M20 Wide Field

The Trifid nebula, whose name means “divided in 3 lobes” is an amateur favorite. An island of HII region which is the red portion (HII regions are emission nebulae created when young, massive stars ionise nearby hydrogen gas clouds with high-energy UV radiation causing the gas to emit red light) , a blue “reflection “portion which occurs when light of the nearby massive blue stars reflects off of the dust, and a “dark nebula” portion which divides the nebula into its 3 lobes. There is also an open cluster of stars in the field. The Trifid is 5000 light years away toward the center of out galaxy, hence the very dense surrounding star fields and dust.

I completed my test of the Tak FS120 imaging capability and you can see the result below. I was pretty happy with it, especially considering the very modest set up I am using (see last entry) . For the full resolution image you can click on the thumbnail on the right side of the blog under “my astroimages”. I am looking forward to more projects with it!

Until next time. Thanks for reading!

Dr Dave

M20, the Trifid. Single raw image 5 minutes.

 

This is the fully processed result! 33 x 5 minutes or close to 3 hours of data. I tried not to overprocess it but to preserve the natural nebula colors and bring out the background dust behind the dense star fields.

Back at the Telescope

Can’t remember the last time I was actually “at the telescope”. Not with automation, executive programs, remote operations etc. However as luck or bad luck would have it I encountered another hardware failure on the now 9 month old Paramount. This time it was the PCB on the MKS 5000 control unit. So with my main imaging platform down I went back to basics. Back to the reason I came here in the first place. The dark sky! It’s still there. I happen to have a Tak FS102 refractor. This is a wonderful instrument. Let’s look at this for a minute. The FS-102 is one of the long discontinued Takahashi refractors. The FS series are some of the finest small refractors ever made yet supposedly for visual use only. Why is that? Did some “Dark Lord of Imaging” declare you can’t use it for that? Without going into a long treatise on refractive optics, let’s just say that the FS scope being a doublet lens design was replaced by the triplet lens designs (Tak TOA and TSA) which “supposedly” give better chromatic aberration correction which “supposedly” is better for imaging. Each wavelength of light coming through a lens “bends” or refracts at a different angle so without correction the red light comes to focus at a different point than blue, etc. Contemporary refractive optics (known as apochromatic using ‘ED’ or ‘extra low dispersion’ glass) were designed to correct for this and prevent what is known as chromatic aberration which appears visually as weird color fringes around objects. Apochromatic optics can consist of doublet lens or triplet lens designs.
But wait a minute. The FS is a fluorite doublet. Fluorite is not a glass. It’s a crystalline mineral and it has superior optical properties to glass , including very high transmission of light and low scatter. ‘FS’ stands for “Front Surface” meaning the fluorite element is on the front. It is true I obtained this scope mainly for visual use and the views are amazing here; strikingly better in my opinion than in my triplet William Optics refractor of similar size hands down. Outstanding crispness and color! I think it’s the best I’ve seen in a scope of this size. In my opinion if the scope gives you excellent optical performance visually, then why would that not translate to imaging performance? I decided to give it a try.
So under the incredible dark moonless night sky here at Orion’s Belt Remote Observatory in the Sacramento Mountains, with the Summer Milky Way coming in to full bloom over the horizon at about 10 pm, I set up the FS for an imaging session targeting an age old favorite: M20, the Trifid Nebula, in the constellation Sagittarius. The Trifid has everything in one package. It has an open star cluster, an emission nebula (the red portion), a reflection nebula (blue portion) and a dark nebula in the middle creating the trifurcated appearance. I have a small Tak guidescope mounted on the FS, just for occasions like this. I hooked up my Canon 60Da and connected the Lodestar X2 guide camera to the guidescope. I plugged the Lodestar into the guide port on my Celestron AVX mount and took about 3 hours of images! The steps were as follows:
1) Polar align the mount. I used Polaris and sighted it with a laser pointer. Pretty rough but adequate
2) Calibrate the mount. Most of the go to Celestrons do it the same way. Use the hand pad and punch in 4 stars, 2 on either side of the meridian. I put the Canon in “live view shoot” mode which is very handy because you don’t have to keep taking exposures to find the star you’re calibrating on. It is basically a video mode but very high sensitivity. It just works! I use the brightest stars out there.
3) Refocus. Once the calibration is complete I will focus on the last star. I use the live view mode and use the magnification function to blow up the star, then carefully focus until the star image is as small as possible. The FS focuser is very solid but it is not a dual Crayford style so you have to go slow.
4) Slew to M20. Take a 15 sec image and make sure the framing is what you want. In this case I had to use the hand pad to make small adjustments.
5) Finally you start the guiding process. I used PHD2 guiding software which is freeware and works with a number of guide cameras. Outstanding program! Very simple to use. I really was not sure what kind of guide performance this simple AVX mount would have but I was pleasantly surprised that it responds quite well to guide commands . It just works! All I did was plug the Lodestar into the port called “autoguide” and configure the PHD2 software. You pick a guide star on the screen and click on the guide button! Folks, it does NOT get any easier.
So that was it. Now you can be the judge! (see below) Honestly I think it did pretty well for a single 5 minute raw image! I will update you on the final result after processing etc. Couple of points. One is that you do need a flattener for this as you do for most refractors. I borrowed the one I was using for the William Optics which is identical diameter and close to the same focal length. The FS is an F8 where the WO is about F7. It seems to do the job as the stars are perfectly round to the corners of the image. Second point is you need to spend time focusing. There is no automation of this. This is just old fashioned adjust until it’s right.
Didn’t think this post was going to be this long but the night “back at the telescope’ was the most fun I’ve had in quite some time. So far I have not been the victim of any spells cast by the “Dark Lord of Imaging” !
Thanks for reading!

