Monday, November 6, 2017

June Observing Report

June 16, 2017
The clearest night in weeks but still hazy and the mosquitoes are thick. At 2107 the temp is 82 F with 75% humidity with no breeze. Two changes since last session; a new HP Omen laptop and an auxiliary dew heater for the ASI071MC-COOL from ZWO.

In trials the new laptop collected > 70 frames without a drop so I'm hoping to avoid loosing frames as I have in past sessions. Also as the new laptop has HDMI output, I'm using a 4' VIZIO premium high speed HDMI cable to drive the HP w2338h monitor. I've ported most of my software over to the new laptop including, SharpCap, PhD2, AstroToaster, Deep Sky Planner, and Open Office with my observing diary. So off I go.

H 95-1 NGC 4214
The galaxy is elliptical with multiple bright regions or stars between it and earth. The galaxy is oriented NNW to SSE. In the NNW end there is a bright region (possibly 3 stars) that are to the W of the main galaxy axis. There are within the galaxy 4 bright regions along the axis. The galactic halo is roughly 6' x 4'. To the NNW about 9' and just to the W of the galactic axis lies a bright double star. To the SE there is a short line of 3 stars about 5' from the galaxy. The furthermost star in this line appears to be a double.

8 x 4 min., gain 400, chip temperature = -10C, dark frame corrected in AstroToaster

There was a dark triangular patch across the upper left of the image that faded with time. By image 6 it was greatly diminished and by frame 9 it was nearly gone. Not sure what this is as there were no clouds I could see. Unlike anything I've experienced before. That the object is in the west also hurts my contrast.

To compound the issues with this image, I neglected to engage the autoguider and that has lead to significant image shift in images 10 up. What frames I have will suffice for a good observation of the object but I won't win any photo contests with this one. On a positive note I had no dewing of the camera with the new auxiliary dew heater on.

While capturing the images for this object I noted that the camera counts only 1 sec beyond the exposure setting and then begins the next capture. With the old laptop the camera would go 10-20 seconds beyond the exposure setting. Clearly the new laptop's speed is paying off.

At 2301 it is 77 F with 87% humidity. Skymeter reads 18.97, better than I expected based on the cloudiness of late afternoon.

June 23, 2017
My Gemini software & firmware haven't been updated since I bought the mount in 2014 and there have been several updates published. The first step was to establish connectivity between my laptop and the Gemini system.  I set up the HP Omen laptop to talk to the Gemini system via ethernet cable through a Pluggable USB 2.0 Ethernet Adapter. No cross-over adapter was used. I had to assign a static IP address to the Ethernet adapter using the excellent instuctions on Tom Hilton's webpage; http://gemini-2.com/crossovernetwork.php#Win7 . Following the instructions for the “direct method” I was able to log onto the Gemini web interface. The ethernet connection shows up in the Network Sharing Center as “Ethernet 3”. To access the web interface, I used Chrome and in the address bar entered the address http://192.168.0.111. The web interface operates the mount and accesses the functions in the hand controller. There is no indication given on the hand controller that a computer is accessing the Gemini system.


I ran the GFU per the instructions at http://www.gemini-2.com/gfu.php . The download failed at 20% and so I hit start again and the download seemingly froze at 71% for over 10 min. After some experimentation I determined that my internet speed was extremely slow. After relocating my WiFi bridge to get a stronger signal, I retried the GFU and it worked! As the instructions advised, the GFU did error out after the SRAM Reset. I cycled the power on the Gemini and it started flashing the hand controller. It worked !! Now my Gemini's firmware is updated - WooHoo !!



I closed and restarted the GFU to update the catalogs . The download does take a long time (> 15 min) for the Gemini to upload the catalogs to the hand controller. Now my catalogs are up to date also. It took a long time to resolve the internet connectivity issues, but I achieved the desired result. Now I just need a clear night so I can observe.

June 30, 2017
Came out a little after 9 pm on a warm, muggy night. The sky is reasonably clear for the first time in weeks. Will be my first time using the newly upgraded Gemini system. Installed the ASI071MC-COOL at prime focus with the Lumicon Deep Sky filter.

Slowly cooled down the camera to -10C but I got some distortions on the right side of the image and a small black crystalline shape near bottom center. There also appeared to be some darkening in the center of the FOV. I raised the temp to 10 C and it looks a bit better. The dewing/freezing issues with this camera are very frustrating.

H 584-2, NGC 6235
A smallish (~ 5 ') globular cluster (GC), roughly circular in shape, in a dense star field. The core is very compact with only a few discrete stars discernible. On the E side there is a long line of stars running from the SW to the NE. On the W side there is a semi-circle of 5 stars, one of which appears to be a double.
stack of 4 x 180 seconds, gain = 400, chip temperature = - 10 C, no dark frame subtraction

H 11-6, NGC 6284
A compact GC in a dense star field. The GC is roughly circular brighter stars in the S half. Stars in the center are not discrete but merged. Apparent size is ~ 4 '.
stack of 4 x 180 seconds, gain = 400, chip temperature = 10 C, no dark frame subtraction

H 48-1, NGC 6356
A circular GC with a bright core that is unfortunately blown out in my 120 second images. The GC sits in a dense star field of fairly uniform distribution. There are 2 larger stars in the FOV to the ENE of the GC about 10 & 20 ' distant.
Stack of 4 x 120 seconds, gain = 400, chip temperature = 10 C, no dark frame subtraction

At 2325 it is 78 F and 95% humidity. Sky meter reading is 18.38. Not a bad night given the heat, humidity, half moon in the W, and occasional clouds. Clouds became more prevalent after 2300 and I shut down at 2350.

