Galaxy

GalaxyGalaxy

Galaxy

Galaxy

Weather report: Brrrrrr!  We’ve had excellent clear skies for the last 3 nights and with the clear skies comes the cold at this time of year.  The observatory has been down to -5°C but we’re in a warm spot here and temperatures on the drive to work have dropped to -9°C! The cold weather from Siberia has been dry which has kept mirrors and lenses mist free and no wind has added to the perfect viewing conditions.

My only complaint is the moon has been very bright which with frames up to 20 minutes each has caused a lot of over-exposure which I’ve had to attempt to process out. Multiple 10 minute exposures have been the norm with few spoiled frames due to the lack of wind.

Aiming away from the moon has limited my targets and concentrated mostly around the Ursa Major area.

One of my favourite Galaxies sits in this area – M81.  M81 and it’s close neighbour Galaxy M82 made good targets for the CDD 16ic and the Philips webcam but I’ve struggled to get clear consistent images with the Canon.  Here’s my latest effort:

M81 16 x 12minutes iso800

M82 cropped from the same frames is here:

M82 16 x 12minutes iso800

Spiral Galaxy M101 with the recent Super Nova SN-2011fe made an interesting smudge on my test frame so I left the camera running through the night taking 10 minute sub-frames.

M101 28 x 10 minutes

I think this is my best M101 so far

M106 is another galaxy that I’ve imaged before and this image is a composite of 8 best frames from a set of 24 again taken through the night.  There’s some faint fuzzies visible and some faint spiral arms outside of the usually imaged inner disk.

M106 8 x 15minutes

M51 is another Galaxy, or double Galaxy, that I’ve imaged many times before.  As with all these galaxies any movement of the camera results in loss of detail in the final image. I’m disappointed with this one although there are positives to be taken from it. All the images are processed with Deep Sky Stacker and the resulting 16 bit TIFF files are processed in GIMP which can only handle 8 bit TIFFs. As a result the images published here are not the same as the originals.

M51 5 x 5 minutes

Taking a break from the galaxies I turned the scope to M44 the Beehive Cluster. I’ve been very impressed with the individual star definition in the images I’ve taken this week and I thought a cluster would give me some raw materials to explore this.  As it turned out I have better examples from other images but I’m happy with the way this turned out.

M44 10 x 2 minutes

Stars:

The bright star in this next image is magnitude 10.3 so I’m guessing the neighbouring star is a little fainter.  I’ve been impressed by the way these stars have remained separate and have noticed on some frames stars overlapping with clear definition between the two.  I’ll have to go back through the frames to find a good example.

Faint Stars

More stars showing an assortment of sizes and magnitudes but all very clearly defined.

Nice and Round

The Baader MPCC has made a fantastic difference to the images with round stars across the whole frame.  My only problem has been getting the camera square to the light path with rugby ball stars resulting.  I’ve changed all the bolts on the focuser in an attempt to square things up and I think I may have fixed it

Failed: I have some frames from the NGC2237/NGC2246 Rosette Nebula area in Monoceros but the unmodified Canon isn’t able to pick up much nebulosity in the area. This is where a large format CCD would really come into its own. Maybe one day, if my numbers come up on the lottery.

Waiting for more clear skies …

 28th January 2012

I spent some time this afternoon modifying the focuser (putting some shims under 1 side) and changing the bolts from the original to longer bolts.  I knew this would mess up the collimation and the focus but I’ve been pulling the camera to one side with tape in an effort to get the light path straight and I though this would be a more permanent solution.

I’m not sure what the correct method is to square the focuser to the tube but I held a straight edge across the opening of the tube and through the centre line of the camera.  Its crude but it appears to have worked with a few washers helping to make everything square (ish).

Looking forward to the clear skies I started early and quickly collimated and focused and even though the bright stars had halos I was ready to capture some long exposures. It’s now just 19:23 and already the clouds are too thick and there is a threat of rain (or snow) so I’ve had to close the roof – doh!  If it clears up later I may have another go but I think that could be the last “session” in January.

With the trees bare I now have good views south and sweeping around through the east to the north east.  The view is blocked at lower levels by houses to the east and next door’s shed to the north but can’t grumble

Given this view and this time of year I’ve been trying to get to grips with CDC (Cartes du Ciel) to locate deep-sky objects that may be of interest.  The obvious and probably favourite of most amateurs M42 the Orion Nebula is currently perfectly positioned in the early evening but crosses the meridian as the night progresses and as this would require some setting up I tend to move on to other objects.

I think I’ll change the format of this blog at some point as I’m starting to take multiple shots of the same objects which could now have pages of their own.