Dr Dave

Back to basics imaging set up! Tak FS 102, Canon 60Da with flattener, Lodestar guider, Tak GT40 guidescope, Celestron AVX mount

 

Ok so I’m not in the warm room! or in the astronomers quarters at the base of the hill watching it happen remotely. I am “at the telescope” under the glorious Milky Way while the images are being captured. I dropped the south wall down and did some binocular viewing during the session. This is astronomy folks!

 

M20, the Trifid. 5 minute raw image with the set up shown above.  A jewel in the stellar sea of the galactic center! You can see the edge of the Lagoon nebula in the lower right peeking through. Ok so I know it’s not a full res image. BUT at full resolution the stars are still round and not bloated. Can’t wait for the final result! Fluorite optics folks! That’s where it’s at …for refractors anyway 🙂

Morning coffee- Spring edition: Venus and the crescent Moon, a comet and a pair of galaxies

This kind of stuff never gets old! A crisp Sunday morning, a cup of hot coffee, and a glorious sunrise with our friends Venus, who is a morning planet now after passing through inferior conjunction,, and of course a waning crescent moon.

Spring hasn’t quite sprung yet up here on the Hill. This morning the temp didn’t quite break 30 degrees. Strange patch of high humidity came through last night and when I checked the scope after last night’s session there was frost on it! Had to throw out about 75% of the images as a result. But, we did get one hour’s worth of new data on a new imaging project, the galaxy pair M81 and M82. I have never actually imaged these together before. Looking forward to the finished result! Then to top it off I found one of this month’s binocular bright comets, PanSTARRS, making its way through Aquarius now. I caught a glimpse of it about an hour and half before sunrise. Not enough time to do a full imaging sequence but enough to see a tail! Comet Lovejoy, supposedly more impressive is just too low now for me to get a good look at it. We’ll have to revisit these next month perhaps!

