Thursday, July 12, 2018

SH2-101 Tulip Nebula Finished

I finished this image of the Tulip Nebula (SH2-101) by adding the RGB (color) over the past few nights. The nebula is a HII region about 6,000 light years away in Cygnus.  It looks really cool that it is done but the individual frames looked like nothing.  The Ha data really made the tulip and the rest of the nebulosity stand out.  Although I took the color frames without any filter, I would recommend using a UHF if an Ha filter was not available.   For anyone who doubts the usefulness of adding Ha-images to color images I did a comparison of what I did to combine the images.  Basically I followed the Trevor Jones (Astrobackyard.com) directions for adding Ha-data to color data.

1) The Ha image (Ha) was created first over three nights when the moon was full or near full. I followed my normal procedures but stacked the frames using super pixel mode.

2) The color image (RGB) was done normally as well however at the recommendation of Shannon Calvert who was also imaging at the site, I switched to 800 ISO in order to lesson the noise which my old workhorse T3i seems to produce.

3) The Ha-image (HaR) was added to the the red channel of the color image to provide an initial boost.

4) The Final Image (HaRRGB) was produced when the Ha-image was added to the Enhanced image using the luminosity combining method. 

Addendum:
So I decided to redu my last object before changing over to PI.  I never was truly happy  background so though I would give PI a try.  I was unable to do my new normal HaRRGB method because there was a problem with the Ha stacked file, it had this horizontal -vertical pattern to it so I had to get rid of most of it with curve stretching.  It was not in the one I did four months ago with DSS so I think the problem is one set of flats is corrupt.  This also prevented the additional nebulosity from being visible.  If I get some more free time I will play with this again.  I think the star field looks really cool so I only did a 33% star reduction with morphological trans.  I am in the middle of trying to finish Andromeda but I have been very sick the last week and the weather has not been ideal either.  Also, I switched the orientation and did not us PS at all. 

Quick Pic 

Ha

RGB (Color)

Enhanced HaR

HaRRGB

HaRGB

SH2-101 - Tulip Nebula
Location: Happy Frog Observatory, Monroe, CT; Paine Open Space, Easton, CT
Date: 06-25-18, 6-28-18, 6-30-18, 7-8-18, 7-9-18
Camera: Canon EOS Rebel T3i(a), AstroPhotography Tool APT, Backyard EOS
Telescope: Orion ED80 80mm f/7.5 Apochromatic Refractor Telescope
Barlow: None
Focal Length: 600mm
f/7.5
Focal Reducer: Orion 0.8x Focal Reducer for Refractor Telescopes
Mount: Orion Sirius EQ (HEQ5)
Filter: Astrodon UV/IR, Astronomik 12nm Ha
Autoguiding: QHY-5L-II-M attached to an Agena 50mm Guide Scope with Helical Focuser
Exposure: 48 x 180s, 20 x 180s, 36 x 180s, 50 x 120s, 46 x 150s
ISO: 1600 (Ha), 800 (RGB)
Temp: 18 C, 20 C, 20 C, 18 C, 17 C
Post Processing: Deep Sky Stacker, Photoshop, Gradient Exterminator, Astronomy Tools, StarTools, Lightroom
https://kurtzeppetello.smugmug.com/

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