in the OIII images; apparently the California Nebula doesn’t emit much in the OIII range. The full moon version has a serious gradient, could be a function of where it was in the sky. The No Moon version has better contrast around the two stars.

Conclusion: it looks to me like the Full Moon still has a significant impact on the narrow band images.

OIII with no Moon

OIII with no Moon


One comment on “Narrowband exposures during full moon?

  1. Pingback: Moon Effect on images | BrewSky Observatory

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