Comet PanSTARRS (C/2015 ER61) just passed closest to Earth on April 19 at 109.5 million miles. It should continue to brighten up until May 10 when it reaches perihelion, closest to the Sun. This is just a 1 minute single frame uncalibrated luminance image taken with the 5″ refractor

New project! The galaxy pair M81, M82 are part of the “M81 galaxy group”. There is a third galaxy, NGC 3077 which is interacting with the other 2 gravitationally but not in this field. The interactions have stripped away hydrogen gases from all 3 forming intergalactic filamentary structures called the Integrated Flux Nebula, I hope will be revealed in the final image. This is a single raw uncalibrated 6 minute luminance image taken with the 5″ refractor. Note the vertical lines through some of the stars. This ccd is very sensitive and what is called non-antiblooming, meaning that for these stars the charge in these pixels have exceeded the saturation level and then start to fill adjacent pixels. The sensor is designed to allow for vertical shifting of charge but not horizontal. So yes, this is kind of an “accepted inconvenience” , which has to be processed out of the image at some point, in exchange for higher quantum efficiency and data preservation but perhaps a topic for another day!

 

 

Thanks for reading!

Clear Skies

Dr Dave

Official “first light”

After a fairly long course of gremlin battling (since October of last year!) I finally completed a full automated imaging project. Note this is “automated” but not “remote”, meaning I still have to go up there to turn everything on but once that’s done I can go back to the base house to do everything else. That’s the first step. Once we can do that fairly reliably, the next step is total remote operation off site. A lot to do before that!

Still trying to figure out guiding issues with CCD autopilot but we did get this done. It was a relatively short project, just over 7 hours and only 1 channel, Hydrogen alpha ,but a very interesting area that I had not visited before! SH2 249 is an emission nebula visible in the constellation Gemini. Currently March through May/June is really galaxy season and our equipment is not particularly suitable for that…yet! So this was a good initial target. Stewart Sharpless (Hence the designation ‘SH’) back in 1959 published a catalog of HII regions. What is an HII region? Here is the explanation (from Wikipedia):”An H II region or HII region is a region of interstellar atomic hydrogen that is ionized.[1] (H is the chemical symbol for hydrogen, and “II” is the Roman numeral for 2. It is customary in astronomy to use the Roman numeral I for neutral atoms, II for singly-ionised—H II is H+ in other sciences—III for doubly-ionised, e.g. O III is O++, etc.[2] H II, or H+, consists of free protons.) It is typically a cloud of partially ionized gas in which star formation has recently taken place, with a size ranging from one to hundreds of light years, and density from a few to about a million particles per cubic cm. The short-lived blue stars created in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds.” Probably the most famous of these is the Orion nebula, but there are many many others! This is one I discovered, never imaged before, designated SH2 249. The object to the upper right has been called by astronomers the “Jellyfish nebula” for obvious reasons. Equipment used is shown here. Right now we have a Tak 130 NFB refractor, SBIG STXL 6303 camera with self guiding filter wheel. 29 exposures with a hydrogen alpha filter, each 15 minutes long.

First operating platform from the new observatory. Takahashi TOA 130 NFB, Moonlite “Nitecrawler” focuser-rotator, SBIG STXL 6303E camera, Paramount MEII mount

 

HII region in the constellation Gemini (see text above). Taken with 5nm H-alpha filter. March 2017. Orion’s Belt Remote Observatory. See the images link in the right panel for full resolution version!

Thanks for reading!

Clear skies

Dr Dave

Across the valley

Had a chance to take a few days off from work to spend up at Mintaka Hill. My wife and I met a number of the neighborhood astronomers in our area. They live on both sides of the valley. I did get a lot done at the observatory. The focuser/rotator is operational and I have set up automation for the Tak refractor. We still have to figure out the roof remote operating system but have plenty of time for that. Meanwhile I paid a visit to Joe D.’s observatory. Joe lives across the valley from us and a little higher up. His passion is spectroscopy. I looked at his set up because I will be using some of the same equipment when it arrives in a few months from now. Anyway I had a chance to view my observatory from a unique vantage point as you can see! I guess we did clear a lot of trees!

Looking back across the valley to Orion’s Belt. B is the “astronomer’s living quarters”. A is the Orion’s Belt Observatory

Talavera night!

