Some Imaging results with our 12" Orion-US Dobsonian & Watch House Standard Platform

 
 
Here we will be posting some of our results as we progress up the  learning curve of basic astro-imaging.

 

We have  been experimenting with a basic Phillips colour SPC 880 web cam (ca£20) and with the Phil Dyer Minitron B/W video camera system (ca£300)  and our 12" Orion-US Dobsonian on its Watch House Equatorial Platform .
 
VERY few decent nights here in Cornwall in 2011, but we will keep trying !

 

These cameras are not  high resolution instruments, 640x480 VGA resolution only, but are quite sensitive, and very nice for display on the monitor/laptop when group observing and for demonstration purposes etc . 
 

 

The Colour Phillips SPC 880  is only really suitable only for bright objects, ie moon and planets, but it is CHEAP and gives great results for a tiny outlay.

 

The Minitron video camera system is a much more sensitive, low light black and white camera, suitable for deep sky objects and can integrate frames on the fly to give "exposures" equivalent to about 5 seconds.

 

My Personal view ?  : have a go with a cheap £20 camera first,  and only then, if you get hooked, spend 15x to 20x more on a pukka setup. Of course if you get hooked... you can spend mega£ on cameras......

 

 

 


The Phillips SPC880 cheap colour camera :

 

These are available from Morgan Computers with the nescessary 1 1/2 nose piece for a song ie about £30 :

http://www.morgancomputers.co.uk/product_detail/10496/Philips-SPC880-webcam-Not-pre-flashed/

 

Here are a couple of  images of the moon, taken in November 2011, with the Phillips SPC880 web cam , about 30 seconds of video recorded at 30fps and then Registax 5 processed.
Simple compass alignment only of the platform, and average seeing, plus some wind .
 
 
 
 
 
 
 
 
 
 
Saturn was a target of opportunity one night in June 2011 so I had a go at a basic web-cam capture and we were amazed at the quality of the results.
Simple compass alignment only of the platform and average seeing.
 
 
 
The Image of saturn above was obtained from 2 minutes of video footage, processed in the free program Registax 5, selecting the best 50% of frames, stacking and optimising then a small adjustment using the wavelet functions.
You can see the cassini division on the LHS of the ring system, and the flattened shape of the planet is quite obvious.
 
 

Then I finally managed to get up at 3:30 am (!!) in June 2011 and do some imaging of Jupiter with the 12 " Orion Dobsonian and the Phillips  web cam . Image below was obtained by recording video of 1 minute length, 30 frames/second, with a 2x barlow then processing in registax 5.1. Alignment, stacking of the best ca 400 frames, then a wavelet and contrast tweak. Io is visible to the left of the planet.

 
 
 
 
The summer down here was mostly PANTS, daylight astronomy only ,  then in early November I "lucked out" as they say, and set up on Jupiter  again one evening on a breezy night, and as soon as I was at the eyepiece I realised that by chance a transit of Europa was in progress ! Furiously recorded a series of about 20 or so  30 sec to 1 min videos, adjusting focus, and exposure etc at 30 fps, using a 2x barlow with some windy moments, between the scudding clouds.
 
The outcome of processing one of these 30 second videos was probably our best image to date :

 

The transit of Europa on November 4th 2011, Imaged with our 12" US Orion Dobsonian, and a Phillips SPC880 web cam on a Watch House Standard Platform (on a breezy night) ,  from St Agnes, Cornwall , UK.
 

 

 

Simple compass alignment only of the platform and an image obtained from 30 seconds of video at 30 frames/second, processed in Registax 5.1, best 100 frames then combined and tweaked with wavelets.
 
We even got this image published in the local paper !!


The montage below shows the movement of Europa across Jupiter's disk  over about 30 minutes on the evening of Nov 4th 2011, taken from the best videos of the evening.

 
 

 
The  slideshow/video below covers the basics of how to image with one of these webcams, using a Dobsonian on a Watch House Platform and the raw video footage recorded on November 4th  as an example :
 
 
 

Basic Imaging with a Watch House Platform

 
 

 

The MINITRON black & white camera :

 

First Outing - Jupiter and moons and some deep sky adventures

 

Images and video below were taken on our first outing with the Minitron camera in 2011.

Seeing was not very good, as you can see from atmospheric wobble, ( especially on  videos we took at high mag of the moon and have not posted here) , but it was the first non-cloudy night for weeks  ! !

 
 

Tracking Jupiter with a Watchouse Platform

 
 
 

We overexposed Jupiter on purpose in order to capture all 4 moons, and so no detail of the planet is visible, but this gives an idea of the magnification / field of view of the camera when directly coupled to the scope, and the video demonstrates the efficiency of the tracking platform nicely.

