Tŷ Du Observatory

Happy New Year

A new year and a new start for me. I’ve bought a QHY-5 guide camera and some scope rings to have a go at autoguiding. I had several viewing sessions towards the end of last year, but haven’t updated the site as most of the images are duplicates of those I’ve taken before. Now that I can improve my images I will consider rebuilding this site to make it easier for me to update.

I’m looking forward to being able to start imaging fainter objects and also to tease more detail out of those I have imaged in the past now that I can do longer exposures.

Initial tests look promising but I’ve had to overcome a number of issues, such as the guide software crashing every 5 minutes and the weather not cooperating! Last night was my first chance to get everything working but it didn’t clear until after 10pm so I didn’t get to bed until after 3am but I did leave the scope tracking so as not to miss this rare opportunity to image with a clear sky.

Here are a couple of images from last night:

The Horsehead Nebula in Orion	M1 – The Crab Nebula	NGC457 – The Owl Cluster
NGC891 – Edge on Galaxy	NGC2403 2×5 minutes	NGC2403 6×1 minute
NGC2841 – 100×2 minutes

Guided using Guidemaster 2 (beta) 70mm refracter and QHY-5 guide camera. Guide signals from camera to mount, not ASCOM.

Images with 254mm Skywatcher relector on EQ6 Pro Mount with Atik 16ic mono camera.

NGC457 the Owl Cluster was one of the first objects I imaged, so I thought it fitting that I was able to include this amongst my first autoguided images.

Another clear night, and it looks like there’ll be a few more over the weekend.

I spent some time playing with PemPro and PERecorder to see if I could make a PEC curve for the mount. It looks like each worm cycle has a different profile so I’m not sure how much help it would be. After spending several hours using the webcam to record PE I decided enough was enough and moved on to imaging with the Atik 16ic.

I didn’t get much, it was already late so really it was just a test of the PEC experiment.

M15 – Globular Cluster

M27 – The Dumbbell Nebula

M57 – The Ring Nebula

Even after applying PEC I was still unable to manage more than about 30 seconds per frame.

I wasn’t expecting a gap in the clouds but I made the most of the opportunity when it came. I only wish I’d been able to stay awake longer to take advantage of this rare occurrence.

As I noticed the clouds breaking up I decided to do some mount tuning before starting an imaging session. I’ve had a couple of attempts since the last post, but haven’t been happy with the amount of movement in the images.

I started by realigning my polar scope. I did this during daylight by sighting on my neighbours weather vane and rotating the mount to make sure the cross hairs stay centered. Some adjustment was required but it only took a few minutes to rectify the issue.

Next I found I could detect movement in the mount head by rocking it with my hand. I made some adjustments to the hex bolts and was able to remove all movement, but knew this could have an affect on the gear mesh so my next step was to power it up and slew the scope around. Sure enough the mesh was too tight and I had to make some minor adjustments to make sure the gears moved without jamming and there was no movement when I rocked the mount head.

What else could be affecting my imaging? Well I’ve always been a little concerned about the third weight I use to balance the scope. I described in an earlier post how I picked up a 5KG weight-lifting weight from a local supermarket to help balance the scope and sandwiched this between the 2 weights that came with the mount. The central hole in the weight is too big for the shaft but until now I hadn’t taken any notice of this. To remedy this issue I took a roll of masking tape and wound it around the shaft until the weight fitted snuggly over – problem solved.

So now I only had to wait for darkness to see if I’d made things worse or better.

Turning on “Messier labels” in Starry night showed me a number of the southern M’s were within reach being higher in the sky during the summer months. Some of these I’ve never imaged before so I set about what turned into a miny Messier marathon. Initially I was limited to 10 second images as the sky was not yet fully dark and longer exposures where not possible. I started with the lowest M I could get at given the obstacles that hinder my South and South West view. So the session went something like M28,M22, M8, M21, M23, M9, M18, M17 and M16.

M8 was disappointing, I found I was still getting movement in the images so longer exposures were not possible. For this reason I skipped M20 the Triffid stayed mostly with Clusters.

I finished the evening by looking at PemPro and PERecorder to see if I could create a PEC curve to help with the mount movement, but time ran out and at 1:20am I called it a day. Next time I get a clear night I’ll start recording PE earlier to make sure I have enough time to do this properly. What I did find was it looks like the mount has +20 to -20 Arcsecond movement which seems to be about normal for an EQ6. I think need at least half this for decent images.

So here are the new images, I’ll have to remember to update the Messier Catalogue on the images page.

M9 – Globular Cluster	M16 – The Eagle Nebula	M17 – The Swan Nebula
M18 – The Black Swan	M21 – Open Cluster	M22 – Saggittarius Cluster
M23 – Open Cluster	M28 – Globular Cluster

Finally I got out with the new camera last night, it wasn’t the clearest of nights and by 1am there was complete cloud cover, but I managed a couple of hundred frames (FITS) which I now have to process.

The reason I have FITS and not an AVI is that K3CCDTools failed to work. I’d configured the software a few days ago and run some darkframe tests just to make sure everything was ok, but on the night it let me down. The menu let me select Atik and the camera was on the list but when I selected it the Atik control panel failed to open and the control panel icon was greyed out. I’ll have to look into this but it gave me a chance to look at ArtemisCapture which comes with the camera.

The first thing I noticed was that focusing took longer than usual, this was mainly because I’d left “auto-stretch” on which meant the image was very dark. Later I found the focus tool but I think I did an “OK” job without it.

So here it is, the image that I’ve waited a month to see, first-light with the Atik 16ic. I was aiming North West after aligning on Deneb and after slewing star to star northwards I came across M52. The image is a stack of 9 from 12×10second exposures, stacked in DeepSkyStacker and processed in PhotoShop.

I have an image of M52 taken with the SPC900NC for comparison but after putting the images together they are different orientations so while it’s difficult to demonstrate here it does give me a chance to show the difference in fields of view between the two cameras.

After taking 12 frames of M52 I moved around the sky for the next 5 hours, taking a few frames here and there just to see what I could see. What I hadn’t seen was the cloud coming over and it wasn’t until I went out to put the scope away that I realized there wasn’t a star to be seen with the unaided eye.

I couldn’t resist taking a few frames of the owl cluster (NGC457) in Cassiopeiae which I’ve also taken with the 1004x and SPC900, but I think this is my best yet.

Here’s another from the same session, my best M1 so far. When you consider this was late in the session and almost certainly taken  through cloud it’s not that bad. Well at least it’s recognisable.

I haven’t had a chance to take my new Atik16ic out for a test run yet, but I did try a dark frame and I’m a little concerned. Is it normal to see a darkframe like this?

This was 20 seconds with the lens cover on. I was hoping for a completely black image and was very surprised to find this light area across the image. I ran several test frames using  ArtemisCapture and this image was one of the last when the camera had been on for several minutes. The image was taken indoors, the room temperature was around 20°C any feedback would be very helpful.