Comparing my efforts with “Google Images” it seems I still have plenty of room for improvement!

I’m not the most patient of people so taking long exposures drives me crazy but over the last few nights I did manage to get 2 x 20 minute guided exposures of M45 (The Pleiades). A misted primary made the images look a little out of focus, I even found frost on the secondary so under those conditions anything was a bonus.  But still 20 mins is a lot of photons so hopefully this bodes well for the future.

Oh yes, VIGNETTING is starting to become an issue.  Is the focus tube extending too far towards the secondary? maybe, maybe I need to get to the bottom of it or find a good way to remove it in the processing.

So over the last few days I’ve taken these shots:

2012-01-12:

M42 The Orion Nebula (10 x 2 minutes)

2012-01-15:

The Horsehead Nebula (4 x 10 minutes) it would benefit from more minutes and narrow-band filters, but it's a start

M42 The Orion Nebula (5 x 5 minutes)

M45 The Pleiades (5 x 10 minutes)

2012-01-16:

SN2011fe is still clearly visible in M101 the Pinwheel Galaxy.

M45 The Pleiades (2 x 20 minutes)

NGC1977 The Running Man Nebula (9 x 3 minutes)

All images taken/processed:

• Skywatcher 250 on EQ6 Pro mount.
• Star-chaser 80 guidescope with Atik 16ic Guide camera
• Canon 300d with Baader MPCC and skyglow filter
•  Software: EQASCOM, PHD Guiding, CDC, Deepsky Stacker, GIMP

It took a good couple of hours after reassembly to collimate it .  Luckily my son was on hand to mark a piece of paper as I turned the LC through 90, 180, 270 degrees and marked where the dot landed.  Adjusting the the grub screws by what appeared to be insignificant amounts had a huge effect on the beam.  I got it to as close as I could – not perfect, but enough to know that over a short distance (like 2.4 meters up and down my OTA) the margin of error shouldn’t be a problem.

Looking at the out-of-focus stars from last nights focusing session I think I took them before the Baader MPCC was aligned (collimate) properly so the image is very misleading.

I need to collimate the scope

Out of focus star with poor collimation

How bad is that? The shape should be an exact circle and the inner black circle should be perfectly central within the bright circle.  3 of the mirror brackets are visible to the left of the image, they should either all (6 on this model) be visible, perfectly symmetrical around the bright circle or they should all be invisible just outside the field of view.

The rain is hammering against the observatory roof again but at least the wind has died down.  I’m not sure if I’ll get another imaging session in this year, but never say never …

I’ve solved the slewing to wrong location issue, I’m not sure how but it did coincide with me reverting to an older version of ASCOM and adopting Cartes du Ciel in preference to the StarCalc.

Since the last imaging session I’ve:

• Switched back to the Canon 300d for imaging with the Atik 16ic for guiding
• Installed dual-speed focuser
• Installed Baader MPCC
• Installed Skyglow filter
• Changed Laptop to donated Acer
• Adopted Cartes du Ciel as my planetarium platform
• Designed, built and installed a long-exposure device for the Canon
• Designed, coded and installed long-exposure software

Not too many changes then

I’ve been waiting all week for a gap in the clouds and tonight, even though the conditions are far from perfect, I took a chance and imaged M42 with 10 x 120 seconds at iso800. While focusing I noticed the collimation is out but the batteries are dead in my laser collimator so I won’t be able to do anything about it tonight. Maybe I can use out of focus bright stars to collimate, I’ll post some focusing images to show what I mean.

In hindsight, I wish I’d taken 30 sec, 60 sec, 90 sec and 120 sec images to allow me to make a HDR composite image, but this was only a test session to make sure everything works.

So here’s my M42, it’s 8 x 120 seconds stacked with DSS (DeepSkyStacker) and taken in windy conditions:

M42

M42 the Orion Nebula (iso800, 8 x 120 seconds, Canon 300d, Baader MPCC, Skywatcher 10" Newtonian, EQ6, EQMOD)

I’m happy with the round stars across the whole image, even with the windy conditions they’re better than I’ve ever imaged before.

Now I need some clear skies …

In an attempt to fix this I’ve bought some polystyrene insulation boards which I’m attempting to glue to the roof panels.  I’m not too confident about this approach and currently have only glued 2 panels to see if it works.

I’ve changed laptops so the “new” Acer is now set-up as the main controller and my long exposure software is all installed and tested (mental note: must get a photo of the controller).

