The Southern Pinwheel Galaxy, M83

After seeing another user on Astrobin (jeryyyyy) post an image of this object even though it was low on his horizon, I decided to try it. I love going after a new target, and I've done a lot of the easy ones by now. Conditions were excellent this night, but this was a very difficult target because it never gets more than 20° above my horizon. I set up my scope way at the back of Mapleton Lateral Observatory (my backyard :) to maximize the clearance above my house, but that created a new problem. Previously, I’ve been able to chain my 10 m and 20 m USB repeater cables with no problem, but VMWare/Windows 7 balks at this and refused to see my USB devices at the end of a 30 m cable on a powered USB hub. I had to cut back down to 20 m, where everything worked fine, but that meant I didn’t have enough cable to get my laptop back inside my house so I had to leave it out in the backyard. It was cold, so I went inside; hence, I didn’t monitor guiding etc. as closely as I usually do. Finding the target was again very simple with the PicGoto Simplificado; the goto (from Gamma Hydrae) was almost dead center. I’m really getting spoiled by this little device, and wonder how I made do without it before.

Date: 28 Apr 2014 Subject: M83, Southern Pinwheel Galaxy
Scope: AT8IN + HPS Coma Corrector
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 no chiller T = 5 °C)
Acquisition: Nebulosity 3.2.0, no dither
Exposure: 19 x 600 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 85%; Develop 81.45%; Color (Scientific) sat. 250%; HDR:Core reveal; Contrast; Sharpen; Deconvolute 2.1; Life:Moderate; Track read noise compensation 5.15%;. CS6 Astronomy Tools increase star color; Deep space noise reduction; Less crunchy more fuzzy; Healing brush; Smudge tool; Astro Frame.

Sharpening Lunar/Planetary Images: Use More Frames

27 Apr 2014.  I recently got a little insight into how the image sharpening in Registax works, and it has implications for how images should be acquired and processed.  I had always assumed the idea was to sort through many planetary/lunar image frames and pick out and use only the sharpest.  That is part of the process, but not all.  Michael Covington, the author of a very nice set of astrophotography web pages and of a book on DSLR astrophotography, described a few days ago on the Deep Sky Stacker Yahoo Group how combining a lot of images that have random noise produces an image that is Gaussian blurred.  Gaussian blurring can be reversed mathematically.  Suddenly I understood why stacked images from Registax always look blurry, usually worse than the individual frames, until sharpening (which reverses that Gaussian blurring) is applied.  So I think this means I should be a bit more liberal about how many frames I stack.  Here’s an example.  In advance, I’ll admit I’m cheating a little bit, because the final sharpened images have been enhanced some in addition to using wavelet sharpening in Registax, but this illustrates the idea. 

This is the stacked image, prior to doing any sharpening.  It definitely looks worse than many of the individual frames.

This is the same data, with 50 frames per alignpoint stacked.

Finally, this is the same data,  but with 500 frames per alignpoint stacked.  I think it is just as sharp as the more selective stack, but is definitely smoother and less noisy.  

NGC 4725, Ring Galaxy in Coma Berenices

After having fun with lunar/planetary imaging for a while, last night I returned to what I like best, deep sky imaging (maybe I like it best because deep sky is what my equipment works best for).  Conditions were reasonably good ahead of a storm (and it is cloudy now as I write this).  Because I had changed everything (principally the telescope, with the Telrad and guider) for imaging the eclipse last week, I had a terrible time getting the Telrad and guide scope lined up tonight; I never did get the guider where it needed to be, but just decided to go ahead.  I could not find the Coma Berenices stars in the Telrad, though I could see them (too dim tonight for my sky conditions and lack of patience with dark adaptation), so I used Cor Caroli instead as my starting point, and that worked fine.  Once again, the PicGoto came through beautifully.  I imaged up past the meridian, then manually did a meridian flip and reacquired the target from Cor Caroli with no problems.  I used 2 markers in Nebulosity to realign after the flip, and that seemed to work very well.  Unfortunately, my guiding after the flip left a lot to be desired.  Still, I think this is better than last year’s image.  Seeing the diffuse outer arms of NGC 4725, I wonder if there has been some tidal interaction with NGC 4712, the galaxy in the right of the image, but I don't know if these two are really close to each other or if this is one of those chance alignment optical illusions.

Date: 23 Apr 2014

Subject: NGC 4725, Ring Galaxy in Coma Berenices

Scope: AT8IN + HPS Coma Corrector

Filter: None

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

Guiding: 9x50 Finder/Guider + DSI Ic + PHD 2.2.1 (Win7 ASCOM VMWare)

Camera: DSI IIc (no chiller T = 6-8 °C)

Acquisition: Nebulosity 3.2.1, no dither

Exposure: 19x480 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%; Rotate 180°; Develop 87.49%; HDR:Optimize; Contrast; Color:Scientific, Sat. 250%; Sharpen; Deconvolute: 2.0 pix; Life:Moderate; Track, RNC 48.28%; Magic:Shrink 1.  CS6+Astronomy Tools deep space noise reduction; less crunchy more fuzzy; increase star color; Gaussian blurred layer mask to enhance outer arms; AstroFrame.

