The Dumbbell Nebula (also known as Apple Core Nebula, Messier 27, M 27, or NGC 6853) is a planetary nebula in the constellation Vulpecula, at a distance of about 1,360 light-years. he Dumbbell Nebula appears to be shaped like an prolate spheroid and is viewed from our perspective along the plane of its equator. The central star, a white dwarf, is estimated to have a radius of 0.13 light seconds which gives it a size larger than most other known white dwarfs. Most images of this nebula that we can find on the web that made by amature Astro imagers will show the inner core of the nebula since most imagers uses Luminance and color filters with mono cameras, or use color cameras, by adding a narrowband filters Hydrogen-alpha (H-a) and Oxygen (OIII) it will revile the outer layers (shell) of the nebula like shown in this image.
This image is a version made with LRGB, H-a & OIII filters.
Image taken from the Negev desert Israel on Jul 7, 2018 & Aug 8, 2018, two night sessions.
LUM: 17X600sec @ -10*c` bin 1x1.
Red: 6X600sec @ -10*c` bin 2x2.
Green: 6X600sec @ -10*c` bin 2x2.
Blue: 6X600sec @ -10*c` bin 2x2.
H-a: 14X1200sec @ -10*c` bin 1x1.
OIII: 7X1200sec @ -10*c` bin 2x2.
Total integration time: 13 hours.
Calibration frames: 20 Dark, 200 Bias, 30 Flat @ bin 1x1.
20 Dark, 200 Bias, 30 Flat @ bin 2x2.
This image has made with a scope focal length of 1200 mm.
CCD camera sensor resolution 2700x2200 pixels.
Mount- Losmandy G11 G2 modified
Scope- William Optics 152mm f/8 LZOS OK-4 optics
Camera- Starlight Xpress Trius SX694 mono & SX Filter Wheel & Astrodon 36mm unmounted E series Gen2 LRGB,Ha,OIII
Guider- SX Lodestar & SX OAG
Flattener- TSFlat2.5, 2.5".
Camera & mount control- SGP via Ascom
Sky chart- Stellarium
Mount main control- Gemini.net via Ascom
Registration, Calibration & stacking images- Maxim DL5
Processing- PS CS6