Link to inverted images
We 2-262 (PK 116+00.1, PNG 116.1+00.4) was discovered by R. Weinberger during a survey for strongly reddened galaxies on the Palomar Observatory Sky Survey plates, and was included by Weinberger in his 1977 paper listing 335 objects designated as possible, probable or true planetary nebulae since the closing of the 1967 Perek-Kohoutek PN catalog. While Weinberger at the time regarded it as one of the most promising PN candidates, by 2008 Frew had concluded that it was merely an HII region. In my imaging, We 2-262 didn’t show at all in 14 hours of OIII, giving further reason to doubt that it’s a PN. The HASH PN database at hashpn.space lists the object but is silent on its status, but SIMBAD still lists it as a PN candidate. Although it’s occasionally imaged in widefield views of the large supernova remnant CTB1 (Abell 85), I found no other discussion of its status, except for one paper which calculated its distance as 5300 light years.
The nebulosity in this image is from the colorized Ha data. The stars are RGB.
Exposure: Total exposure time about 30 hours, 42 x 20 mins Ha, 42 x 20 mins OIII, 40:41:42 x 2 mins R:G:B. All bin 1x1. Captured July to Oct 2022.
Light pollution: SQM ~18.38 (Bortle 7-8, NELM at zenith about 4.5, Red/white zone border.)
Seeing: FWHM of integrated narrowband images around 2.5 arcsecs
Image scale at capture: 0.6 arcsecs/pixel = f/5.7
Scale of presentation: 1.2 arcsecs/pixel (50% of full scale)
Equipment:
Scope: C11 (standard, not Edge) with Celestron 0.63 reducer
Mount: Paramount MX+, connected via ASCOM Telescope Driver 6.1 for TheSkyX, with MKS 5000 driver 6.0.0.0
Camera: SXVR-H694, connected via SX ASCOM driver 6.2.1.17140 (SX 1.2.2 also installed)
Filter wheel: Atik EFW2 with 7x1.25 carousel and Artemis 2.4.3.0 driver
Filters: Astrodon Type IIi LRGB
Rotator: Optec Pyxis 2", connected via Andy Galasso's 0.4 driver (Optec Pyxis Rotator AG)
Focuser: Rigel Systems GCUSB nStep motor with driver version 6.0.7 on stock Celestron focuser
OAG: Orion Thin OAG
Guide cam: Lodestar (first generation). 4 second exposures
Automation SW: Sequence Generator Pro 3.1.0.457
Guide SW: PHD 2.6.7, connected to guide cam via native SXV driver
ASCOM: ASCOM 6.3.0.2831
Platesolving: PlateSolve 2, failover to local Astrometry.net 0.19 server
Collimation: Metaguide 3, using ASI120MM connected via ZWO Direct Show driver 3.0.0.2
Processing Software: Pixinisight, Affinity Photo, Photoshop CS2
Processing Workflow by Workspace in PixInsight 1.8.9:
1. Calibration
Calibration with WeightedBatchPreProcessing with flats and bias, using Cosmetic Correction with a master dark
Blink to preview and reject a few frames
Weighting and registration with WBPP
2. Stack and Mure Denoise
Image Integration on each channel
Mure Denoise on each channel
RGB Combination for RGB frames
Dynamic Crop on both narrowand and RGB
Dynamic Background Extraction
3. Narrowband Linear Processing
(No deconvolution on this data)
4. Narrowband Stretching
Histo Trans x 2
Curves Trans
TGV Denoise
Aggressive Multiscale Median Transform denoise (with an inverted luminance mask) to remove background lumpiness
5. RGB Linear Processing
Platesolve with ImageSolver
Spectrophotometric Color Calibration, using Average Spiral Galaxy white reference
6. RGB Stretching
Histo Trans x 2
Boost color saturation with Curves
Histo Trans
Curves Trans
7. Colorization
Remove stars from Ha with Starnet 2
Convert Ha to RGB Color
Curves Trans on Ha, anchoring the background in all three color channels, then pulling down green and blue and pulling up red to get the proper color in the nebula
Pretty much blast the background with Convolution and heavy Multiscale Median Transform to even out the lumpiness
PixelMath to add RGB stars to colorized Ha using the formula “((1-$T)*(stars))+$T”
8. Final
Final Histogram Transformation
ICC Profile Transform to sRGB
Resample at 50% scale
Save as JPG