Enhanced View of Total Lunar Eclipse, with Stars

I ran across some beautiful eclipse images this morning that showed the fully eclipsed Moon with stars showing in the background, and realized my data probably had stars too if I stretched them properly.  Sure enough, the stars are there.  So I processed a bit and this is the result.  I’m going to have to create a Photoshop action so I can do a bunch of these and perhaps redo my movie, but for now, here’s a sample.  

Date: 2:05 AM MDT 15 Apr 2014

Subject: Total Lunar Eclipse 

Scope: 9 x 50 Finder/Guider

Filter: None

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

Guiding: none

Camera: Meade DSI Ic

Acquisition: Nebulosity 3.2.1

Exposure: 0.4 s at 100% gain

Stacking: none (single frames)

Processing: demosaic and square in Nebulosity.  CS6 Levels 0.0, 5.04, 58, layer mask; Saturation +51, layer mask; Levels 0, 1.20, 197, layer mask; Astronomy Tools astro frame.

A Closer View of the 14-15 Apr 2014 Lunar Eclipse

17 Apr 2014.  I have finally finished processing my videos of the 14-15 Apr 2014 total lunar eclipse.  They did not come out as well as I had hoped.  I had trouble controlling the exposures of the LPI camera; I just could not get enough from it during the dark parts of the eclipse.  This meant many video frames dropped during the dark parts, and made postprocessing of the images difficult.  It has taken me a while to learn how to process these in Photoshop.  I had intended to try to boost the saturation to make the red color I could see with my eyes show up better in these images, but after lots of messing around I elected to leave it alone (I may want to go back and redo the animated GIF I made from stills using all the things I learned messing with these; they're a lot better aligned than my earlier attempt).  So here it is :

Date: 14-15 Apr 2014 

Subject: Total Lunar Eclipse 

Scope: Orion ST-80

Filter: Baader Fringe Killer

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

Guiding: none

Camera: Meade LPI, 12.5 fps

Acquisition: SharpCap 2.1.915.0

Exposure: 12.5 fps avi, series over about 5 hours, 60 sec of video with 5 minute wait in between, 50 frames total

Stacking: Registax 6, best 30 frames

Processing: Registax 6 wavelets. CS6 combine into animated GIF.  All frames (except the title) are 0.5 s.

I had a lot of trouble trying to control the exposures on the LPI; it does not have a lot of dynamic range.  Also, there are obvious stacking artifacts in many of the subframes.  Finally, the amount of color saturation leaves a lot to be desired.  I probably should have recorded this with greater saturation to begin with, but starting with the full moon there wasn’t a lot of color to calibrate on!  As with the still frames I recorded with my DSI, the eclipse was much more challenging to image than I had anticipated, because the change in light levels was tremendous.

Total Lunar Eclipse, 14-15 Apr 2014, Mapleton, Utah, USA

Once again the PicGoto Group comes through!  I posted a question about using the PicGoto to track at lunar rate, and Ángel Caparros replied with what I should have thought of: lunar rate = sidereal rate x (1 - 1/29), because the moon makes one orbit approximately every 29 days.  So I input that as the RA timer tick and saved it to the PicGoto EEPROM, then used the PicGoto to track the Moon at lunar rate while imaging the lunar eclipse.  Tracking was not perfect; I kept needing to nudge to the northwest, but it was pretty good.

Imaging the eclipse proved to be difficult; I knew there would be issues with the brightness of the Moon changing so much.  I ran two imagers: my Meade DSI Ic on my 9 x 50 guide scope (this is normally my guide camera) taking single frames every 2 minutes, and my Meade LPI with a minus violet (Baader Fringe Killer) filter on the ST-80 scope taking 1 minute of 12.5 fps video separated by 5 minute intervals; with this one the Moon just fits in the field of view.  I have produced an animated GIF from the DSI images, shown below.  Exposures ranged from 0.001 s with the camera gain turned way down for the full Moon, up to 0.4 s at full gain during totality.  Places where the animation seems to pause or even reverse are times I made changes to the exposure.  I intend to produce another animated GIF from the LPI images, but that is going to take a while because I have to put everything through Registax and I do have a day job waiting for me!

Date: 14-15 Apr 2014

Subject: Total Lunar Eclipse 

Scope: 9 x 50 Finder/Guider

Filter: None

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

Guiding: none

Camera: Meade DSI Ic

Acquisition: Nebulosity 3.2.1

Exposure: 0.001 s at about 20% gain up to 0.4 s at 100% gain, series over about 5 hours shot every 2 minutes

Stacking: none (single frames)

Processing: demosaic and square in Nebulosity.  CS6 combine into animated GIF; add 1st frame caption.  All frames except the first are 0.2 s.

