
The Lagoon Nebula
in Narrowband Mapped Colour


Description
The Lagoon Nebulae is one of the brightest nebulae in the night sky, and the brightest in this area of the night sky, making it popular amongst amateur astronomers and astrophotographers. It is a region undergoing star formation as large clouds of gas and dust coalesce under gravity to form newborn stars.
These are 2 images of the Lagoon Nebula, shot with different cameras and varying focal lengths, showing both the surrounding area (top image) alongside a more detailed, higher resolution view (bottom).
In these images of the Lagoon Nebula, the object is represented in a different light as opposed its usual true colour depictions. Instead of the usual RGB method of obtaining true colours of deep sky objects, the image featured here is an emission-line filtered image which represents the nebula's chemical composition. In this case, the nebula is photographed using a modified version of what is known as the Hubble palette, in which three filters to isolate Sulfur, Hydrogen and Oxygen emissions are used. The data from these three filters are then mapped to Red, Green and Blue respectively to create a false colour composite as depicted above.
This object was photographed from a city centre with severe light pollution, although the use of narrowband filters helped to drastically the extent of its effects.
Imaging Details
Imaging details (Top Image):
Location: Toa Payoh, Singapore
Date(s): September 2019
Telescope: APM LZOS 130 f/6 at f/4.5
Camera: ATIK 16200M
Mount: Losmandy G11/G2
Exposure: 4h 15min in SHO
Imaging details (Bottom Image):
Location: Toa Payoh, Singapore
Date(s): September 2020
Telescope: APM LZOS 130 f/6
Camera: ASI183MM
Mount: Losmandy G11/G2
Exposure: 50 min (HA), SHO colour obtained from above image
Image reduction, integration and processing with Pleiades Astrophoto PixInsight