Thursday, November 2, 2017

May 2017 Observing Report

May 1, 2017
Came out around 2130 on a clear warm night. Setup the scope again at prime focus using 4” of focuser rings and both the Lumicon Deep Sky and the Badder UV/IR filters. Used the SharpCap Bhatinov mask focusing aid to bring in the focus @ 35 mm and then synced the model on Arcturus. I cleaned both filters so hopefully I got rid of that dark circle in my images last night. Earlier today I down loaded the newest Sharpcap 3.0.3855.0 . Will see how it works tonight. At first look, it is virtually identical other than a few new options like flat creation and subtraction. Not thrilled that in order to do dark field subtraction I have to buy the license. At 10 British pounds / year it isn't that much money, but a trial period would have been nice.

H28.1-4 NGC 4038 & 4039 – Antennae galaxy (ARP 244) 
A wonderful enigmatic object.  Two interacting galaxies (NGC 4038 & 4039) in what looks like a larva with a circular head.  There are 4 bright regions in the tail section and 6 or more in the circular head.   There is only a hint of one of the wispy curving extensions that are shown in more detailed photos.  The FOV contains 2 bright stars and > 2 dozen fainter ones.  
Took a set of 4 min images. The light curve maxima is still only around 15%, so not a lot of signal even at 240 seconds.
Stack of 8 x 240 seconds, AGC = 400, camera at -10 C, dark frame subtracted

crop of above image


At 0049 it is 57 F with 98% humidity. Sky meter reading is 19.11.

H 587-2, NGC 6426
A smallish (~ 2 ') GC  in the constellation Ophiuchus approximately 67,500 light years from earth.  The GC is roughly circular shape.  There are only around 8 discernible bright stars in the GC core and many fainter ones.  The FOV is well populated.

stack of 5 x 180 seconds, gain = 400, chip temp = -10, dark frame corrected


crop of above image


This target would have benefited from longer exposures and more frames but even with targets that are 37 deg high and 110 in azimuth I am experiencing guiding performance in both axis!

I'm now getting a dark circle in the middle of the image that is obscuring the target !! ARGH !!! Turned cooler set point to 0 and then 10 to thaw it out. This is really frustrating. I know it is damp out but with the descant tabs the chip should stay dry enough to not fog over. I have the dew shield on the scope so the scope should not be fogging over.

H 72-8, NGC 6633
A nice bright OC in the constellation Ophiuchus consisting of about a dozen brighter stars and many fainter ones.  The central area is an oval in the SW to NE orientation. To the SW are 2 curving lines of stars; one curves to the WSW and onto the SE.  On the NE end of the oval is an a 5 dice pattern with a double star at the lower right position.  To the N of the cluster is a semicircle of 6 stars, concave to the cluster.  The star field is densely populated.

stack of 7 x 120 seconds, gain = 400, chip temperature = 0 C, dark frame corrected

I noted the guiding was much better on this target but still not great.

H 41-1, NGC 6514, Messier 20, The Trifid Nebula
A beautiful red nebula with dark lanes running through it.  Some faint blueish nebulosity (a reflection nebula) is visible W of the main red emission nebula where a bright star resides.    The star field is densely populated.  The main nebula is roughly circular and quite large.  I've seen this object before and imaged it with my Mallincam, but I've never seen it in this detail.  Luckily the guiding held the stars quite round for a stack of 11 x 3 min. The best looking image I've taken with this ASI071MC-Cool camera.  I didn't have a dark frame for 0 C, so there is some lightening along the bottom of the frame due to amp glow.
stack of 11 x 180 seconds, gain = 400, chip temperature = 0 C, no dark frame correction

This object is quite bright (apparent magnitude of 6.3) such that even a single 180 second exposure yields a reasonable image.
single 180 second image, gain = 400, chip temperature = 0 C, no dark frame correction


I shut down at 0243.

May 6, 2017
Came out at 2030 on a nice clear night. Hope to catch Jupiter and the GRS before it gets too close to the moon. Will be my first attempt at planetary with the ASI071MC-COOL camera. Set up at prime focus again with the Lumicon DS & Badder UV/IR filters on.  This setup yields a Field of View (FOV) of 40.4 ' x 26.8'.

I took several hundred images of Jupiter and stacked them in Registax, but the stacked images were no better than the singles.  The seeing just wasn't good enough for detailed planetary imaging.  I'll have to try again on a better night.



Resumed my Herschel 400 project. Camera still at prime focus with both filters in place.

H 19-6, NGC 5897
A GC with many discernible stars in the core.  Most stars in the core are of similar size but a few are larger.   The GC is roughly circular.   It resides in a densely populated star field with 1 bright star to the W of the GC.  To the SE of the cluster is a convex semi-circle of stars. 
Note the histogram on SharpCap couldn't be balanced so it is a bit greenish and lacking in red.  I haven't had this issue before.  Possibly influence from the near full moon.

stack of 7 x 3 min, gain = 400, chip temp = -10 C, dark frame subtraction

At 2327 readings are 57 F, 88% humidity, no wind. Sky Meter reading = 17.72 with a > 50% moon just past zenith.