I’ve run into some problems with the scope control but the weather is too bad to open the roof so I can’t run any tests. Basically the scope seems to point 180 degrees (12hrs) off target!  I’ve checked all the usual suspects like system time, location, software configuration and I can’t find the issue.  I have changed a number of things so tracking down the cause may take a while:

• Planetarium software changed to StarCalc
• ASCOM upgraded to 6
• New laptop installed
• EQAscom latest version

More to follow …

So what changes are happening at Ty Du? Well to start I was gifted an old Acer laptop from my sister-in-law (thanks Al) which may be old (the laptop but is streets ahead of the ancient model I currently use. In simple hardware terms I’m moving from 512MB to 2GB of RAM which will make a massive difference given the number of apps running simultaneously when imaging. The down side of the new (old) laptop is that it doesn’t have a parallel port and my long exposure cable for the Canon uses parallel. I knew this day would come but didn’t realize the trouble I’d have working around it.

I was thinking it would be easy to buy a USB to parallel converter (only £3 on amazon) and plug my existing cable into that but it seems these cheap parallel cables are designed for printers and not to run pin2 switching for “DSLR Shutter”. I pried the case open, prodded it with a multi-meter but I wasn’t getting the same control on the data lines as I would with a traditional LPT port so I splashed out another £3 for a USB to serial cable. I knew this wasn’t a direct replacement but after studying online circuit diagrams I was happy that connecting the RTS line from the serial adapter to the opto-isolator on my parallel adapter would solve the problem and be easy enough to do.

Well it would have been easy if they’d sent the right cable! doh! I’m sure a VGA splitter will come in handy one day, so after dropping it into my “odd cables” bag I set about working on plan “c”. Plans “a” and “b” both provided a working solution without changing software but plan “c” was much more radical. So here it is:

“Plan C”
I had an Arduino board (google it, it’s an awesome open-source project) lying around so I thought if I interface that to the opto-isolator I could use the microcontroller to open and close the camera shutter.

Hmmm, but then I won’t be able to use “DSRL Shutter” so I’ll have to write some timer software for taking multiple exposures. Oh and I’ll have to write some firmware for the arduino to allow me to control it through the USB port … what was I thinking.

So I did it, it took most of the afternoon to knock together the exposure timer and I wrote the firmware yesterday evening.

// Project	 :	canonDSLRtimer
// Author    :	Duncan Abraham
// Date      :  10-Dec-2011
// Version   :  1.000

void setup() {
  Serial.begin(115200);           			// set up Serial port at 115200 bps
  Serial.println("canonDSLRtimer v1.000");
  pinMode(13, OUTPUT);						// pushing pin 13 (LED) high at same time for visual reference
  pinMode(12, OUTPUT);  					// using pin 12 for the shutter trigger
  digitalWrite(12,LOW);						// set pin low
  digitalWrite(13,LOW);						// set pin low
}

void(* resetFunc) (void) = 0;

void loop() {
	while (Serial.available()) {
		byte inByte1 = Serial.read(); 		// read a character from the comm port

		if (inByte1 == 65 || inByte1 == 66 || inByte1 == 68 || inByte1 == 86 ){ //A,B,D,V
			if (inByte1 == 65) 				// A = shutter open
			{
				Serial.println("shutter open");
				digitalWrite(13,HIGH);
				digitalWrite(12,HIGH);
			}
			if (inByte1 == 66) 				// B = shutter closed
			{
				Serial.println("shutter closed");
				digitalWrite(13,LOW);
				digitalWrite(12,LOW);
			}
			if (inByte1 == 68) 				// D = RESET
			{
				resetFunc();
			}
			if (inByte1 == 86) 				// V = Show Version
			{
				Serial.println("canonDSLRtimer v1.000");
			}
		}
	}
	delay(10);
}

So that’s the arduino sketchbook .pde file that tells the microcontroller how to interact with the data coming down the USB connection.

Next step was the Windows software to control the arduino.  As you can see from the code above I set up a simple method involving a single character being sent:

• “A” – open the shutter
• “B” – close the shutter
• “D” – reset the Arduino
• “V” – display the version number

The Windows software was developed in C# and provides an interface to connect to the comm port, select exposure times etc and run the timer.

Port selection screen.  This screen presents a drop-down box showing all available comm ports on the PC.  When you pick a port and press “select” the application tries to communicate with the arduino by sending a “V” for version.  If nothing is returned the application tells you to try again

After selecting a comm port you are presented with the chance to select how many exposures you want to take, any delay before and after and the duration of each.  I’ve gone for all times in seconds to save confusion, but it would be easy enough to convert this to hrs:mins:secs in version 2 (maybe).

Finally, when you press the “START” button it goes into timer mode and starts counting the seconds and the exposures. 2 progress bars show completion of the current exposure and all exposures.

