Scope:
AT60EDP at f/5;
Location: DAA Observatory, Shelter
Valley, CA;
Dates:
9 September, 16, 17, 20, 23, 24, October, 2025;
Camera:
ASI2600MM (Astronomik type 2c LRGB, 6 nm Ha and OIII filters);
Exposure:
40.26 hrs
Lum -
135 x 3.5 min (gain-101 1x1)
RGB -
48 x 2 min (gain-101 1x1) each RGB exposures.,
Ha - 171
x 5 min (gain-180 1x1)
OIII -
160 x 5 min (gain-180 1x1)
Processing:
Data
Collection - N.I.N.A. Sequencer (as FITs). Sub-frame calibration -
Pixinsight (WBPP).
Sub-frame registration and integration (Average combine
- Linear clipping), Lum, Ha, OIII (2x drizzle) - PixInsight (WBPP).
Noise reduction - NoiseXTerminator - PixInsight.
Non-linear
stretching, normalization and gradient removal - PixInsight.
Photometric
RGB calibration (SPCC) - PixInsight.
Deconvolution
of Lum, Ha, OIII, stacks and RGB combine - BlurXTerminator.
Generation
of starless nebulosity Lum, Ha, OIII , and RGB images for later processing
- StarXTerminator.
Curves,
Levels, RGB combine - PixInsight. RGB Stars and starless combine -
PixInsight.
Final
finishing - Affinity Photo.
Annotation
- PixInsight, Aladin (Simbad ), and Affinity Photo.
This
image is a modified HOO Narrow Band and screened LRGB starless
construction - with RGB stars added. Image processed at 12496 x 8352 resolution.
Final
Image size is approximately 4326 x 6502.
Description:
North is left in this image. This
is the Planetary Nebula PN G158.5+00.7 (Sh2-216) - a very close neighbor
to the our solar system. It has a distance of about 426 light years. It is about
12 light years in diameter.
The PN's Central
Star is WD 0439+466 (LS V +46 21). But it is not in the geometric center of the
PN (in our line of sight from the Sol system). This is due to it's interaction
with the galactic ISM and magnetic field as the PN system is in motion relative
to this ISM. It also causes a bright compression in the northeast (lower left of
the PN in this image).
Also in this image
are Barnard 15 and 25, LBN 742, 744, 754, and 755, LDN 1444, 1445, 1465, Open
Cluster NGC 1605, and Sh2-219.