H 280-1, NGC 6217
A small (approximately 3') galaxy in the FOV.  It appears to have a strong bar running NW to SE with a bright star just SE of the core.  No detail is discernible in the halo A well populated star field .  There is an asterism to the WSW of the galaxy that resembles the triangular shape of a pine tree.
stack of 10 x 3 min, gain = 400, chip temp = -10C, dark frame subtraction

Due to the size of this object, it would be better to use a barlow, but I doubt my seeing would have supported such magnification.  Stacking and cropping and then inverting the image, the shape of the galaxy is better viewed..
stack of 10 x 3 min, gain = 400, chip temp = -10C, dark frame subtraction, cropped & inverted

With NGC 6217 I'm still having a green hue to the images in SharpCap. I'm able to adjust in AstroToaster but I'm curious why this is happening.

H 215-1, NGC 5866, Messier 102
My observation matches the NGC 5866 pics and description in Wikipedia and other online sources but differ from what is in Deep Sky Planner and the DSS pic.  An edge on galaxy with a bright core region on both sides of the dust lane.  The galaxy is surrounded by 2 bright stars, one to the E and one to the W of the NW edge of the  galaxy.  The galaxy is in the constellation Draco and lies 50 mly from earth.

stack of 10 x 3 min, gain = 400, chip temp = -10 C, no dark frame subtraction
crop of the above image


H 195-2, NGC 6287, Melotte 163
A tight GC with a bright core.  Many individual stars are discernible around the core.   While the GC is circular, there are more stars to the NE & SW with fewer on the NW & SE sides.  The GC is in a very dense star field so its boundaries are had to determine.  It lies at a distance of 30,300 ly from earth.
stack of 7 x 3 min, gain = 400, chip temperature = -10 C, no dark frame subtraction



Shut down at 0211. The equipment worked well except for the greenish color hues apparently due to the full moon.

May 25, 2017
Tonight is clear and low (for SE LA) humidity and the new moon, so I had to come out for awhile.  Set up the ASI071MC-Cool at prime focus again with the Lumicon DS & Badder UV/IR filters on. This setup yields a FOV of 40.4 x 26.8 arc min.

My laptop is a Dell Inspiron 1764, CPU I3 M330, 2.13 GHz, RAM 4 GB, HD 454 GB, OS Windows 7 64 bit Home .  The USB ports are all USB 2 while the camera is USB 3.   I'm still having trouble with dropped frames and partially loaded images.  This is very frustrating, especially late at night.  I had the Turbo USB speed in SharpCap set at 40 but after some experimentation I increased it to 100.  With the Turbo USB at 100 I didn't suffer any dropped frames although I did have several that only partially loaded into SharpCap. Not sure if that is a camera or SharpCap issue.

H 165-1, NGC 4151
A small (~ 5') circular galaxy with a large bright core.  The halo extends 2-3 core diameters in all directions. There is no structure evident in the halo.  The galaxy is bounded to the E & SW by 2 stars of similar brightness & size.  There is a large reddish star to the S.  There is a smaller elliptical galaxy to the NE of NGC 4151.  It has a bright core and the halo extends 2 core diameters to the E & W and 3 core diameters to the N & S.  No structure is evident in the halo.  Unfortunately the images only partially loaded into the computer - ARGH !@#%&*#$  Will have to image this object again.


H 176-1/ H 177-1, NGC 4656/4657, The "Hockey Stick" galaxy
An intriguing galaxy that is long and slender running NNE to SW.  It is broader and fainter on the SW end and on the NNE end  the galaxy is bent NNW, hence the name "hockey stick galaxy".  The deformation is due to interaction with neighboring galaxy NGC 4631.  The Hockey Stick is slightly brighter near the middle but there is no discernible core. There is what appears to be a star near the middle SE side.  In the NE half there is a bright nodule at the point that the galaxy's "arm" bends N.  The star field is relatively spars in the immediate vicinity of the galaxy but there are stars surrounding it.
stack of 8 x 3 min, gain = 400, chip temp = 0 C, no dark frame subtraction, cropped


I didn't guide on NGC 4151 and yet the images looked fine. I did guide on NGC 4656 and the guiding was good, no spurious peaks.  At 2301 the sky meter reading was 18.96. It is 66 F and 83% humidity. A nice night considering it is nearly June. Shut down at 2310.

May 26, 2017
Came out a little before 2100 on a clear dark night with unseasonably dry conditions. I cleaned both filters well before this session to hopefully avoid the distortions observed last night. NOTE: this did work as the textile pattern was not observed even when greatly stretching the data.

I had to rebuild the mount model as I accidentally hit cold start on the Gemini hand controller– argh ! Amazing the download speed with the TURBO USB set to 100%. Rarely does an image go beyond a second or two past the exposure time.

Returned to NGC 4656 to capture a better image the first 3 min image was dropped - @@*&#%! Second image came up with a large black spot in the middle of the FOV ! Cooler is at -10, so I backed off the cooling to 0 and then 5 C. I had cooled the sensor down very slowly, irritating the difficulties I'm having with this.

I couldn't get to NGC 4656 without the camera coming too close to the pier, so I changed to M 57. The black spot has gone as I had warmed the camera to 5 C. I tried cooling it back to -5 and the spot returned so I went back to 5 C. I captured 2 light frames and then lost the next 5! Very frustrating! I don't know what to do about this other than get a laptop with a USB 3 input and hope that resolves the issue. I collected 10 light frames and 5 dark frames.

stack of 10 x 3 min, gain = 400, chip temp = 5 C, dark frame subtracted in AstroToaster


At Turbo USB = 100 I still see some redish lightening at the bottom of the frame, but not as bad as it was with Turbo USB = 40.