So that’s it, quite simple really but it works.  I’ve been down to the observatory and (after installing all required .Net libraries …) I was able to take several short exposures to prove the system works in principle.  I won’t know for sure until the weather changes.

What about the Christmas treats I hear you ask, well, finally I bought a Baader MPCC to turn my rubgy ball shaped stars into nice round points. Of course I couldn’t stop at that, the MPCC won’t fit into my standard rack and pinion Skywatcher focuser without me fitting the 2″ adapter. That would prevent me reaching focus with the DSLR. So I had to ask Santa for a low-profile, dual speed, crayford focuser as well .

I bought a 2″ skyglow filter some time ago, but without the correct fittings I wasn’t able to use it. Now it will screw into the bottom of the MPCC so I’ll have flat images with reduced orange glow – I can’t wait.

In the last few weeks I’ve:

• Installed the Atik 16ic as the main imaging camera
• Installed the QHY5 as my guide camera with all the driver issues associated with it!
• Adjusted the primary collimation on the main scope

It may not sound like much but those few changes have taken time to get right and I’ll need more clear nights before I’m happy with the results.

I’ve found that if I keep my guide camera exposures to 0.5 seconds I don’t get too much movement and I’ve been able to take images as long as 5mins.  After stacking the 5min exposures in DSS (Deep Sky Stacker) I thought the focus was out but it seems there’s just too much movement and the resulting stack looks more blurred than the individual frames.

I may suggest on the EQMOD forum that the software could include a timed shutdown option as I leave the system imaging overnight and hope the scope doesn’t get jammed against anything before I awake and rescue it.  So far I haven’t had any issues but if I could issue a “Park at 4:30am” command I’d feel a lot happier and may even sleep longer .

Images

So here are a few images from the last 2 or 3 nights. All have been stacked in DSS with curves and levels in Photoshop:

I’ve been looking through some of my older posts and updated Jan 2008 to include a piece on a supernova in NGC6946 for which my images were used to estimate the date as I had before and after images from the 16th and 24th January. SN2008S is given as official “birth” date of 01-02-2008 but my image from the 24th January clearly shows the SN to be visible.

After looking through the older images I’m tempted to put the Canon away for a while and see if I can take long guided exposures with the Atik16ic. The problem with the Atik is the small CCD offers much smaller field of view than the big CMOS sensor in the Canon which means that even tiny movements will result in egg shaped stars. I’ll have to dig out by other guide cam …. where did I put that?

All I need is a clear night!

I’ve spent some nights in the observatory since finishing the build last year, but I couldn’t get auto-guiding working even after investing in a dedicated guide scope and haven’t really produced anything worth shouting about.  In the last couple of weeks I think I finally have the guiding fixed and have successfully guided for over 3mins with only slightly eggy stars.  Imaging over 5mins totally over exposes due to the light pollution here in South Wales but I think if I can get enough frames at 3mins I should be able to start producing some good images for the gallery.  My collimation is slightly out and I need to invest in a Baader MPCC (not the first time I’ve said that) as the stars at the edge of the field of view suffer badly from coma.

All the images I have at the moment are waiting for processing so I’ll get them on here as time allows, but for now it’s good to be back

Comet Garradd August 2011

Another view of Comet Garradd Aug 2011

M81 and M82 14x120secs at iso 800

M101 showing Supernova PTF11kly

Not the best images I’ve taken but I’m working on it. The M101 image was taken between clouds to ensure I had an image of the supernova before it fades. Comet Garradd is getting brighter but not expected to peak until early next year. If it makes it to Mag 6 in September, as predicted, it could become the photographers favourite object for a month or so Funny how the one image has it green and the other blue, its all in the processing so maybe I need to redo them.

Where shall I start? The project is still not finished but an end is in sight. After the last post, I built the roof frame and managed to lift the roof into place on my own. I figured if the ancient Egyptians could build pyramids I could lift a roof. I’d be lying (again) if I said it was easy. A steel roof 10′ x 10′ with a wooden frame weighs … well lots, and lifting it into place required me placing wooden rails either side and physically lifting the roof past the tipping point to allow it to fall into place. I stopped for a breather after that!

With the roof in place I was able to complete the walls and fascia boards and move onto the rear rail assembly that will support the roof in a “rolled-off” position. Digging 2′ holes for the fence posts was easy enough, trying to hold a post upright and level whilst aligning it with the roof rail (which I couldn’t see) proved to be to too difficult and I eventually built the whole rear assembly upside down on the lawn. After my Herculean efforts with the roof I asked my brother to lend a hand to carry this into place. With a lawn that slopes making everything square and upright was a task. I propped the ends of the main framework on timbers to get it level before fixing the upright fence posts in place. A slight error on my part means one of the posts is not perfectly upright – but close enough. The photo makes it look worse than it is because the steel cladding on the shed runs out slightly where the fascia board pulls the top in. No really – I’m not making excuses.

