Pleiades (7 Sisters), M45

Mar 2021

Imaging: ST120 achro, Canon 1000D 400ISO, no filter & L-Pro
Subs: 182x120s NOFILTER + 103x120s L-Pro (9.5h), bias, darks, and flats
Processing: PixInsight

(Additional notes below)

Gallery

Notes

It is now galaxy season for astro photography. Unfortunately, all the available ones are either north or east where I have no visibility. Those will have to wait until later in April. Without anything to image, I decided to make my third attempt at the Pleiades, commonly known as the Seven Sisters. According to Wikipedia, the Pleiades is an open star cluster containing middle-aged, hot B-type stars in the constellation Taurus. It is among the nearest star clusters to Earth, and it is obvious to the naked eye. The blue nebulosity makes it one of the more recognized images of the night sky.

I was hoping to capture the full nebulosity as I did it "right" this time with proper centering, guiding, many more hours of imaging, and full processing in PixInsight. I started imaging without any filter as this is a broadband target. I got about 6h of data this way but I had a lot of trouble with gradients. I then collected an additional 3h of data using the L-Pro filter to see how much of an effect that would have. It was unclear whether this would help or hurt; some experienced imagers claim it is totally wrong for this type of target. In the end, I didn't see a significant difference between using no filter and using the L-Pro on this target.

This is another image that would be considered subpar in the astrophotography community. As this was taken with my old achromat, it exhibits the same bad blue haloing of the stars.