Hemisphere:  Northern  ·  Contains:  IC 1805  ·  IC1805  ·  Sh2-190
Getting plate-solving status, please wait...
Open Cluster Melotte 15 in Cassiopeia - sh2-190 / IC1805 - SHO, 


Powered byPixInsight

Open Cluster Melotte 15 in Cassiopeia - sh2-190 / IC1805 - SHO

Acquisition type: Electronically-Assisted Astronomy (EAA, e.g. based on a live video feed)

Imaging telescopes or lenses: TS Optics APO130f6

Imaging cameras: ZWO ASI1600MM-Cool

Mounts: Ioptron CEM 120 EC2

Guiding telescopes or lenses: TS Optics APO130f6

Guiding cameras: Starlight Express Lodestar X2 Autoguider

Focal reducers: TS-Optics TSFlat 2

Software: Sequence Generator Pro  ·  PixInsight  ·  PHD Guiding 2.5.0

Filters: ZWO new B  ·  ZWO new G  ·  ZWO new R  ·  AstroDon 5nm Ha filter  ·  AstroDon 5nm SII filter  ·  AstroDon 5nm OIII filter

Accessory: ZWO EFW 31mm 8 positions  ·  QHYCCD PoleMaster  ·  Innovations Foresight ONAG  ·  USB_Focus V3 Usb Focus  ·  USB Stepper Motor Heavy Load

Dates:Sept. 14, 2019

AstroDon 5nm Ha filter: 45x600" (gain: 139.00) bin 1x1
AstroDon 5nm OIII filter: 43x600" (gain: 139.00) bin 1x1
AstroDon 5nm SII filter: 39x600" (gain: 139.00) bin 1x1
ZWO new B: 5x120" (gain: 139.00) bin 1x1
ZWO new G: 5x120" (gain: 139.00) bin 1x1
ZWO new R: 5x120" (gain: 139.00) bin 1x1

Integration: 21.7 hours

Darks: ~20

Flats: ~5

Flat darks: ~25

Avg. Moon age: 15.05 days

Avg. Moon phase: 99.91%

Mean SQM: 3.00

Mean FWHM: 19.50

Astrometry.net job: 3003196

RA center: 2h 33' 8"

DEC center: +61° 26' 54"

Pixel scale: 0.908 arcsec/pixel

Orientation: 0.091 degrees

Field radius: 0.733 degrees

Resolution: 4634x3502

Locations: Duc, Prayssas, Lot et Garonne, France

Data source: Backyard


This image results from exposures spanning over 8 nights : 14, 15, 16, 17, 188, 19, 20 & 22 of september. As the nights were getting longer in september, I let the scope point to this nice area of the sky during the second half of the night.

Despite the nearly full moon shinning, the NB filters did a nice job. However, flats correction was needed to calibrate SHO frames! This is not necessary (with my equipment) on moonless night.

The cooling of the sensor varied at -12C, -15C & -21C, depending on the outside temperature.

The RGB exposures were only used to give a natural color to the stars.

The processing was performed in PI as follows :

For each S, H, O, R, G, B channels :
- Images Calibration (Dark Substraction)
- Cosmetic Correction
- Image Registration
- Image Integration
- Mure Denoise (for SHO only)
Then :
- Create a super Lum image from S, H & O channels (weights estimated using PI integration on S H O images before noise reduction : 1.0 for Ha, 0.1 for O3 & S2.
- Deconvolution of super Lum masked with 2.3 pixel psf
- Create SHO image using LRGB
- Color balance on nebula and color saturation using mask to protect dark area.
- Create RGB image and color balance and color sat (to be used to color stars in SHO)
- SCNR (G neutral and min)
- Background extraction
- Going NL using HT for SHO & RGB images
- Color Saturation masked (and desaturate bkg)
- Color Saturation masked using stars to desaturate stars
- Apply "a" & "b" color channels of the RGB image under star mask
(this is to apply natural color to the stars)
- Local Histogram Equalisation
- TGV denoise (no mask)

Final image adjustments performed in Iphoto on Imac :
- levels adjustments
- adjust color looking using "selective color"
- boost sharpness
- deflip
- crop



License: None (All rights reserved)

Sky plot

Sky plot


Open Cluster Melotte 15 in Cassiopeia - sh2-190 / IC1805 - SHO, 



In these public groups

Sharpless2 Objects