 

 First Deep Sky targets

 

You can increase sensitivity on the Minitron by integrating exposures directly on the fly with this camera, and it then displays a sort of “time lapse” video which refreshes at the end of each integration period.

 

You can integrate up to 256 exposures, and the still image below is a frame from a video sequence of the ring nebula, M57 taken from a video which was recorded using 256 integrated 1/50th second shutter speed exposures for each frame. This integration dodge gives greater sensitivity for deep sky targets live viewing on the monitor, and should prove great for live viewing of deep sky targets in groups, and indeed gives much more detail than in the eyepiece view.

 

This gives an exposure equivalent to about 5 seconds, and so the video image updates each 5 seconds on the monitor when you are observing.

 

 
Focus could have been a little tighter, and a little over exposed ( this was a first attempt, between clouds !) and the moon was up so background sky was not dark, but you can clearly see the 2 stars inside the ring and the "hairyness" of the outer limbs of the ellipse.
 
Not too bad for a first deep sky live viewing attempt .
 
Bodes well for deep sky sensitivity once we get more experience ( ie we have some clear and dark nights to practice) and for stacking non-integrated images using registax etc
 
As this 5 sec exposure has given quite a is a bright image of a fairly dim object,  we could probably tolerate higher magnification too, and will try a screw in Barlow nosepiece.
 
 
We will also try the effect of a focal reducer, once we get  another nice night.
 
Using the tracking platform makes this camera super user friendly.
You can locate your object and center it in the eyepiece at 100 to 200x,  then remove the eyepiece, replace with the camera, play with the focus and Voila, your object is still in the centre of the field of view !
 
 
 Second Outing -  Jupiter at high magnification and the Moon, Minitron camera
 
Once again seeing was not very good, but we had a clear and not too windy night.
The video footage  below of Jupiter was shot with the camera zoom function set to ON ( ie 2x digital zoom)  and with the addition of a 1.6 screw in nosepiece Barlow . This set-up seems to give a magnification of at least ca 300 - 350x, as best as we can judge.
 Again the tracking motor is ON at the beginning of the sequence, then the motor is  turned OFF for 10 seconds, which gives the view you would have in a non-platform  mounted, ie normal,  Dobsonian and  then tracking is turned back ON again for the final part of the video .
 
 Again no post processing magic of any kind applied , so this is your live monitor view, which represents the eyepiece view.
 
 
 

Tracking Jupiter at high Magnification

 
 
Then we had a go at the moon, quite low in the sky so shows atmospheric wobble .
Using a fast shutter speed and again turning the tracking motor on an off to compare the view with a platform mounted dobsonian to a classical Dobsonian.
 
 

Tracking the Moon at high magnification

  
 
 
 
And finally, after downloading the freeware program Registax5, here is the enhanced image produced by the alignment and stacking of frames from the above video footage.
 
 
 
Not at all bad, considering the camera is only 750x580 pixels effective resolution, and digital zoom was on so its actually about 375x290.
 
Next decent clear night we will try getting higher magnification by barlow stacking , rather than digital zoom. 
 
 
 Third Outing - some deep sky attempts, Minitron Camera
 
 
 
This is a still image is from a video of stars and specifically double stars, in the clusters near Casseopiea. No digital zoom and no Barlow used, just the camera in place of the eyepiece .Some quite faint doubles have been captured and separated successfully.
 The Minitron camera was set to integrate 256 x 1/50th second images on the fly, so this represents an effective exposure of  5 seconds per frame.
Seeing was as usual not ideal and tight focus was nigh on impossible to achieve.
 
Then we had a go at the open cluster M52
 
 
 
Again the Minitron camera was set to integrate 256 x 1/50th second images on the fly, so this represents an effective exposure of 5 seconds.  Seeing was still not ideal and tight focus was even harder to achieve, but again some nice doubles captured and separated.
 
Then.......... the sea mist rolled slowly in, and everything went fuzzy, followed by all the kit getting very wet with dew.
 
Rapid end of session !
 
 
Fourth Outing - Almost Full Moon, but at last no clouds
 
So got set up and hitched up the DSLR and its adapter.
Rats ! can't achieve focus with the orion 12".
Shame as this worked OK with the Meade ETX 125.
So.... tried the trick that worked for the bino-viewer, ie use a screw in Barlow nosepiece into the camera T adapter and voila !, now we have focus.
Using the view finder to focus the scope and the result is below
 
 
 
 
Then the big black ones arrived and it rained.
 
 
Watch this space for our next attempt, and we hope some more deep sky targets, IF the sky ever clears and settles to good seeing down here ! !
 
 
 Fifth Outing - Moon and at last no clouds Minitron camera again
 
Seeing still not great but clear night at least. That is the penalty paid for living 100 yards from the sea, LOTS of water vapour in the air when the waves are breaking.
Another session on the Moon, at very high magnification.
 
