Saturday, January 31, 2015

Narrowband Fun

There are some things, like most all reflection nebula, and most galaxies, that must be shot in wideband luminance. This requires good dark skies to get the most of LRGB imaging. I'm sure this is not the case, but sometimes it just seems like we have cloud cover and rain around New Moon, then it gets clear with a big bright Moon in the sky. This is when its nice to have narrowband filters.

Narrowband filters cut through the natural light pollution of the Moon, as well as man made lighting common in big cities and large towns. Even here in the country, we have neighbors on all sides with bright night lights in their yard that can be a pain to deal with. I have had my Astrodon 5nm hydrogen alpha filter for a good while, but have recently purchased the Astrodon oxygen (OIII), and sulfer (SII) filters. The first time I used these three filters I got a very bad SII signal because I shot with it very close to the full moon. Using these filters are perfectly fine to use with a full moon but I would suggest choosing a target at least 30 degrees away from the Moon when it is this big and bright. Because the SII signal was bad, and the fact that I also added RGB to my Tadpoles (IC 410), I consider my recent Rosette nebula to be my first true Hubble Palette image.

The classic Hubble Palette image, or SHO, maps the colors as Red=SII, Green=H-alpha, and Blue=OIII. First lets take a look at the different components that each filter yielded.

Here is the Hydrogen Alpha image.


Here is the SII.


And here is the OIII.


As you can see, each filter highlights a different component of the nebula. By mapping these images into the color channels as descibed above, I came up with my first true Hubble Palette image.


These were all shot with my new William Optics Star71, a 71mm 5 element apochromatic refractor operating at the native focal ratio of f/4.9 and 348mm focal length.

You can also map these colors in HSO for a more red tone which is considered more natural looking. I tried it in this palette but the colors came out very purple to my eye instead of red. So I decided to try a blend of the different components to see what I could come up with. For this next image I used a blend of 65% SII and 35% H-alpha for my Red channel, for Green I used OIII, and for blue I used a blend of 65% OIII and 35% H-alpha. Since I did not use H-alpha as a dominant channel, I lost some of the fainter outer regions but came up with a color theme that I felt was very pleasing to look at.


November and December was just awful this winter for imaging, but January was very kind. I'd like to share my images from this month here.

First up, and shot over the nights of Jan 6th and 7th, was "First Light" for my WO Star71. This is commonly called The Ghost of Cassiopeia. It is a combination of H-alpha and RGB. The dominant star in the image is gamma Cas.


On the night of January 8th I decided to take aim at a solar system target, Comet Lovejoy C/2014 Q2.


On the nights of January 9th and the 13th, I shot one of the all time favorites, the Horsehead and Flame nebula. This one is also a combination of H-alpha and RGB and was shot with the Star71.


January 16th and 17th was spent shooting the Witch Head nebula, a reflection nebula just off from the bright star Rigel in the constellation Orion. This one is LRGB with the Star71. You can certainly see where this one gets its name. The bright flare in the upper right was caused by Rigel.


Early on the morning of January 17th, after the Witch Head was too low in the west to image, I slewed to the constellation Virgo and gave this great cluster a go. I was able to capture about 3.3 hours of luminance data on this target before the Sun started coming up. The dominant group of galaxies is called Markarian's Chain, but there are MANY galaxies scattered throught the image. I hope to add some color to this one in the coming months.


After then spending a few nights gathering the narrowband data on the Rosette I changed out scopes from the Star71 to the TS 107mm triplet and captured M78 the nights of the 20th and 23rd. M78 is mostly a reflection nebula and was shot in LRGB.


On the nights of the 20th and 24th, I was able to capture this wonderful trio of galaxies in Leo, appropriately called the Leo Triplet. M65 in the top one on the right with M66 below it. On the left is NGC 3628. I was able to get some of its faint tidal tail that stretches down to the bottom of the image.


The nights of the 24th and the 26th were clear enough to get my final image of the month, the Cone nebula. This nebula is also known as the Christmas Tree Cluster and NGC 2264. The Cone nebula is a huge HII region located very near the Rosette nebula between the constellations Orion and Gemini. This one was shot in H-alpha and RGB.


