The M16 image by CielAustral is captured with G4-16000 camera on 0.5m
CDK telescope in Chile. It naturally lacks the details provided by
Hubble Space Telescope in the nebula center (but if you download the
image in full resolution, the difference is not that big if you
consider HST is a multi-billion-dollar space telescope with 2.4m
mirror), but is offers much wider field of view and overall impression
excellent.

As usual, CielAustral group (Jean Claude Canonne, Nicolas Outters,
Philippe Bernhard, Didier Chaplain and Laurent Bourgon) acquired
images through both narrow-band Hα, OIII and
SII filters to extract maximum details from interstellar nebulosity
and in red, green and blue filters to show the nebula in natural
colors, similar to human’s eye perception. Total exposure time of
narrow-band image exceeds 44 hours, RGB image needed only 5 hours
because red, green and blue filters pass much wider portion of the
incoming light compared to narrow-band filters and thus achieves good
signal-to-noise ratio in much shorter time.
Still, the real-color image above inherits the sharpness and
details in nebulosity from the narrow-band image, as it used also
Hα data for red color and OIII data for green
and blue colors.
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