A comparison with Hubble helps to distinguish the various features I have captured in this
tiny object - the set of inner bright hourglass rings together are less than 10 arc sec across.

At a distance of about 10,000 light years, this tiny planetary nebula Hen2-104 in Centaurus
has an apparent size of just 80" X 40" making its actual size about 6.5 light years in diameter.
Hen2-104 is a Symbiotic star system composed of a Mira type giant and a hot white
dwarf star in close proximity. This nebula is known as the Southern Crab Nebula due to its
shape resembling the claws and legs of a crab.

An excellent paper on Hen 2-104 can be found here: http://arxiv.org/pdf/0803.0448.pdf

Orion Optics UK AG12 F3.8
Starlightxpress SXVF-H694, SX USB CFW, SX OAG unit + Atlas Focuser
SIIHaOIIIRGB = 432 360 375 45 45 45 = 21.7hrs total exposure (bin 1X1)
Using Astronomik 6nm Narrowband filters and RGB Deep Sky filters
-20C chip temp, flats used but no dark frames were used.
Focal length 1120mm
Image scale 0.84"/pix
Guide Camera: Starlightxpress Lodestar

Comments
Taken over 3 nights - 15, 27 and 30 April 2017, some moon, average to good seeing.

Equipment setup:

http://www.pbase.com/strongmanmike2002/sxvrh694_gear

Some links to equipment used to take this image:

Orion Optics UK

http://www.orionoptics.co.uk/

StarlightXpress CCD Cameras and imaging equipment

http://www.sxccd.com/products

Finger Lakes Instrumentation CCD cameras:

http://www.flicamera.com/

Astro Shop (Aus)

http://www.astroshop.com.au/

Astro-Elecronic FS2 scope GOTO controller:

http://www.astro-electronic.de/

Gerd Neumann and Astronomik filters:

http://www.astronomik.com/en/home

http://www.gerdneumann.net/

MSB Software & Astroart 6

http://www.msb-astroart.com/

Catseye Collimation

http://www.catseyecollimation.com/

STAR Atlas:PRO planetarium software:

http://www.staratlaspro.com/