At midnight the sky meter reading was 18.82. It is 72 F & 99% humidity. Much more humid than last night. Clouds are gathering in the west.  Shut down for the night.

Saturday, August 12, 2017

April Observing Report


April 6, 2017
A cold front came through yesterday. Last night was clear and dry but tonight is even better EXCEPT for the nearly full moon looming overhead. Came out at 2000. Set up the ASI071MC-COOL at prime focus with the Lumicon DS filter. I was able to slowly drop the camera's temp to -20.

Synched the model on Dubhe and went to M-109 and started taking 60 second exposures at gain = 400. Frustratingly the camera / computer is still dropping 30 – 50% of the frames! A 60 sec exposure put the light curve maxima at only 15%, so I upped the exposure to 120 sec. Dropped about 7 frames in a row, very frustrating! I gotta change the wiring setup. I'm wasting too much time waiting on frames. Finally got an image and the 2 min exposure moved the luminescence to nearly 30%.

I was using a long active extension USB cable through a USB 3.0 powered hub to connect the camera to the computer. I removed the powered hub and the USB 3.0 extension cable. I hooked the StarShoot guider cam into the ASI071MC-COOL hub and ran a USB 3.0 cable from the ASI071MC-COOL to the laptop. Downloads are much faster and much fewer dropped frames at first with 30 second frames. When I upped the integration to 2 min, still there are too many drops ( nearly 50% of 2 min frames were dropped). Very frustrating. When I finally started imaging the M-109 the image contains an ice crystal, a lot of fogging, and a textile pattern!


I turned the cooling off and after a few minutes the ice, fogging, and textile pattern disappeared. I turned the camera's cooling to -10 C. As M-109 was approaching the meridian so I changed targets to M-101. At 2315 the ambient air temp is 54 F (12.2 C) with 63% humidity and the skymeter reading is 15.0 at the zenith due to the > half moon that is just past zenith. Pointing the skymeter towards Ursa Major the reading is a much more respectable 18.0.

Messier 101, NGC 5457, in Ursa Major is 21 million light years from earth. The face-on spiral galaxy is estimated to contain 1 trillion stars! Started imaging M-101 and got 5 x 120 second frames in and stacked in AstroToaster, looking pretty good. Then the camera / computer dropped the next 10 frames - ARGH !!


The image adjustments in AstroToaster are pretty good but I have to learn the interactions of the controls. Also I need more frames to bring out the detail in the arms. The object is getting too far to the west and into the higher light pollution region of my skies. So further frames will have to wait for another observing session. Shutting down at 0050.

April 8, 2017
Came out at 2100 to a beautiful night. Clear with no star twinkle, but a full moon sitting high in the sky. The temp is 63.3 F with 71% humidity and a dew point of 54 F. A slight occasional breeze. I set up the camera the same as last night: at prime focus, Lumicon DS filter, and gain = 400. I'll stick to -10 C on the camera cooler to hopefully avoid the textile pattern I saw at – 20 C. I still have the camera on a USB 3.0 cable direct to the laptop and the autoguider in the hub of the ASI071MC-COOL.
Cooled the camera down to 0 and held for 10 + minutes. Found the mount was parked slightly East in RA, so I had to reset counterweight down and now I'll have to rebuild the model; Arturus, Spica, Mizar, Denebola, Vindemiatrix, Castor, Capella, and Alphard.

I started out pretty good with the fast 8 sec frames while building the model, but when I went to 60 s frames the time to download got longer and I started dropping frames. I changed from RAW16 to RAW8 but it froze the SharpCap program. After several minutes of the program not responding, I killed it and restarted. Resuming my Herschel 400 project.


H 34-1, NGC 5248
Found that an exposure of 90 sec gave a maximum on the histogram at 40%. A little high but I'll go with it. I got 6 frames stacked, but dropped 4 so far. Seems like it gets into a mode of dropping frames, now I'm at 6 good frames & 8 dropped, so I've dropped the last 4 frames in a row. Finally got 19 good frames on this object.


This object is a face on spiral galaxy with a prominent arm on the N trailing back to the W and another arm on the S trailing back to the E. Apparent size is ~ 3 x 1.5 ', I'm missing the outer arms in my images. There are hints of inner tighter arms around the center. The center is not overly bright and elliptical running NW to SE. The galaxy is in a nice star field of 19 similar magnitude and size stars and many other fainter ones.


H 9-6, NGC 5466, Melotte 124
Went to NGC5466, a GC in Bootes. Set the exposure to 90 sec which gave a histogram curve maxima of around 27%. The images are very washed out due to the full moon.  The camera is still running at a gain of 400 and the chip temperature is -10 C.

This is a loose GC about 10 ' in diameter. The GC is roughly circular with a linear string of 5 stars on the NE corner. The star field is relatively sparse with no large or bright stars in the FOV. The GC is not saturated in the core. Many individual stars are seen.
I've cropped off the bottom 10% of the image due to amp glow.  Use of dark frames will eliminate that but for now this camera provides such nice fields, a little can be sacrificed without harming the image.

At 0004 it is 54 F and 88% humidity. The skymeter reading was 17.08 with the full moon near the meridian.

H 99-1, NGC 5557
This is a small (2.4 x 1.9 arcmin) galaxy in the constellation Bootes.  It is 132,700,000 light years from earth.  At 2 min exp yielded a light curve peak @ 31%. The galaxy is quite small at 2.4 x 1.9 ' but zoomed in my image is similar to that from the Deep Sky Survey (DSS). I captured 11 frames and then I stopped.

