March 2023 DSO Images

This post is backdated to 3/30/2030 reflecting the month of March period when images were acquired. Setup: Celestron 8 SCT/AVX mount, Starizona Night Owl F/4.0 focal reducer, ZWO ASI294MC Pro cooled camera, Orion Magnificent Mini auto-guider. Processing: Subframes averaging by Autostakkert!3, image processing by Paintshop Pro 2021. 

Messier 46 (3/20/2023)

Comet C/2023E3ZTF (3/20/2023)

NGC2264 (3/20/2023)

Sharpless 252 (3/20/2023)

Messier 93 (3/30/2023)

NGC2360 (3/30/2023)

GraXpert game changing freeware.

A number of weeks ago I stumbled upon a game changing piece of freeware, GraXpert. GraXpert's algorithm analyzes your deep sky image distinguishing stars and nebulosity from back ground sky and generates a background that eliminates gradients and reduces light pollution. A standalone app GraXpert is easy to use while offering settings that allow you to tweak the algorithm for better results. Prior to downloading this awesome piece of free software dealing with gradients, inherent to my  ASI294MC Pro was a bit tedious. With GraXpert you just load the stretched image*, create the grid, calculate the back ground and save the processed image. That's it. You can adjust the sensitivity of the grid creating algorithm to background intensity and you can move, add or delete grid points to distinguish nebulosity from the background. Aside from reducing my workload the colors in my images have improved. Some recent images follow. Thor's Helmet nebula was actually imaged from my 3rd floor balcony in my heavily light polluted south of Boston suburban skies with 120 15s sub exposures. 

*Stretching the histogram in Paintshop Pro seems preferable to the GraXpert stretching routine which seems to throw away black side data. 

Comet C2022E3 ZTF (2/15/2023)

Comet C/2022E3 ZTF  (2/8/2023)

Comet C2022E3 ZTF (1/30/2023)

Comet C/2022E3 ZTF (1/27/2023)

IC443, Sharpless 248, Jellyfish Nebula--Supernova Remnant. 

M42 Orion Nebula

M48 --Open Cluster

Flame Nebula (NGC2024) , NGC2023, Horsehead Nebula(B33)

NGC2264

NGC2353 Open Cluster

NGC2359 (Thor's Helmet Nebula)

M46(NGC2437) Open Cluster + Planetary Nebula NGC2437

NGC2232 Open Cluster

Messier 50 Open Cluster

DSO Images acquired 1/30/2023 -2/28/2023

This is a back dated post to reflect the period during which images were acquired. Setup: Celestron 8/AVX mount, Starizona Night Owl F/4 focal reducer, ZWO ASI294MC Pro camera, Orion Magnificent Mini auto-guider. Averaging of subframes by Autostakkert!3. Image processing with Paintshop Pro 2021.

Comet 2023E3ZTF (1/30/2023)

Comet C/2023E3ZTF (2/8/2023)

Comet C/2023E3ZTF (2/14/2023)

IC443 (2/14/2023)

NGC2359/Thor's Helmet (2/14/2023)

Messier 46 (2/24/2023)

Messier 48 (2/18/2023)

Messier 50 (2/18/2023)

NGC2232 (2/18/2023)

NGC2353 (2/18/2023)

Orion Season Targets + Comet

I've been looking forward to the appearance of comet C2022E3 ZTF's appearance in the northern sky near Ursa Minor. The late January Maryland weather has been iffy at best with mostly cloudy weather forecasts. Fortunately, on 1/27 the skies cleared despite a partly cloudy forecast and around 10:30 PM EST the comet was just high enough and clear of a neighbor's north blocking tree to catch the image below. Some light pollution from a nearby, poorly shielded street lamp managed to invade an otherwise dark sky background. Several to be revisited Orion Season DSOs also follow. 

Comet C/2022E3ZTF (1/27/2023)

NGC1579 Northern Trifid Nebula

NGC2264

M1-Crab Nebula

IC 410 

IC 405 Flaming Star Nebula

Happy 2023 from the Terrace

The condo association gave me an early Christmas gift cutting down the sky obscuring dying tree outside my terrace. Trees across the way still block my light polluted skies. Nonetheless, I now have a descent strip of sky between 20 and 45 degrees altitude to work with during Orion season. I'll still make trips to my favorite darkish site in Harvard, MA but this will cut down on my carbon footprint as well as freezing toes during winter months. An additional benefit is access to WiFi allows me to monitor the scope using Chrome remote desktop. I'm pleasantly surprised with NGC2359 acquired with 15s subs which I first imaged with 60s subs last April from the McCoy's landing darkish site.  I'll definitely revisit NGC2359 between now and April from the terrace. 

The experiment with finder only All Star Polar Alignment has worked better than expected. Typically, I have only needed the two alignment stars plus two calibration stars after rough alignment with Polaris which is not visible from my south facing terrace. Typically less than 2 degrees of azimuth and less than 1 degree of altitude correction have been needed to correct for axis deviation from polar alignment. Thus far the Celestron AVX GoTo puts targets in the NightOwl  field of view (FOV). To center faint targets I just use Precise Goto which puts a bright star in the field which when centered in the FOV and centers the target with an offset.  Below are targets acquired on 12/27/2022 using 60x15s or 120x15s exposures.  Update: M42 reprocessed for reduced contrast and saturation.

M77 Irregular Galaxy

NGC 1788 Reflection Nebula

Left to Right: NGC2024(Flame Nebula), NGC2023, Horsehead Nebula (B33)

NGC2359 (Thor's Helmet) -- To be revisited

Orion Nebula (M42) again 😂

A Few November DSO Captures

Celestron 8 SCT/ AVX  mount, Starizona NightOwl 0.4X Focal Reducer Corrector,

ASI294MC Pro. Typically 120x30s or 60x60s. Update: M2 reprocessed for 

better contrast.

Sharpless 142

Sharpless 170

Sharpless 155

NGC 7023

NGC 281 Pacman Nebula

M2

Alignment and Guiding Experiment

After setting up the telescope I usually do a Celestron AVX all star polar alignment (ASPA) using the visual finder for rough centering then fine centering on the computer screen with the ASI294MC Pro. I thought this might be bit of overkill considering the use of the Orion Magnificent Mini Autoguider. I setup the scope on my 3rd floor patio, as lousy a place for viewing considering no access to Polaris and a tree limited view. The ASPA was performed using the visual finder only starting with  rough north alignment. Jupiter, Saturn were used for alignment and Fomalhaut for calibration star. I usually use two alignment and four calibration stars in the field. Surprisingly only 7' altitude and 7' azimuth corrections were required. Pointing accuracy was less accurate than typical but was good enough to put target on the camera sensor. I had not checked the alignment of the finder with the optical train. This was good enough for M42 but not for NGC2023 so I used precision go to which uses a bright star as a waypoint to the faint target. M42 and NGC2023 with the Flame Nebula and Horsehead Nebula imaged that night appear below. Update: M42 reprocessed for reduced oversaturation.

M42

NGC 2023(center)with Flame Nebula(left) and Horsehead Nebula(right)

Update: A pleasant  start of Orion season surprise. Condo association removed twelve dead trees surrounding my building including the tree right in front of my terrace. Likely the association was prompted by the coming bomb cyclone that will hit Greater Boston with heavy rain and high winds. More sky!! 😀