As you can see, January was a great month here for imaging the stars. After just one image in November, and one in December, this was a welcome change. So 2015 is certainly off to a great start. If the coming months yield half as much imaging time it will be a great year at Little Piney Observatory.

For a closer look at these images you can click on the pictures. Or to get an even bigger and better view of these and many more images, please see my gallery on Astrobin.  http://www.astrobin.com/users/rflinn68/

Clear skies everyone!

Tuesday, December 30, 2014

Another Year of Learning

I feel that I made some big strides in 2014. I have learned a few more tricks in Photoshop, and also purchased PixInsight this year. I still have much to learn with PixInsight and there are always improvements to be made and new things to learn with Photoshop. Instead of the old "shoot from the hip" mentality on the processing end of things, I think I finally have developed somewhat of a workflow for both narrowband and LRGB images that I try to follow. I think this is very important as I work on being consistent from image to image and try to develop my own style.

I have also been blessed enough to do a lot of upgrades this year. I was able to upgrade from my Gary Honis modified DSLR to the SBIG STF-8300 monochrome CCD camera. To go with the new CCD camera I was also able to get the Starlight Xpress 7 position 36mm USB filter wheel and load it with Astrodon Gen 2 LRGB and 5nm Hydrogen alpha, OIII, and SII filters. Along the way I also put the Orion 50mm mini guidescope and StarShoot autoguider on the shelf and replaced them with the Starlight Xpress off-axis guider and QHY5L-II guide camera. These have all made a huge improvement in my images.

In September I was able to upgrade my mount. Some would not call going from a mount rated to carry 50 lbs (CGEM DX), to a mount with a capacity of 44 lbs (Atlas Pro) an upgrade. For me this has made a huge difference. I am now able to take single subs for as long as I want (in theory). The longest subs I have taken to date are the 45 minute OIII subs in my recent IC 410 image. I took 10 subs and they were all keepers. I'm sure I could do 60 minute (or even longer) subs and still have nice tight and rounds stars. EQMOD and Cartes du Ciel has also been a great addition compared to NexRemote.

The carbon fiber Levenhuk 8" RC will remain to be my long focal length scope for 2015. I am really enjoying the new Teleskop Service carbon fiber 107mm f/6.5 triplet and see it becoming my primary scope. The SV60EDS was sent back to Stellarvue and I should be receiving my new widefield scope on Monday, the William Optics 5-element Star71. I have recently installed the Rigel Systems nStep motor to the focuser on the 107mm scope and am looking forward to automating the focus on this scope. I think this will be another huge upgrade that I will likely want to have on my other two imaging scopes. I am thinking this will be the subject for my January post here at Little Piney Observatory.

I always find it interesting to look back at some of my older images and seeing how I have improved. It so happens I am working on IC 410 this December and I also imaged it last December with my old equipment. Here is a comparison of the shots. Dec 2013 was done with the DSLR camera and was 47 subs of 300 seconds for a total of 3.9 hrs. The Dec 2014 is (so far) a total of 20.5 hours with 18 X 1800 second H-alpha subs, 10 X 2700 second OIII, and 14 X 300 seconds each for RGB. I'm hoping to add some SII soon to finish it up and complete my first Hubble Palette image.

Click on image for better resolution
Update: I finished the Tadpoles up with a total of 28 hours of data. It is complete with h-alpha, OIII, SII, and RGB.



Its also amazing to me how many good people I have come to know in this hobby. I have several new web friends that I hope to meet in person some day. From my good friends Martin Hrdlicka up near Chicago, to Dennis St Germain down in Florida, all the good friends from the old Hayneedle Starparty forum, to all the great people on Cloudynights. It really is a great hobby with great people that help each other learn and get better. I hope you all had a great 2014 and wish nothing but the best for 2015. Have a great new year everyone! :)