This is a small face on galaxy with a bright core that is slightly elliptical, while the visible halo is nearly circular. The diameter of the halo is roughly 3 core diameters. There is a bright star in the halo at the ESE position. The star field contains several bright stars that are nearly as big and bright as the galaxy's core. 


H 189-1, NGC 5676
NGC5676 will be the last target for the night. A 2 min exposure put the apex of the light curve at ~ 28%. I note that the bottom of each image contains a bright streak across the frame. Not sure if this is amp glow or what. I got 7 frames and it dropped 3 – ARGH !

A spiral galaxy inclined about 45 degrees and tilted towards the earth at a shallower angle. It is rather small. The core is barely more luminous than the halo. No discernible features from the halo. The galaxy is in a nicely populated star field with 50 or more stars. Two stars are rather large, at least larger than than the galaxy center.


I noted that the guiding graphs look terrible but the images are reasonable. I need to work on the polar alignment , balance and other causes of bad tracking. I shutdown for the night at 0204. Note the camera ran all night at -10 with no perceptible freezing of the sensor.  

April 14,2017

I returned the ASI071MC-COOL under warranty for replacement. There have been at least 2 other reports of similar issues on the ZWO forum.   ZWO is recommending people clean the sensor with alcohol, but I declined in favor of a replacement. Hoping the replacement will be here in time for the Deep South Spring Scrimmage. In the interim, if it ever clears up, I'll use my Mallincam.

April 20, 2017
Received my replacement camera today.  Came out a little after 8 on a clear, warm night. Setup the ASI071MC-COOL at prime focus with the Lumicon DS filter. Have the camera on a USB 3.0 cable direct to the laptop and the autoguider in the hub of the ASI071MC-COOL. Setup SharpCap for RAW16 color space with FITs files, no binning. Cooled the camera to 10 C and turned on the dew heater. After 20 min turned the cooler down to 0 C and then down to -10 and finally -20.  The camera got to -19 C but that's as cold as it could go.

H 186-1, NGC 5195, Messier 51b
Got a nice image of the whirlpool galaxy (NGC 5194, Messier 51a) and its companion, the smaller NGC 5195.   This galaxy is 25 million light years from earth in the constellation Canes Venatici.   Used  AstroToaster to live stack and adjust the images.  AstroToaster appears to be a better stacking program than SharpCap and it has, IMHO, better image adjustment tools.  The image is 11 x 120 seconds at gain = 400 with no dark frame subtraction.  

I did adjust the levels to brighten the image and improve contrast in GIMP 2.8.22.  

Messier 13, NGC 6205
Went to M13 and caught some nice images of The Great Globular Cluster in the constellation Hercules.  The image is 12 x 90 sec exposures at gain 350 and no dark subtraction.   The camera was running at -15 C.


Messier 57, NGC 6720
A little after 0200 I went to M57 (the ring nebula) and started to capture images and the image looked foggy with a center circle that was darker. I suspect this was from extended operation of the cooler at near 100%. I turned off the cooler until the chip reached near ambient (15 C) and then turned the cooler on again to 0C. After a few minutes I lowered it to -10 C. After a few images the dark circle reappeared at -10 C.  Captured images of the ring with AGC 400 & 3 min exposures. I noticed star trailing and the PhD graphs showed some big spikes in RA, both + & - . Image shift is severe at this point. Not sure what's happening. The mount is not giving any errors.

Interesting the image is black & white as it had color in SharpCap.  Shut down at 0303, will look at this tomorrow.
April 24, 2017

Came out a little after 2000 on a cool (for late April) and relatively dry night. Setup the ASI071MC-COOL at prime focus with the Lumicon DS filter. Have the camera on a USB 3.0 cable direct to the laptop and the autoguider in the hub of the ASI071MC-COOL. Setup SharCap for RAW16 colour space with FITs files, no binning. Gain set at 300 tonight to start. I want to experiment with different gains to determine the impact on the light curve & noise. Cooled the camera to 10 C and turned on the dew heater. After 20 min turned the cooler down to 0 C.


At the end of last session I experienced some significant drift that overwhelmed the guider. I wonder if the mount slipped on the azmituh or altitude locks. Will check that first. Went to Alphard in Hydra. Started drift and after 10 min there is drift up but nothing left or right. I'll take that as a good sign and move to a star in the East. Went to Zubeneschamali (Zubenesch) in Libra just above the E horizon. After 5 min there is drift downward ~ ½ star diameter, but not left or right. From what I've read about drift alignment, up & down drift is not a concern. Seems it should be but I'll have to read more on this later. For now I'll get started observing.
I checked the focus with SharpCap's Bahtinov mask tool. It is quite nice and helpful. Focus achieved at 34.5 mm.

On NGC 5689 a 2 min exposure at 300 gain yielded a light max of ~ 2%. A 3 min exposure yielded an ~ 7 % max.  Took a few more to populate the below table.

gain
exposure time
light curve max (%)
300
120
2
300
180
7
350
180
14
350
120
8
400
120
15,15
400
180
22

Other than the first table entry we see that increasing gain by 50 will increase the  light curve maximum by approximately 50%.  Increasing the exposure from 2 to 3 min (a 50% increase) increases the light curve maximum by a variable amount (250%,  75%, & 46%).  I should have captured the amplitude of the light curve at maxima, but failed to do that on all the tests.  Something to try another time, but this provides some insight into the system's response to varying exposure and gain.