Mars at Opposition

Here's my attempt at Mars.  Be gentle; this is my first attempt to image the Red Planet, and at least I got the color approximately right.  The image is an animated GIF.  The whole series covers about 3 hours worth of observation in 22 frames.  I was guiding on a star near Mars throughout this session using the PicGoto Simplificado and my DSI Ic guide camera; the images were 15 fps video at 800x600 resolution taken with a Logitech c270 HD webcam.  The loop begins in darker red (I was using longer exposures) and ends in a paler color as I exposed less.  I'm not sure which I like better.  I had a devil of a time trying to figure out what I was looking at, but thanks to WinJupos I believe the North Polar Cap is about 35° counterclockwise from straight up vertical.  If so, Arcadia and Utopia account for the dark markings just below the polar cap and the dark stuff to the south is Mare Sirenum and Mare Cimmerium.  Amazonis is in the center, which means at the beginning of the loop I’m looking down on Olympus Mons (which of course is not distinguishable in this poor set of images), but it’s still cool to think about. Some clouds are visible in the atmosphere if you look closely and use a little imagination.

Date: 7-8 Apr 2014

Subject: Mars 

Scope: AT8IN + Meade 3x Barlow (f/12, 2400 mm)

Filter: None

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

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

Camera: Logitech c270 HD

Acquisition: SharpCap 2.1.915.0

Exposure: 480 sec, 15 fps AVI, series over about 3 hours

Stacking: PIPP quality selection, Registax 6, 60 best frames

Processing: Registax 6 wavelets (“Full unlinked progressive”), RGB align, fiddle with contrast to optimize image.  CS6 combine into animated GIF.

SharpCap and My Best Jupiter, with Europa as a Bonus

9 Apr 2014.  I don’t normally do much lunar/planetary astrophotography these days because I think deep sky is more interesting (and because my gear is much less well suited to lunar/planetary than it is to deep sky; my focal length is just too short).  However, Mars was just too bright red to pass up.  So I broke out the Logitech c270HD webcam a couple of days ago in an attempt to take advantage of Mars being at opposition.  In addition, I had seen some references to SharpCap (http://www.sharpcap.co.uk/) as a free image capture program for lunar/planetary, so I downloaded it to give it a try.  Mars was the main subject that night, but I got things aligned and tuned up by imaging the Moon and Jupiter while I was waiting for Mars to clear the mountains.  

I love SharpCap and will add that to my toolkit.  It has much better camera control than I'm used to.  I had previously tended to shy away from software that was not Mac-native, but since I got a solid-state drive in my Macbook it has become trivially easy to use VMWare/Windows 7 (the Windows software loads almost instantaneously; with the old hard drive, it seemed to take forever to start up and shut down).  So now I'm not afraid to try out the Windows software, and SharpCap is great.  In addition to better camera control, it also has a focus aid display based on the amount of contrast in your image (which improves as you reach critical focus).  This is a big help for lunar/planetary focusing when the seeing is totally playing havoc with trying to do it visually and I don't want to move off the hard-to-find targets like planets to use a Bhatinov mask on a bright star.  One other feature I really like is SharpCap's ability to take a series of videos of a set duration with an interval in between.  This makes it easy to produce animated GIFs such as the one I took on 7-8 April attempting to show Mars' rotation.

I’m still working on the Moon and Mars images, but here’s one of Jupiter.  I ran the camera at 800 x 600 resolution to improve the frame rate to 15 fps (it only runs at 5 fps at full resolution, which I believe is 1280 x 960).  I didn’t know Europa was in the field of view until I processed the image stack and tried enhancing it.  I also recently learned about RGB alignment in Registax, and that helped with Jupiter but not with Europa (I didn’t know it was there at that point in the processing).  Overall, I think this is my best Jupiter so far; not terrible given the focal length at which I was working.  

Date: 7 Apr 2014, 9:29 PM MDT

Subject: Jupiter with Great Red Spot and Europa

Scope: AT8IN, 3x Barlow stacked (f/12, 2400 mm)

Mount: CG-5

Guiding: none

Camera: Logitech c270 HD at 800 x 600

Acquisition: Sharp Cap 2.1.915.0

Exposure: 120 sec, 15 fps AVI

Stacking: Registax 6, automatic alignpoint selection, best 50 frames/alignpoint

Processing: Registax 6 wavelets, RGB align. CS6 layer mask to make Europa visible without blowing out Jupiter, saturation enhance.



And as a postscript, I just have to mention that yesterday I got word that my November 2013 U.S. National Science Foundation proposal, dealing with a new method of measuring molecular sizes (technically, collision cross sections), has been recommended for funding.  I'm ecstatic about that. This was an unexpected bit of wonderful news.  I knew the proposal contained some really good ideas, but funding for basic science in the U.S. recently has been extremely hard to get (most of us describe the current situation as "toxic"), so I feel very fortunate and look forward to doing more good science.