Friday, November 28, 2014

New Arrivals at LPO

There has been a changing of the guard recently, on a couple fronts, at Little Piney Observatory.
Those of you that have been following my progress know that the 800mm focal length AT8IN was sold some time ago, and I have since been saving up and looking for a nice apo to replace it. I liked the field of view I got with that scope using the DSLR. The STF-8300M has a smaller chip than the DSLR, so I was looking for a triplet in the 600-700mm focal length range that would produce a similar FOV.
After much research, I decided to purchase the TS Photoline 107mm f/6.5 Super-Apo with 3" CNC focuser and modular carbon fiber tube, from Teleskop Service in Germany. APM offers this exact scope in a metal tube version.
The optics in the scope are said to be very close to the famous LZOS. It is an air-spaced triplet with an FPL-53 element. The interior of the scope and dew shield is lined with a black felt and seems to provide very high contrast views and images.
The first night out with it was a quick eye test to check collimation and do some observing. As expected, the color correction was excellent and viewing with an Explore Scientific 82 degree 8.8mm eyepiece provided extremely high contrast views even when pointed towards a rather large and bright Moon. It can best be described as the often stated, "shimmering diamonds on a black velvet background." I am very impressed with the views this scope provides, and look forward to pushing the magnification for some planetary observing soon.
The scope did not arrive without some anxious moments. The big box it came in was leaking shipping peanuts as I carried it into the house. It was obviously not treated very well by UPS.
Fortunately, it was packed very well and had a smaller box with a nice case inside that protected the scope.
Now the worst part of the whole ordeal. I pulled the scope out of the case and removed the dust cap. When I pulled out the dew shield I saw something that horrified me. I immediately thought that these two screws had been bouncing off the lens during its travel across the Atlantic!! Thankfully, when the dew shield is closed it seals off everything from the optics.
These are two of the three screws that hold the lens cell to the optical tube. Not really something you want to see when you pull out a dew shield. I removed the dew shield and put the screws back on. After getting all three screws snugged up fairly tight everything seemed to be fine.
It was a while before the clouds allowed me to get in some imaging with the scope, but the first night out with it gave me the results I was looking for. The only thing is the carbon fiber tube does not behave like my carbon fiber RC, in that it does not keep its focus as well when the temps drop off at night. I suspect this is because the tube has two 60mm long extensions that have metal threads. These threads will expand in the heat and contract in the cold which changes focus. My FWHM (Full Width Half Maximum) started out in the low 4's and as each frame clicked off the stars grew to a FWHM in the mid 7's after eight 20 min subs. I refocused and frames 9-13 remained in the 4.01 to 4.28 range. Last night I captured some RGB of IC 405, the Flaming Star nebula, and the FWHM was as low as 3.80 and was never higher than 4.61 for the entire night. Since the 3" focuser appears to be pretty stout, I think I will keep it and remedy this problem by getting a Rigel nStep stepper motor with temp sensor and automate my focusing for this scope.
Here's what I managed with the camera the first night out with it. This includes all thirteen of the 20 minute hydrogen alpha subs. Soon I will be getting some new H-alpha data and will get rid of frames 3-8 which should make for a better looking image. I'll be adding RGB and possibly some OIII soon.

Update: I added some RGB to my Ha data on this one.



The other new addition is the Stellarvue SV60EDS. I decided to sell my trusty Levenhuk 80mm f/6 and try out this very small 60mm f/5.5 scope. The 330mm focal length gives me a much wider FOV compared to the 480mm focal length of the 80mm scope. TS even makes a 0.79X reducer/flattener that would work for me and reduce the focal length to 260mm and focal ratio to f/4.3 for an ultra wide fov.
I have yet to find the sweet spot for this scope using the TSFlat2 field flattener. I am not at all happy with my corners, but the color correction seems good and I love the field of view. This is a test shot of the Rosette nebula, two 30 minute subs with no darks, no flats, and no bias frames.
Hopefully I can get the spacing figured out for this scope and get some nice widefield shots. If I cant get the spacing right for the TSFlat2, I might purchase the TS 4-element 0.79X reducer/flattener. This corrector says the spacing needs to be 70mm for up to 350mm focal length. It should be very close with the 330mm fl Stellarvue.
I'm looking forward to using these two scopes a lot more in the near future. Hopefully the weather here will allow this. Although I'm not completely sold yet on the SV60, I plan on keeping the TS 107mm for years to come.
Happy Holidays!

