40h NGC7000 mini mosaic!

[jmtanous]

Hi,
 
Last week we had the darkest and cleanest nights in years. I was impressed by the amount of data I was able to gather on 2 particular nights, on the other side the seeing was not great.
 
I continued with my project of imaging the Cygnus Wall and finally I had all the data needed to put together my mosaic. Processing was challenging cause the Cygnus Wall has some very bright regions so stretching was tricky.
 
The image details are:
 
-- Camera: Atik 460EX
-- Mount: Takahashi EM200
-- OTA TPO (GSO) 10 inch F/4 with Televue Parracor effective speed f/4.6
-- Guiding PHD2 SX OAG with Lodestar
-- Filters Narrowband Astrodon 1.25" @ 5nm
-- Capture and Automation with Sequence Generator Pro
-- 20 x 20m x filter x tile. Total Exposure time 40h
-- Processed with Pixinsight

I hope you like the image, this Chinese scope is far from a turn key system but the optics are good.
 
CS,
 
Jose

[Geoff]

Spectacular Jose.   Has a real 3D look about it.  Did you use the J-P Metsavainio technique outlined here http://www.radice.biz/articoli/translations/75-narrowband-color-composition-eng ?  The stars look very natural (aside from the fact that they have no colour).
Geoff

[jmtanous]

Hi Geoff,

Thanks for commenting about my image.

I knew about JPM method but I didn't use it. I used a very simple way to mix narrowband images.

-- Stretch each channel individually to a similar level.
-- Mix the channels using Pixelmath, similar weights per channel
-- Remove the green cast using the histogram tool
-- Remove the magenta using http://pixinsight.com/forum/index.php?topic=7377.0
-- Historgram, sharpening using ATwavelests, curves to make the image pretty
-- Saturate at will
-- The colors are nice but the stars are crap. No worry, extract L channel and using the an star mask completely desaturate the stars. Mix back the L channel with the LRGB combination tool checking the color noise reduction option, this will remove color holes and imperfections around the stars.

The TV Paracorr is the best corrector out there, it tolarates tilt quite nice and it doesnt show any trace of spherical aberration. It is expensive (not close to the ASA's tho) and it increments the FL by 1.15

CS,

Jose