Tag Archives: adelaide

Milky Way

Every amateur astronomer knows that the clouds will roll in as the delivery man’s van leaves your front door.  This happened to me again these last two weeks.

I treated myself to a new ZWO ASI224MC camera with a Canon lens adapter, all purchased online from Bintel. Very small and compact and it is intended to help me with my polar alignment, guiding and some planetary imaging. It’s main advantage is its very low read noise which means that you can take many short images and add the individual image frames in post processing to form a longer duration image without adding significant noise in the process. I’m not planning any huge expansion into planetary astrophotography but it would be nice to have something to do when the moon is up and I cannot do long exposure, deep sky stuff.

ZWO-New-ASI120MC-Camera-

ZWO T2 to EOS Adapter

Last night was clear with the Moon and Jupiter right overhead and I started everything up; EQ6-R mount with the ZWO ASI224MC camera on a Canon 60mm EFS lens. For the software I used Sharpcap Pro, it will cost you 10 pounds annually to get the Pro version that lets you do polar alignment. This works very well and will work with any camera that is recognized by Sharpcap. Also read one of my previous posts about SparkoCam.

Sharpcap Polar Alignment

You just follow instructions and move the mount az and alt adjustments to get the polar axis of the mount perfectly on the celestial pole. No guessing or frustration and a perfect result. That’s worth more than 10 pounds!

My first attempts at using the ASI224MC camera with an Orion EON 80ED on the moon and Jupiter was not great, I have a lot of learning to do and I did not spend a lot of time trying. Just a quick picture of the moon…

Moon ASI224MC ED80

I then took a number of images of the Milky Way with my modified Canon 600D with a Canon 60mm EFS lens directly on the mount and took a series of 60 images of (quite short) 30 seconds exposures at f3.2 and 400ASA as well as a number of dark frames of whatever was directly overhead at the time. It happened to be the center of our galaxy. As usual, combined with Deep Sky Stacker and processed with LR4. I was sitting inside on the sofa nice and warm, watching a movie while Magic Lantern was managing the camera outside in the cold. Did I mention that it was cold?

Picture saved with settings applied.

 

“First Light” for EQ6-R

I used the new laser alignment tool last night and it took me about 2 minutes to achieve polar alignment for the EQ6-R. I then used a 1-star alignment to get the mount setup.

To test, I used my trusty Canon 600D (modified) with a Sigma APO 120-400mm at 400mm and f/5.6 for a single 3 minute exposure. This is not a lens that I would normally use for astrophotography but I wanted a long focal length to test the alignment and tracking.

Well, let’s say that I was not disappointed with the result.The following image of the Carina Nebula is an unguided 3 minutes exposure at 400mm and there is not a trace of star trials, even when zoomed in. Take a look….

Carina Nebula - Test Image

Carina Nebula – Test Image

De-Forking a Meade 8″ SCT OTA

This sound a bit obscene but I promise that no animals, people or telescopes were harmed in the process.

The Meade SCT in question is an 8″  2080 model that I purchased around 1992. I used it quite a bit for a number of years until my interest turned to astrophotography. The specific model do not have a dec motor and the RA motor is running off 240VAC.

img_2775Over time I build an invertor that could work from AC or 12VDC and allowed me to vary the frequency  around the nominal 50Hz and I could therefore do some manual guiding in RA with a set of buttons and with the existing fine controls on the DEC. It worked a treat for a while but anybody that has guided long exposures manually will know that its a very tedious exercise with unpredictable results.

Well, now everything has changed. The new Skywatcher EQ6-R can easily carry the 8″ OTA (Optical Tube Assembly) as well as my ED 80mm and new opportunities becomes available.

I had to de-fork the OTA out of the Meade fork mount to allow me to fit a Losmandy plate to allow for the OTA to be fitted to the EQ6-R. There are a lot of guidance on the web for how to do this but I used the following site:

http://uncle-rods.blogspot.com.au/search?q=getting+deforked

Its remarkable easy and took no time at all.

Loosen two bolts on one of the arms first.

img_2778

Then remove three small bolts from each side of the tube. Take care to work on a soft surface and have someone assist you to make sure you don’t scratch the tube surface.img_2779

And its off!img_2780

Now to mount the Losmandy DM8 kit into the existing holes on the OTA.img_2783

10 minutes later…img_2784 img_2785 img_2786

And now the amazing Meade 8″ OTA can be used on a very capable and accurate mount. A big change for me and there should be some new images soon.

img_2788With my luck it will probably be cloudy and rainy for a month now ….