Friday, October 31, 2014

Starizona Pier Adapter and Baader Helical Focuser

With the sale of my CGEM DX mount, I needed to find a new pier adapter for my new Atlas Pro mount. I had been using the adapter from the top of my CGEM DX tripod.

Starizona offers a pier adapter called the CGEM Pier Adapter kit. Since my Atlas Pro worked just fine with my CGEM tripod adapter, I knew this would work fine with the Atlas. It likely will also work on a few other mounts as well, but I'm not able to verify this.




So far this seems to be working out great for mounting the Atlas Pro to the pier. I may be putting a little thicker top plate on, that the pier adapter is sitting on, but its working fine as it is so I'm in no big hurry to do that.

The other upgrade I've been wanting to do for a while is find a solution for focusing my guide camera on the Starlight Xpress OAG. It uses a thumbscrew and an allen set screw. You loosen these and slide the camera up and down the stalk to focus the camera and then lock these two down. It doesnt slide very smoothly and its quite difficult to get the camera focused.

The OAG uses a male C-mount and I ended up getting this c-mount to t-thread adapter from ScopeStuff and the Baader helical focuser from Adorama. Agena Astro was out of stock on this item at the time but I was able to find one at Adorama for the same price. Both places are a pleasure to do business with.

This worked out great and makes focusing the QHY5L-II guide camera much easier. The focuser has an internal compression ring and three thumbscrews for clamping the camera in place and also includes a focus lock screw.




I'm enjoying the new upgrades as small as they may seem. Anything that makes this hobby a little easier gets a big thumbs up from me! I'm looking forward to the coming weeks here at Little Piney Observatory. I have some bigger plans in the works so stay tuned. :)


Thursday, September 25, 2014

EQASCOM Polar Scope Tool



This is really just an update from my post a few days ago about the Atlas Pro AZ/EQ-G mount and the new software we've been trying out to get everything up and running. I did not mention Alignmaster because we simply could not get it to work correctly. I'm still not sure if this is because of user error or not but we have found something else that seems to work great.

This method does require that you have a view of Polaris (for Northern Hemisphere users). When using a polar scope it is very important to place the RA axis of the mount precisely where Cassiopeia and/or the Big Dipper appears in the sky. This can be really difficult to judge sometimes and usually it is just a guess. EQASCOM and Chris Shillito of the EQMOD Project has come up with a simple solution.

I wont go through the routine here, but will say it is very easy and it just works. After going through this simple procedure the guiding graph in PHD2 looked much improved compared to just eyeballing it. It seems to be very precise. Here's a screenshot of the graph after aligning the mount with this method.


Here's another after making a few small adjustments. The mount only required that very small corrections be issued from PHD2.


These were done with the 80mm f/6 apo, the next night out we tried guiding the 8RC at 1600mm focal length and it performed great. Looking forward to getting my camera back from SBIG and putting it all to work.

For complete details on using this method please see Chris' video.


Detailed written instructions can be found here:

http://eq-mod.sourceforge.net/docs/PolarScopeAlignment.pdf


Monday, September 22, 2014

Atlas Pro AZ/EQ-G

I managed to get several images with the CGEM DX mount over the last 2 1/2 years. Some pretty good, some not so good. It was just very unpredictable, and I started saving up some money and sold the AT8IN telescope to help fund a new mount.

There were several that I had my eye on. The new iOptron CEM60 EC seemed to be a very nice mount. The Losmandy G11 has been trusted for years and has recently been refined with the release of the Gemini 2 hand controller. Both of these mounts will carry a maximum payload of 60 lbs and looked appealing. The new Orion HDX110, which is the Skywatcher EQ8 with the Orion name, also looked very nice with its capabilities of handling up to 110 lbs of weight.

There are a few things I'd still like to buy for my astrophotography hobby. I still need to get the Astrodon OIII and SII narrowband filters. I would also like to automate my focusing with motorized Moonlite focusers on my telescopes. And I would like a nice 110-130mm apo triplet to have for visual use, as well as fill the void in my imaging line of scopes left from selling the AT8IN. Its a pretty big jump from the 480mm focal length of the 80mm triplet up to the RC's 1150mm focal length using the CCDT67 Telecompressor. So I'd really like something in the 700-800mm range.

