BBC Sky at Night - UK (2021-08)

ASTROPHOTOGRAPHY

PROCESSING

Expert processing tips to enhance your astrophotos

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78 BBC Sky at Night Magazine August 2021

M

y winning entry in the

‘Stars and Nebulae’

category at the

2020 Astronomer

Photographer of the

Year competition is

entitled ‘Cosmic Inferno’. It features the

emission nebula NGC 3576, one the most

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of ionised gas that stretch over 100

lightyears into the vacuum of space.

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polycyclic aromatic hydrocarbons within

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hydrogen-alpha (Ha) data to enhance the

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that engulfed much of southeastern

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effect on my attempts to capture any

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shrouding not just my small observatory,

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around it; indeed, NASA satellite data

later showed the aerosols completed an

entire circuit of Earth.

With attempts to capture colour data

thwarted, my attention was focused on

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managed to acquire. Mid-evening news

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were uncannily similar to my Ha data. In

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To begin, I calibrated the RAW image

Advice from a winning

entrant in the ‘Stars

and Nebulae’ category

APY Masterclass

Bring out a nebula’s fiery features

Use stacking software and a ‘bushfire’ colour palette to enrich detail

NGC 3576, hydrocarbons being an essential

component for the formation of the earliest

life on Earth. And 3.7 billion years after life

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across vast swathes of the Australian

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the title I gave to the image.

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image of NGC 3576 using my Alluna RC16

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colour image requires red, green and blue

‘Cosmic Inferno’: the impactful

image of emission nebula NGC

3576, with its distinctive ‘Statue

of Liberty’ feature clearly visible

Þ The RAW image is calibrated to reduce

unwanted artefacts and shadows