Unpacking the SkyWatcher EQ6-R mount

The EQ6-R has arrived on Thursday and I unpacked it that night. No surprises there….

Here are some photos of the process:

img_2751 img_2753 img_2754 img_2755img_2756 img_2757 img_2758The handle makes it easy to lift the mount head with one hand.img_2759 img_2762The adjustments bolts look quite solid, at least 15mm on the main altitude bolt and 12mm on the other three.img_2766 img_2767Saddle takes Vixen and Losmandy.img_2768 Probably not many changes visible here on the cable panel except for the power connector that is now a solid screw on type.img_2769 img_2770Synscan loaded with version 04.37.03.

img_2772 img_2773 img_2774Waiting for the weekend now and a mounting plate for my Orion ED 80mm EON and also a Losmandy DM8  dovetail plate for my Meade 8″ SCT.

SkyWatcher EQ6-R mount

Well, I have finally surrendered to the temptation of getting myself a heavy mount.

Initially I was looking at the Skywatcher NEQ6 Pro but then discovered that the brand new Skywatcher EQ6-R mount is available on a limited product release from an Aussie supplier. Major changes are the belt driven system with zero backlash, PPEC support, newer motor drive with lower periodic error, improved tracking accuracy, 20kg payload capacity and a carrying handle!

skywatcher_eq6r

Basic specs are as follows:

eq6-r-specs

Will be delivered next week so expect more feedback here soon ……

Carina Nebula from under a streetlamp

I had to test my new tracker with autoguiding and could not get away to a dark site so I decided to test it in the front garden where I could reach further south towards Carina Nebula. Unfortunately I have a bright streetlamp in front of my house. I tried to shield the light from falling on the camera and lens to avoid the worst effects of the light conditions. I use a modified Canon 350D and got 29 light frames of 30 seconds each, 7 dark frames and 18 bias frames at f/5.6, ISO 800 with a 250mm focal length.  Ideally you would try to get longer exposures than 30 seconds but the sky was so bright that I had to limit the exposure time for each frame.

Picture saved with settings applied.

Testing the new tracker mount with autoguider

I finished the construction of the new tracker to the point where I could test it under a suburban night sky.

New Tracker-8990 New Tracker-8988

I mounted a piece of angle iron onto the RA shaft and mounted two camera ball heads on it; one for the imaging DSLR and one for the webcam autoguider.

New Tracker-8991  New Tracker-8994

To align the mount I use a green laser pointer that is mounted on a bracket that sits directly on the RA shaft. This allows me to to align the mount very accurately to the SCP. I was very pleasantly surprised with the stability of this new mount. There is almost no vibration or oscillations in the mount, even when touching the mount or adjusting the settings on the camera. It is reasonably heavy but it will also be able to carry quite a payload. At this stage I have only tested it with a DSLR but the next step will be to load it up with an Orion ED 80mm to see how it performs. Maybe it will take a 8″ SCT optical tube as well …..

Due to the very light suburban conditions I only took a few photos to see how the tracking and autoguiding work on the new mount.

New Tracker-9001 Wide field view of the Southern Cross overhead taken with Canon 600D with a Tokina lens at 16mm and a single 4 minute exposure at f/3.5 and ISO-100.

New Tracker-9046 The same Canon DSLR with a Canon 60mm lens and a single 90 second exposure at f/3.2 and ISO-400.

New Tracker-9005  The same Canon DSLR with a Canon EFS 55-250mm lens at 250mm and a single 2 minute exposure at f/5.6 and ISO-400. This is the Omega Centauri globular cluster.

I am happy with the performance of the mount. The stars are mostly round. The stepper motor has a nice quiet hum and the worm and worm gear seems to hit it off quite well without binding.  It all works quite smoothly. I must also mention that the autoguiding software from Stark Labs; PHD Guiding (http://www.stark-labs.com/phdguiding.html) works beautifully and I could focus on the imaging and let the software and webcam look after the tracking.

New Tracker-8982

I guess the next step is to take this new setup out to a dark spot under a clear sky and see what it can do. I can’t wait!

Building a new Astrophotography Tracker Mount

If you have been reading my blog you will know that I love building things. I almost like it more than using things. So, after my recent experiment with a tracking mount I decided to start again, from scratch, to try and make a more robust, heavy weight mount that will not complain when I load it up with cameras and scopes. I also use the iOptron SkyTracker a lot but you cannot load it up too much.