At 2225 it is 58 F with 96% humidity and no wind. Sky meter reading is 18.99.

H 188-1, NGC 5689

A small faint (mag 11.9) galaxy in the constellation Bootes that is angled away from the earth.  It is approximately 116 million light years from earth.  The core is large and bright but no details are visible in the halo.  The star field is pretty well populated and there are 3 other galaxies in the FOV; NGC 5682 (mag 13.9), NGC 5683 (mag 14.8), and NGC 5693 (mag 13.6).  The image is 9 x 180 seconds at a gain of 400 gain.  The amp glow along the bottom of the frame is evidence that no dark subtraction was employed.


 H 195-1, NGC 4111 
The camera cooling is holding steady at -10 C with no visible artifacts in the images and at 19% power.  The object is a near edge on galaxy with a bright core in the constellation Canes Venatici.  The halo is approx 3 core diameters in radius and is oriented NW to SE.  No detail is visible in the halo.  There is a bright, large star to the SW of the galaxy.  There are 3 other galaxies in the FOV. Two are SW of NGC 4111; NGC  4117 (mag 13.4)  and 4118 (mag 16.0).   NGC 4109 (mag 13.3) is  NE of NGC 4111.  The image is 6 x 180 seconds at gain 400.  


H 701-2, NGC 6207
A small faint galaxy with a smallish core that is rather dim.   There is no detail evident in the halo.  The halo radius on the thin side is about 1 core diameter.  In the long direction it is 3-4 core diameters.  The galaxy is in a well populated star field.  There is a large star just off the FOV to the E.  The DSS image shows more of a molted appearance, but I don't see that in my image, which is 6 x 180 seconds at gain = 400.

At 0046 the temp is 57 F with 96% humidity and a sky meter reading of 18.99

H 759-2, NGC 5907
This will be the last target of the night. Still gain 400. PhD started giving me warnings about max RA duration is preventing PhD from making corrections. Not sure what caused this, likely the part of the sky I'm pointed at. Images have significant star trails. To complicate troubleshooting, the camera / SharpCap is posting partial images. The trailing stopped after a couple of minutes without any intervention by me. Not sure what to make of it. The stars are now nicely shaped starting in image # 4.   I noticed in image 3 of NGC 5907, the image has a dark circle like dew on the sensor. Raised the temp to 0 and then to 5 C.  This dew issue continues to plague me.

A large edge on galaxy in the constellation Draco.  The galaxy is oriented NW to SE.  The core is barely brighter than the surrounding halo.  The star field is nicely populated with many similar size & brightness stars.  The image is 7 x 180 seconds at gain = 400.

Shut down at 0145.


April 25, 2017
Around 10 am I installed the auxillary desicant tabs in the ASI071MC-COOL. Hopefully this will avoid the dark circle in the images like I experienced late last night.

Came out a little after 9 pm on another coolish (66 F, 90% humidity) clear night with a light breeze. Created a new PhD dark library for 3 – 6 seconds with 10 exposures each. Hopefully this will help reduce the noise and improve the S/N on the guide stars. And it did, I went from a S/N of 12 to 46 with the new darks.

Took a new series of darks on the ASI071MC-COOL at 180 sec & gain 400 @ -10 C as RAW16 FITS. Hopefully it will eliminate the glow along the bottom of the frame.

H 42-4, NGC 4631, Caldwel 32, "the Whale & Pup (NGC 4627)
The guiding is poor – swinging from -2 to +2” on both axis with occasional larger swings in RA. I saw this last night when the scope was pointing near the zenith. I'm not getting any Gemini errors but perhaps I'm not sufficiently balanced. The tracking settled down and I took 10 images of 180 sec each and stacked at gain= 400.  The dark subtraction did help to remove/reduce amp glow.

An edge on galaxy in the constellation Canes Venatici that is thicker on the S end than the N.  There is no discernable central core but there is a brighter region just to the S and W of the center of the visible galaxy.  The galaxy is oriented NNE to SSW.  Also visible in the FOV is a companion galaxy (NGC 4627, "the pup").  It is a small roughly circular galaxy located just W of the center of NGC 4631.  These galaxies are located in a nice star field with a loose grouping of over a dozen bright stars to the WE of NGC 4631.  
Cooler is holding -10 C well at 22% power. No artifacts noted on the images thus far.   At 2340 it is 61 F with 94% humidity and a sky meter reading of 18.92.

H 40-6, NGC 6171, Messier 107
I wasn't able to get any of the targets around the N pole, so I moved back to the E to NGC 6171 in the constellation Ophiuchus.  I found it easily and cooled the camera back down to -10 and I got the circle back !!!.  Had more difficulty guiding with wild RA swings. I had recalibrated PhD before this. Not sure what is causing this, but it is screwing up lots of images!

After a few minutes the tracking settled down somewhat (I didn't do anything) and I was able to capture eight images of NGC 6171 with nice round stars. The computer dropped a few frames which prolonged the process and raised the aggravation level.

Note on this GC (NGC 6171) a 3 min exposure with gain = 400 yielded a light curve with the max at just under 20%. So even with reasonably bright (mag 7.8) objects it takes ~ 3 min exposure to capture. Dimmer objects like nebula will likely require me to take longer exposures.

This is a nice GC in a rich star field.   The core of the cluster has many discrete stars visible in a roughly circular grouping.  On the N side of the GC  there is a line of stars running NE to W.  There are 5 larger brighter stars in this FOV.

Shutdown at 0156.

