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Gabriela Mistral Nebula and the Gem Cluster

Been sitting on this dataset for a while, finally got around to finishing and publishing it! I had a lot of trouble with my system as most of this data was taken whilst I was sleeping and I could not baby it. I believe I ended up chucking over 30hrs of bad data. (Had many clear nights to 'spare'). The resulting dataset is still far from perfect but oh well. This is a ~27.44 hr Ha LRGB image of the Gabriela Mistral Nebula and Gem Cluster, right next to the carina nebula.

Acquisition Details:

Scope: GSO 8" F/4, flocked, 2" moonlite, DIY AutoFocuser, DIY Secondary Dew Heater Coma Corrector: SkyWatcher Aplanatic/Quattro Camera: ZWO ASI 1600MMC PRO (Image scale ~1"/pixel) Mount: EQ6-R Guide Scope: ZWO 60mm Guide Cam: QHY5LIIC All ZWO LRGBSHO filtersAcquired on many many nights :( Subs & Integration times: Ha: 177 x 300s (14.75 hrs) L: 137 x 120s ( 4.56 hrs) R: 69x 120s (2.3 hrs) G: 97 x 120s (3.23 hrs) B: 78 x 120s (2.6 hrs) Grand Total: 27.44 hours All at unity gain, 21 offset, -15 degrees celsius Acquired with the NINA imaging suite. Guided with PHD2. Mount interface: EQMOD

Processing Details:

All subs flat and dark calibrated All subs weighted with SFS. Star aligned, Integration Drizzle Integration 1x scale with dropshrink of around 0.7, variableK=1.5. All stacks were cropped, and ABE degree 0 subtracted. HA: DECON, TGV NR, Then combined with L using a modified version of the LVA guide on enhancing L with Ha (the second step of pixel math gave a bad result so I modified it) More TGV NR, then HT stretch, some curves and LHE was then applied with various range masks. The RGB was linear fitted together, channel combined, HT stretch. SCNR on green, various curves on a*, b* and saturation then finished with a contrast curve. Then it was LRGB combined with modified transfer functions parameters to preserve the colour. Careful star reduction with a contour mask was applied (took a lot of trial and error), Various LHE and curves applied, some color masking to target the nebulosity. Curve on K to darken the bg a bit. AdvSharpening was then applied, pixel mathed 0.5*orig + 0.5*sharpened.
Date Created: 2020-02-05
Date Posted: 2020-03-09