 

We begin the journey back into high resolution planetary imaging! This is a much different challenge. I have done some planetary work in the past with mixed results. The most important variable is seeing. To really get the details you want the atmosphere has to be like the “glass ocean” or like the ocean that is completely calm with no waves. I don’t know if that ever happens! The guys who are expert with this actually live near large bodies of water. Maybe that’s not a coincidence. The other problem is that planets are usually low in the sky for us here in mid northern latittudes so at these altitudes, usually less than 60 degrees the atmosphere is more dense. So tonight we are going to be at the telescope in the TSH (short for Talavera Space Hut) and let’s see what happens! Certainly we have the equipment to do it. I understand most folks are using SCTs for this but RC optics should work great I would think. After all that’s what the Hubble is using! We also have a great permanent mount, high frame rate USB 3 camera so no excuses there!

This video demonstrates the equipment we will be using for planetary imaging: AT12RTC scope, Celestron Skyris 132M usb 3 camera, Moonlite stepper focuser and of course our trusty Paramount ME mount!

 

In this video segment, the telescope is turned on, initialized and we are waiting for Jupiter to come up over the mountains!

 

In this video some of the basic functions of the program Firecapture are demonstrated. Use of ROI (region of interest) is explained. Live video of Jupiter as we begin the session.As it is for deep space imaging, video also should be calibrated for dust but the ROI function can also help.

 

In this segment we point out some additional features found in the Firecapture program. The image details are somewhat improved as Jupiter climbs a little higher in the sky

In this final sequence we are capturing an R-G-B sequence of Jupiter

Talavera 2.0!

What a difference a couple of years makes! Our community known as Talavera continues to grow like crazy along with the town of Las Cruces, NM. Along with huge growth comes increase in lighting and unfortunately the lighting is not exactly sky friendly. I am truly amazed in the 4 years I have been here the light dome from town has been steadily increasing to the point now where it is close to 50 degrees over the western horizon! Thankfully we now have Orion’s Belt Observatory in a dark site (for now), dedicated to deep space imaging and spectroscopy. So what to do with the Talavera Space Hut as we affectionately call it?

This is the equipment stationed in Talavera. An Astrotech 12″ f/8 RC scope on a Paramount ME and mounted on that is a William Optics GT102 refractor. The 12″ has a focal length of 2400mm. This is more than sufficient for planetary imaging.

I have thought about this for awhile now and what we decided to do was convert it to a planetary observing site. We can also do video astronomy for community outreach as we have in the past. Possibly narrow band projects etc but for now we have reinvented the Hut for the purpose of solar system observations. On Saturday March 4th I started this  transition with a full evening of solar system observing and what an amazing night it was for that! I think the images are self-explanatory.

We already have installed a stepper motorized focuser. The camera currently is a Skyris 132M video camera with manual filterwheel. The Skyris is usb 3 and capable of frame rates as high as 100fps

We started out with the Moon. We’re using the software Fire Capture and you can see some of the lunar surface there on the screen

The space hut is a small roll off structure, only 8 feet square and manually operated. It is located in our backyard here in Las Cruces

A very cool Venus apparition! The bright planet is rapidly swinging between us and the Sun as it goes through inferior conjunction and will soon swing around to the other side of us and the Sun to become a morning star! In the meantime it appears as a very thin crescent. This is a capture sequence with a blue filter.

The fairly well publicized lunar occultation of Aldebaran, the red giant star in Taurus, occurred on Sat night the 4th. I am not much of a lunar observer but I was aware of the time it was supposed to re-emerge and since I was lucky to be out there testing this equipment for its new role I decided to try and capture it! The star’s relative motion is very fast and I was just in time! This is a single frame at prime focus.

Finally there was Jupiter! I do have some experience with planetary imaging prior to moving out here so I do know what to do. Unfortunately it appears I will have to add some extension to the optical train in order to use any additional magnification so sorry the planet is so tiny but this is an LRGB image obtained about 12:30 AM MST. No transits or other phenomena were visible at that time but I think this is promising. The image is pretty clean and seeing was not superb so perhaps this is a good sign of things to come!

Not too bad for a first night of solar system observing!

Thanks for reading!

Clear skies,

Dr Dave