April 30, 2017

Came out at 2330 on a windy night after a stormy day. Clouds are clearing but still prevalent. Checked scope balance and found it fine in RA & Dec. I did find the W azimuth lock blot a bit lose and tightened it. Not sure if that accounts for the poor tracking when the scope is near zenith.   I'm using the ASI071MC-COOL at prime focus with the Lumicon Deep Sky filter + a Badder UV/IR cut filter. This is my first time using the UV/IR filter on this camera.

I captured a few images of the Ring nebula (M 57).   Images are 180 sec, gain 400, -10 C, dark frame subtracted in SharpCap. Intermittent clouds are disrupting some images & affecting the guiding. I'm noting a small dark circle near the bottom of the image that I haven't seen before and also an arc to its NW. I suspect these may be from the UV/IR filter.  Focus looks a bit off.   Certainly not my best image of this iconic object.

Sky meter reading @ 0232 = 19.10, 59 F, 83% humidity, with only light breeze now. Most of the clouds have cleared except for some low in the east.

I dropped 3 images out of 10 taken on M57, very frustrating! I hate to spend the money on a laptop, but that may be the only solution. Also the histogram colors were not well centered with red to the left of the white and green & blue to the right.

It is after 0230 and the mosquitoes are irritating me, so I'm shutting down.

Monday, July 17, 2017

March Observing Report

March 15, 2017
I setup with the same optical train as last time; the VRC 10", with the Mallincam 2” 0.75x Focal Reducer and the ASI071MC-Cool. The 2” Lumicon Deep Sky filter is on the front of the FR. I set the camera cooler to -10C and turned on the dew heater. The camera gain is set at 400 to minimize exposure times.  I opened the roof to a cool, clear night.


I started off the night with Jupiter.  I've never had much success with planetary images.  I blame it on the high humidity and the resultant poor seeing in SE Louisiana, but I'm sure my technique is also to blame.  From what I've read I might do better stacking planetary frames in Registax.


Started the autoguider and began an image of the Orion Nebula. Wow, at 30 & 60 second images were wonderful, albeit noisy until several are stacked. Sharpcap hung while changing the exposure duration.  The autoguider keeps the image rock steady. This is the first time I've captured the arching structure of M43 in my images.  The below image is 6 x 60 seconds at gain of 400.  The Trapezium region is blown out.  A larger number of shorter exposures would likely yield a nicer image.


Messier 42, the Great Orion Nebula, is approximately 1,344 light years from earth.  The region includes clouds of neutral and ionized gas, dust, star clusters, and reflection nebula.  The much smaller Messier 43 is 1,600 light years from earth and is separated from Messier 42 by a dark dust lane.

I noted that when stacking in SharpCap, that many frames appear to be dropped. I went in the house to get coffee and was gone 10 min while stacking 1 min images. When I returned it showed only 2 stacked!  I think this is because in the stacking routine I asked it to align the frames. I'm not sure why SharpCap was rejecting so many frames.  That coupled with frames that failed to even load greatly slows down data collection.  I turned the align feature off and it is then stacked fine but some frames were still dropped.

At 2240 the temp is 42 and humidity is 80%. Sky meter reading is 18.60. Sky looks very clear but not my best sky meter reading.  Shut down at 2346.
==
March 18, 2017

Came out at 2100 on a nice night with scattered clouds, 67 F, 96% humidity and no wind.  I set up the ASI071 at prime focus with 4” of focuser rings and no extensions or focal reducers. I do have the 2” Lumicon DS filter on the end of the camera's nose piece.  I achieved focus at 35 mm on the focuser with this setup.  Note for this setup I had to significantly adjust the scope on the mount's dove plate to achieve balance

H 205-1, NGC 2841
Is a galaxy in the constellation Ursa Major (the big dipper) and it approximately 46 million light years from earth.  The galaxy is tilted away from us by 20-30 degrees.  The galaxy is surrounded by a nice star field.  Four minute single images didn't tease much structure out of the galaxy.  I need to stack but my camera is close to hitting the mount so I can't go any longer on it.


I noticed that with the ASI071MC-COOL camera in the focuser with the writing upright, the mount directional arrows work in reverse from the Mallincam.  I uploaded a single 240 second image (gain = 400) of NGC 2841 to astrometry.net to measure the field size.  It reported 40.5 x 26.9' with a pixel scale of 0.491 arcsec / pixel. This measurement allows a calculation of the reduction provided by the 2" 0.75x Mallincam Focal Reducer was 0.771.   This compares very favorably to the 0.770 observed reduction previously measured with my Mallincam Extreme.

 The astrometry.net report also showed that "up" is at – 88 degrees so the camera's orientation is a bit off.  I suspected based on the mount directional keys that it would be closer to 180 degrees.  In the future I'll mount the camera in the focuser with the writing on the camera's back upside down to reverse the slew direction to what I am accustomed to.


At 0043 it is 63 F and 98% humidity. Starting to get dew on some surfaces.


H 43-1, NGC 4594, Messier 104, The Sombrero Galaxy
A very nice galaxy nearly edge on, turned towards us by just a few degrees.  It has a bright core and the full top half of the galaxy is illuminated.  The galaxy is oriented N-S and a prominent dust lane is evident.  It appears to be approximately 8 ' long.  The galaxy is in a rather sparse star field.

  The above image is a stack of 10 x 120 seconds at gain = 400.  Stacking done in SharpCap.  There is a little illumination (amp glow?) on the bottom of the image, especially on the left.  I'm running the camera at -10 C.  A longer exposure would have been better to pick up more details.