After weighing my mount options with my wants/needs, I decided to settle for a smaller mount. The new Atlas Pro shares a few features of its big brother, the HDX110. They both use the same Altitude adjuster that is much smoother than most mounts on the market. They both use belt driven stepper motors with dual encoders. And they both use closed-loop electronics which allows you to manually move the scope, or rebalance, without it loosing its alignment. The Atlas Pro AZ/EQ-G it would be!

I ordered the new mount from Orion and it arrived in two boxes about a week later. When I set up my pier last year I removed the mount adapter from the top of my CGEM DX tripod and fabricated a way to fasten it to my pier plate. I was hoping it would work with my new mount. The metal post for adjusting azimuth was too long for the Atlas Pro mount, but it was as simple as removing the CGEM DX post and screwing in the one that came on my Atlas Pro tripod. It fits!


This picture shows the mount set up for my 80mm triplet. For larger scopes, the mount also comes with a counterweight bar extension and another 11 lb counterweight.


 The mount is so quiet when slewing! I just had to remove the cover to check out the stepper motors and drive belts. This is a really nice system and much better than gear-to-gear in my opinion. In addition to being quieter the backlash is also significantly reduced or eliminated. There is always some backlash in any gear-to-gear system.


This is a close up of the "Captain's Wheel" DEC clutch. The small t-bolt under it allows the counterweight shaft to retract up inside of the mount for easy transporting and storing.


Here is the RA clutch and just below it is the illuminated polar scope. The brightness of the illuminated scope can be adjusted with the hand controller.


This is the adjustment for altitude with the handle retracted. It is much smoother than the other equatorial mounts I have used. Below it is shown with handle out ready for adjustment.


I have not been able to really use the scope yet for imaging, but I am confident that this will be an excellent mount for astrophotography. The very first night, we did a rough polar alignment using the polar scope and did a little autoguiding and it performed great. Here is the PHD graph with no adjustment of the PHD2 settings and the rough polar alignment. I am sure with a more refined polar alignment and some fine tuning in PHD this will get even better.


One big reason I wanted to go with this mount is that it is supported by the EQMOD Project. I have read great things about EQMOD and EQASCOM and wanted this program for controlling the mount/telescope. It really is a well thought out program with excellent capabilities. I am still trying to learn more about it but everything so far has been positive. I will report in more detail about EQASCOM as soon as I feel comfortable using it and learn more about it. Please check into it yourself to see if your mount is supported. If so, I think you will really like the program. I did purchase the recommended interface cable from Shoestring Astronomy for connecting the mount to the computer. For the Atlas Pro AZ/EQ-G this cable is the USB2EQ5. For regular Atlas owners this would be the USB2EQ6 interface cable.


For aligning the mount for goto you can make a pointing model using several stars. Usually just a star to the west and one to the east will be good enough for casual goto performance. This is great for observing but with Elbrus plate-solving software its not really needed at all for imaging.


I should also mention another piece of software that is very important. With the interface cable from Shoestring Astronomy, you no longer use the hand controller. EQASCOM controls your mount but you'll need something else if you want goto capabilities. Stellarium is great for this but I found that it was too much of a memory hog for my old desktop that I have in the observatory. I found a free program that others are using called Cartes du Ciel. So far it has worked great and seems to be a nice program.



Just select a point on the sky chart to get coordinates for your plate solving software or select slew for goto. With tracking enabled it will track where your scope is pointing on the sky chart.

By this time next month I hope to have a few images under my belt using the new set up. Hopefully by then I can report a lot more on the new software and the performance of the new mount. I believe that the Atlas Pro AZ/EQ-G will be a wonderful addition at Little Piney Observatory. Clear skies everyone!

Sunday, August 17, 2014

Improving Corners and Homemade Dew Shields

This months post is a follow up to last months review of the Starlight Xpress off-axis guider. Adding the OAG in the imaging train needed some recalculating of the spacing for the Astro Physics CCDT67 Telecompressor that I use with my RC telescope. Most all scopes require some sort of corrector to make the stars in the corners of the image round. I noticed I had some serious problems but I had also experienced problems with my focuser and had blamed the aberrations in the corners on slop in the focuser. I took the focuser apart and found the problem and fixed it. I expected things to be well again but that was not the case at all.

