Visiting the Pillars of Creation

This is another “looking at progress” entry.  I guess I do that a lot, but that is much of the fun of astrophotography for me—seeing improvement.  It was a great thrill back when I first tried to image the Eagle Nebula and realized that I could see the “Pillars of Creation,” made famous in Hubble Space Telescope images, in my own humble efforts.  I had not “visited” the Eagle last summer (and I do think of imaging these objects in terms of visiting them; it's the closest I'm ever going to get!) because we didn’t get very many good nights and the few we did get seemed to be marred by smoke from wildfires (plus last summer I was doing a lot of playing with wide-field images taken using my 9x50 guide scope).  Anyway, last night it looked like conditions were going to be excellent and I reasoned the Eagle was about at the right place in the sky that I could image it all night (and I needed my sleep after staying up most of the night before, so the plan was to start the session and just let it run).  

M16 has several common names: Eagle Nebula, Star Queen Nebula, and Pillars of Creation (as noted above).  I like Eagle Nebula, both because the dark structure at the center reminds me of an eagle and because the overall nebula (which you can't see in this image because it is framed too tightly for it) resembles an Eagle with wings spread.  That two-levels-of-meaning thing appeals to me.

I had trouble getting the Cartes du Ciel/PicGoto combination to work correctly.  I tried to start by synchronizing on nu Oph and each time after doing the goto for M16 the chart would jump to some position to the west of where it really was and not find the target.  So I finally switched to alpha Sct (which was just visible), synched there, and did the goto; no problem that time.  Despite looking promising in the forecast, conditions were not great: gusty wind, poor seeing, and some smoke in the air.  So guiding performance was terrible, worse in RA than in DEC.  Nevertheless, after throwing out the worst subframes and some processing, this is the result:

Date: 28 Jun 2014

Subject: M16, Eagle or Star Queen Nebula

Scope: AT8IN

Filter: none

Mount: CG-5 (Synta motors, PicGoto Simplificado)

Guiding: 9x50 Finder/Guider + DSI Ic + PHD 2.2.2 (Win 7 ASCOM)

Camera: DSI IIc chiller at 2.50 A, ~10 °C

Acquisition: Nebulosity 3.2.0, no dither

Exposure: 39x300 s

Stacking: Neb 3, bad pixel map, bias included, normalize first, trans+rot align, 1.5 SD stack.

Processing: StarTools 1.3.5.279 Crop; Wipe:Color & brightness 77%; Develop 82.80%; HDR:Optimize; Color:Scientific, 200%; Life:Moderate; Deconvolute auto mask 2.9 pix; HDR:Equalize; Track RNC 1.72%; Magic:Shrink 1 pix; Color:Scientific, 150%.  CS6 Astronomy Tools Increase star color; Less crunchy more fuzzy (twice); Layer mask to retain detail in the nebula; Astro Frame.

Compare with the image from 2 years ago, here.  The new image is much sharper and I like the colors better.  

Date: 25 Jul 2012

Subject: M16, Eagle Nebula

Scope: AT8IN (no focal reduction!) 

Filter: none

Mount: CG-5 (Synta motors)

Guiding: Orion ST80 + 0.5x Antares telereducer + DSI Ic + PHD

Camera: DSI IIc 

Acquisition: Nebulosity 3.0.9

Exposure: 36 x 300 s 

Stacking: Neb 3, bias included, normalize first, trans+rot align, 1.5 SD stack

Processing: auto color balance, digital development with sharpening, Keller stretch, power stretch, star edge sharpen. In one layer, unsharp mask. In separate layer, GREYCStoration. To the denoised layer in CS5, Astronomy Tools deep space & space noise reduction. Combine with Gaussian blurred layer mask. Saturation boost and levels.

Reprocessed with StarTools.  Tightened the fat stars, healed the star shapes, and finished with Life:Moderate with a 90% saturation boost.