The previous tracking mount is shown in one of my previous posts, Look at https://starsinphotos.wordpress.com/2014/09/23/diy-autoguider-for-long-exposure-astrophotography-part-2/ . This mounts works surprisingly well but it looks like a dogs breakfast, it’s sensitive to bumps and it is too bulky to transport easily.

My new design will be more solid with a steel based design rather than aluminium. Its harder to machine but the design is relatively simple so it is quite easy to make. I have decided on a few design parameters that will make the design robust and will not require any skilled machining capability (apart from the worm wheel and gear). I will also make a new worm gear combination (130mm diameter with approximately 270 teeth. The previous one I made was not very accurate and it only tracked smoothly for about 3 hours at a time, then I had to “rewind” the RA axis to get to the start of the good section on the work gear. My stepper controller design have buttons for a fast forward and rewind on the RA drive.

The new tracker design is based on a square section of 125mm mild steel U-channel with two pillow block bearings that holds the 20mm steel RA shaft.

s-8604 s-8606

It should be possible to get the steel supplier to cut the U-channel to the correct length when you buy it but I got an offcut cheap and had to spend a few hours to get it nice and square. The U channel and the 20mm rod cost me $10. The two pillow block bearings was a bit more expensive, the two of them cost about $60.

So now I have the RA shaft mounted and it feels VERY solid. I am thinking that I might be able to load my 8″ SCT OTA on to the mount if all goes well. The new 140mm worm gear will fit onto the 20mm shaft on the left (or bottom) side and the camera / scope mount will be on the right (top) side. The stepper motor and worm will be below the U-channel on the bottom.

I am going to try and build the tracker without any ability to adjust for altitude polar alignment. In my opinion, its too hard to get a very solid mount if you add the adjustment elements to the design. This mount will be mounted on a fixed altitude block that is centred on Adelaide (35 degrees south). I will use the Meade tripod legs to make large changes to that and small changes will be made by an adjustable tripod foot consisting of an adjustable pipe flange that can be rotated to make small adjustments on the tripod leg facing south. Azimuth will be adjustable with the Meade tripod head bolt. I may go so far as to include a method for making small adjustments to the azimuth as I have battled with that in the past.

For accurate polar aligment I will keep on using my green laser pointer on a small aluminium bracket that attaches to the RA shaft itself. This implies that I can achieve very good polar alignment with a mount that may not be perfectly square and with bearings that are not fitted very accurately on the mount. It’s legal to use a green laser pointer in South Australia if you have the correct documentation with you.

My existing stepper controller and autoguider works well and I will use it again for this mount.

Update 22 January 2015:

I have now got two new 130mm diameter aluminium “blanks” for the new worm gear. This time I had them professionally machined so that they will be 100% square on the 20mm shaft, unlike last time…..

2 x 130mm Al disks

New tracker components 1

Over the next few days I will cut the worm gear and a new worm. I will post some photos when it is done.

Update 27 January 2015:

Yesterday, I cut the worm gear and it turned out much better than before. I have 279 teeth on this disk and hopefully they will be quite smooth after I have polished them.

Worm gear Jan15-1

Worm detail Jan15-1

The new tracker is slowly coming together now…

Tracker progress Jan15-1

Now for the worm….

I will update this post as the mount gets built over the next few weeks.

Comments and questions are welcome…

Total Lunar Eclipse – 8 October 2014

A total lunar eclipse occured on 8 October 2014 and I had it all visible from my front door. I did not plan on photographing the event but decided at the last moment that I had to give it a try as it was available from my garden. I used an Orion EON 80mm ED Apochromatic Refractor with a focal length of 500mm on a fixed tripod with a Canon 600D. In hindsight it would have been much better to use my tracker to keep the moon in the centre of the frame and to prevent blurring due to the moon’s movement in the longer exposures during totality. Oh well, live and learn.

Lunar Eclipse Series M Lunar Eclipse-6361 Lunar Eclipse-6367 Lunar Eclipse-6376 Lunar Eclipse-6389 Lunar Eclipse-6398 Lunar Eclipse-6405 Lunar Eclipse-6408 Lunar Eclipse-6430 Lunar Eclipse-6451 Lunar Eclipse-6460 Lunar Eclipse-6474 Lunar Eclipse-6507 Lunar Eclipse-6516 Lunar Eclipse-6518 Lunar Eclipse-6551 Lunar Eclipse-6556 Lunar Eclipse-6560 Lunar Eclipse-6566 Lunar Eclipse-6571 Lunar Eclipse-6581