PixInsight has a really neat tool under 'Script' in 'Image Analysis' called Aberration Inspector. It divides the image up into sections and will show in good detail how your stars look throughout the image. Here's what aberration inspector showed on my recent Bubble Nebula image.


The lower corners show extreme curvature issues and the top is so bad that the stars appear to be badly out of focus. Things are nice and tight in the center. Since the focuser was now fixed it was time to look elsewhere. I decided to careful measure my backspacing again and found that it was less than what it was previously before I added the OAG.

I mentioned in last months post that I went from M42 adapters to M48. Agena Astro has a limited selection of these spacers and I had the shortest one already with the 1/4" (6.4mm) spacer. The next step up is a 1/2" spacer. I really didnt think that I needed that much more, but at just $16.95 I decided to give it a try. It seems that this has again put things in the sweet spot for the Telecompressor. I decided to test it on a large Open Cluster and chose the Double Cluster in the constellation Cassiopeia. Here's what PixInsight's Aberration Inspector showed after increasing the spacing.



The stars in the corners are clearly much better than before. I still have work to do however as I ran across some more issues. The prism of the OAG was too far into the light path and is causing some weird diffraction patterns on the stars to the right side. I think this should be easily fixed though by simply raising the prism up a little more.

With the issue of the corner stars fixed I decided to tackle another problem I have had for a while. Dew is a huge problem here in Arkansas and a while back I had invested in a secondary dew heater for the RC scope. The problem of dew was fixed but I have not been happy with the shapes of my stars since adding the heater. The secondary dew heater was just slightly larger than the secondary holder on my 8" RC leaving the edges of the heater adding to the secondary obstruction. The edges of the heater are not particularly smooth and this, combined with the wires ran across the spider vanes left a mess of the diffraction around my stars. I put up with it as long as I could and finally peeled the heater off and looked for other solutions.

Typical Diffraction pattern with secondary dew heater

I have made a few of my own dew shields. In fact, I have never bought a dew shield before. I think I found this on the website for the DewBuster heater controllers and I must say that they work great. I went to the local Lowes hardware store and bought a roll of Reflectix insulation, a can of 3M Super 77 multipurpose adhesive, a box of the heavy duty velcro, and a can of flat black spray paint. Using these items it is quick and simple way to make a homemade dew shield.

Reflectix Insulation
Start by wrapping the Reflectix around the OTA and cut it at the desired width. Next, just notch around any dovetails you might have. For my RC, I have an ADM Losmandy style on the bottom and a Vixen style on top. Making your own dew shield likely makes for a much better fit if you have custom accessories added. The Reflectix is shiny on both sides and the inside of the shield needs to be painted flat black. After the shield has been test fit and cut as desired, the inside of the shield needs to be sprayed with the 3M glue. This acts as a primer and allows the paint to stick. Without this step the paint will not stick to the Reflectix material.




After the 3M adhesive has dried you can then spray the flat black paint. Once it has dried you can apply the velcro in the desired locations and you are finished. Presto! A dew shield! I added the soft part of the velcro along the back of the shield to protect the finish of the scope.


I also had a heater strip for my C8 telescope and decided to also add it just past the halfway point towards the back end of the OTA. I wasnt sure how this would work with my scope having a carbon fiber tube but after two nights out the mirrors have remained clear of dew. The dew shield has been soaking wet on both nights but the scope has been dry both inside and out!

I will say that I believe the secondary dew heater that I have will work fine on the 10" and larger scopes. The heater is just a little bit too big for the 8" RC's. Where the wires come out of the heater you simply can not turn them sharp enough to keep them out of the light path, so this was another source of diffraction issues.



The diffraction pattern around the stars is much improved without the secondary dew heater. Though this shows other issues with the tracking/guiding, diffraction is no longer a mess. Just last night my wife and I started trying out ASCOM pulse guiding and it seems to be doing a better job than guiding through the ST-4 port on the mount. Maybe this will be a future post from Little Piney Observatory. One thing I have learned since I started imaging, is there is always something new to learn in this hobby!

Clear Skies!