H 78-1, NGC 2985
This is a nice spiral galaxy in Ursa Major located 64 - 67 million light years from earth.  I took a stack of 5 x 240 seconds at gain = 400 and with the camera operating at -10C.  

I've been seeing issues with ice formation on the chip at temps more than the -10 C setting. However tonight I'm getting a big circle of dark hazy nature so I have to turn the cooler off to make it go away. This isn't a good thing as it hurts the image and increases the noise level. Perhaps I need to add the auxiliary desiccant tablets to the camera.

Since I couldn't discern any detail of the galaxy, I didn't count this observation towards my Herschel 400 project.  Similarly I tried H 168-1, NGC 3184 but had similar issues with distortion of the image.   At 0148 clouds rolled in and ended the session. Learned some more about the camera & SharpCap

March 23, 2017
Came out a little before 2000. It is clear with a slight breeze and 72 degrees with 88% humidity. I installed the ASI071MC-COOL upside down to match the orientation with the mount's controls. No FR, prime focus with the Lumicon DS filter.  After taking a few dark frames I noticed that the 
winds brought in clouds at 2026.   By 2200 the sky looked a little better with the sky meter reading was 18.43. Better than I expected with the clouds rolling through. It is somewhat clear now but high thin clouds are in parts of the sky.  As I've been hunting Herschel objects in Ursa Major, I decided to give Messier 81 a try with the new camera.

Messier 81, NGC 3031, Bode's Galaxy
The clouds held back and I got several 2 min exposures of M81. The raw subs were captured and included dark frame subtraction. The stacked exposure with 10 x 2 minute exposures (gain = 400, camera temp -10 C) looks pretty good but little detail in the galaxy's arms is evident.  This is a spiral galaxy about 12 million light years away


I had more issues with large dark circles forming on the images.  If I turn the camera's cooler off or at least set it to above 0 C, the circles disappear.  However they reform once I turn the cooler back on.   Clouds rolled in and ended the observing session at 2300 hours.
==

March 25, 2017
Surprisingly the skies are clear after heavy afternoon thunderstorms. The humidity is high so the seeing isn't great, but no clouds. Came out a little after 2000.  ASI071MC-COOL setup at prime focus with the Lumicon Deep Sky filter (2”). After about 30-45 min, I started getting the dark circle in the center of the ASI071MC-COOL's FOV. Cooling was on -10, so I turned it off and the circle disappeared.  At 2305 it is 62 F and 99% humidity with no wind and clear skies. Sky Meter reading = 18.92. Everything is wet!

H 160-2, NGC 3686
This is a small face on galaxy in the constellation Leo and is ~ 53 million light years from earth.   In the FOV with at least 2 other galaxies.  The image is 21 x 180 seconds at gain = 400.

The subject galaxy is nearly circular with a prominent bar running NS.  Off the N end there is an arm circling to the E and back around to the S.  From the S end of the bar is an arm circling W and back around to the N.  The second galaxy is a faint eliptical around 20 ' away to the ESE.  THis galaxy has no discerable core.  This is NGC 3691, a mag 12.4 galaxy that is 1.4 x 1'.   The third galaxy is also eliptical with a brighter core. It is ~ 15' to the NE.  This is  NGC 3684, a mag 11.4 galaxy that is 3.1 x 2.1 ' in size.  Galaxy cluster Abell 1264 is also in this frame but would require much more magnification to resolve.


H 21-1, NGC 3810
A face on spiral galaxy in Leo that resides approximately 50 million light years from earth.  The core is not overly bright.  Multiple 4 minute exposures was insufficient to pull out any detail.  I do note that the stars are a little elongated so apparently my guiding was lacking a bit.  Also the camera cooler was off as I was having issues with a dark circular region forming due to the high humidity.  The image is 8 x 240 seconds at gain = 400.  I'll have to try this object again to see if I can pull out any hint of the detail shown in the Hubble image.




March 31, 2017

Based on feedback from ZWO, I installed the auxillary desiccant tablets onto the camera a couple of days ago.  Hopefully that will dry out the air in the chamber housing the chip and avoid dew or ice formation.  They also advised to cool down the camera slowly.  I setup the ASI071MC-COOL at prime focus with the 2” Lumicon DS filter. I started the cooler at mild cooling 16 c and will stair step it down.


I tried to get M81 & 82 in the same frame but they were too close to the edge of the FOV, so I'll need to use the 2” FR to get both. For now I'll concentrate on M-81.  At 2318 sky meter reading was 18.94. Temp is 62 F with 96% humidity

Messier 81, NGC 3031, Bode's Galaxy
Decided to try this object again to see if I could pull our a bit more detail.  The image below is 5 x 360 seconds at gain = 400 and the camera is operating at -10 C.    The frames were stacked in SharpCap.  Uncharacteristically I used GIMP to adjust the brightness and contrast, which yielded an improved image. Perhaps I'll try using AstroToaster instead of SharpCap's to stack and adjust brightness and contrast next time.  I had no issues with dew or ice formation in the camera.



Poor tracking ruined my attempt at M-101.

Messier 13
Next I turned my attention to Messier 13 (NGC 6205), one of the finest objects in the night sky. It contains approximately 300,000 stars and resides 22,200 light years from earth. I stacked 11 x 60 second frames at -10 C and gain 400. I avoided blowing out the core, but the exposure needs to be a bit longer to reveal more stars.


I suffered a lot of dropped frames,  ~ 50% during this session.  Very frustrating.  Shut down at 0200