So where are we – roof in place – rear assembly in place – oh I know what I missed: After getting the roof in place the heavens opened and it rained like I should have built an Ark not an observatory! To my horror the roof leaked. The only reason for buying the steel shed was to make sure the structure was weather proof! Ahhhh. I spent an afternoon with buckets and silicone sealant trying to make running repairs but the silicone washed out but luckily the buckets kept the floor from getting any wetter than it was. The floor wasn’t sealed, it’s made of a type of board that isn’t weather proof and the damp barrier was under it, so when the boards got wet I did worry a little. After several attempts to repair the leaks I got my brother over to help lift the roof off – the once heavy roof was now even heavier as the rails and cross supports where now in place! In hind-sight it was a 4 man job, but by the time we realised that we were past the point of no return. We stripped the roof boards off and re-assembled them, this time with a thick layer of black sticky roof repair goo between each joint and in all the screw holes. On either end we used roofing bolts instead of the provided screws and washers (these are self-tapping bolts with a built in fibre washer). Black goo oozing from the screw holes was dismissed as a necessary evil and the rebuilt structure was manhandled into place, now all I needed was rain to test it.

As luck would have it I didn’t have to wait too long and again AHHHH it leaked! Only in two places, 1 was a screw hole, the other a seam between 2 of the roof sheets. I fixed the screw hole by removing the screw and putting enough black goo over the hole to plug 20 holes, but better safe than sorry. The seam was another issue. The problem was where the sheets overlap. I ran a bead  of goo down the whole length of the seam and screwed through from the inside – pulling the two sheets together with goo squeezing out both sides.

So the roof is on, the rear frame in place – no leaks? still waiting for significant rain to test it – on to the wheels and rails. Running castors on a wooden beam will quickly wear a groove, I decided to buy some steel channel for the castors to run in. I decided 4 castors each side would be enough -  and if not I’d put some more on. Not exactly a scientific approach – but it worked. So how do you screw castors to a rail that’s upside down and weighed down with a roof. I have these clamps that work by pulling on a trigger to close them and pressing a release button to unclamp. by removing one end of the clamp and putting it on the other end it becomes a spreader! I used these to lift and hold the roof with wooden blocks just in case the roof fell while my arms were under it!  The steel was easy to work and I drilled and counter sunk the holes until I broke my counter sink bit, then I used the 20mm bit I’d used on the brake disk as a counter sink – that was fine. Rails in place, wheels in place – paint applied to all exposed steel – now it’s taking shape. Before the wheels and steel rails I was able to haul the roof back a few feet, but now I was able to run it fully off with one hand!

Exterior timber has been painted with wood preserver and the floor covered with wood-oil to waterproof it. I’ve built a wide shelf along the back wall to hold a laptop and any other bits and pieces. I’ve also run an armoured power cable the length of the garden and wired up a consumer unit with RCD and 4 x 13amp power sockets. I have a 6amp circuit for lighting but don’t have a light yet!

So here’s a few photos:

	Here’s a shot of the mount in place. I tried it to make sure it pointed north but the clouds came over before nightfall so I couldn’t get a sighting on polaris.  I’m happy there’s enough adjustment to get it aligned, even if the pier alignment is off.
	Here’s a shot of the observatory (careful not to call it a shed!) with the roof off. Construction still taking place so it still looks like a building site.
	Here’s the latest shot of the outside of the observatory.
	The locking mechanism. Likely to be a temporary solution while I  look for something more permanent. The clamp stops the roof rolling off and also keeps it down. I’ve also added some other clamps and locks to keep it all secure.
	Here’s a panorama of the inside of the shed at eye-level. It shows castors, rails, clamps and black goo if you look hard enough

Update 19:05 25-04-2010:

I’m done! I painted the pier and the brake disk, installed a power-line Ethernet adapter to give me network access and fitted a second hasp to the door. I bought 2 padlocks and fitted them as well as some other bits and pieces to help secure the structure.

All that’s left is to find a spanner that will fit under the brake disk to tighten the centre bolt that holds the mount in place. Nothing too serious but without this simple tool I can’t do any more. When done up the bolt is slightly recessed into the brake disk making it difficult to get any type of adjustable spanner (wrench) in there. It’s cloudy tonight so no rush – you can be sure it’ll rain for the next 2 weeks!

Hopefully the next post will be first light at Ty Du Observatory.

Watch this space …