 

tracking the Moon at High Power

 
 View through my Binoviewer and 2x20mm eyepieces was AWESOME, almost got exposure staying out in the bitter cold, and even the 16yr old daughter came for a squint, and was impressed.
 
Strange " Lights" on the Moon ! ! !
 
whilst visually observing the moon on Feb 14th 2011 I noticed a very strange effect. Looked like a group of lights hovering over a crater on the terminator. The lights were very bright and stood out really white against a very black background. High power resolved 7 or 8 individual points of light.  View with the bino viewer was really quite spooky !
The following evening I saw the same effect so I set up the minitron video camera, even though the seeing was rubbish, clouds and breaking waves putting lots of water vapour into the air.
The videos I got are below.
 

"Lights" over the moon ?

 
 
Same target but now with a barlow and digital zoom engaged, seeing still crap
 

Close up of "Lights" over the moon

 
 
Processed the frames in registax to get a single image, somewhat enhanced , shown below .
 
 
 
 
 Presumably this is an example of the light and shadow effects called  " Clair-Obscur " and not a group of VERY stationary UFOs hovering over the moon ! !
Nice web site for these effects can be found at http://the-moon.wikispaces.com/clair-obscur 
 

 
 Here are some nice " atmospheric" ( no pun intended !) shots of craters on the moon under reasonable seeing, using the Minitron camera, 30 second video capture and then processed with registax.
 
 
 
 
 
 
 
 
 
 
I like these images, as they give a real sense of 3D, and in some ways mimic what you see with the bino-viewers.
 
 
Well March was mostly PANTS with fog and cloud, but we had a few  clear nights , at last in the summer but LOTS of dew . !
 
 Below M13 taken with the Minitron, 30 seconds of video and processed in Registax.
 
 
 
And again with the minitron, and about 40 seconds of video frames this time processed in registax, Saturn at high mag ( 350x + ) using a barlow and digital zoom function .
 
 
 
 
 Not very impressive, bright objects are clearly not this camera's speciality, but see the Phillips web cam images , which are much better 
 
 
And finally the Globular cluster M53, 40 seconds video in registax again, no barlow .
 
 
 
 

 

Almost no imaging in the summer as the nights were so short, and also CLOUDY ! ! Autumn gave some short breaks in the clouds.

 


 

Probably our best image to date :

The transit of Europa November 4th 2011, Imaged with our 12" US Orion Dobsonian, and a Phillips SPC880 web cam on a Watch House Standard Platform on a breezy night ,  from St Agnes, Cornwall , UK.

 

Image obtained from 30 seconds of video at 30 frames/second, processed in Registax5, best 100 frames then combined and tweaked with wavelets.

 
 

Daylight Astronomy ? ?
 
Well very short nights and some sunny days in the summer  tempted us to have a go at solar observation for the very first time.
We could not find any obvious examples of Equatorial Platforms being used to track the Sun on the web, but the maths says it should work more or less OK.
As the sun's apparent motion in the sky is largely due to the Earths rotation, using a platform should allow us to dial this out and thus eliminate most of the normally observed eyepiece drift.
 
! ! NEVER TAKE CHANCES OBSERVING THE SUN ! !
 
ALWAYS USE A PROPER SOLAR FILTER
 
OBSERVING THE SUN UNPROTECTED CAN INSTANTLY LEAD TO PAINLESS BUT VERY SEVERE EYE DAMAGE.
 
SO.... we bought some Baader Planetarium AstroSolar TM saftey filter film, and then made a simple stopped down aperture adapter (light gathering power is NOT an issue when solar observing, but the cost of a full sized 12" solar fitler most certainly is ! !) by cutting a 2" dia  hole in one of the heavy plastic Orion 12" end covers.
 
 
 
 
 
 Duct taped the film in place over the hole with black Duct tape and then shrouded the truss tube dob to mimic a solid tube telescope, fitted the end cap so that it was not over a spider arm and off we go .......Oh and making sure to put the lens cap on the finder scope first of course , to avoid setting fire to my head, or anything else ......
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Simple compass alignment to set up the platform then place the dob on it.
Now locate the "target" by moving in azimuth until the shadow of the tube+mount indicate you are pointing at the Sun, and then sweep in altitude with a 2" wide field eyepiece and there it is in all its glory.
Watch the slow drift at 75x, turn on the platform drive and .... OK, works a treat !
Change eyepieces to higher mag 1 1/2" cross hair and adjust the speed a bit and virtually all the drift is eliminated at 150x.
 
Great ! The theory works !
YOU CAN TRACK THE SUN WITH AN EQ PLATFORM ! Two large sunspots in view and a couple of very small ones too.
 
Decided to be optimistic and have a go with the Phillips SPC880 webcam, just set at auto exposure etc and see what we got, and the result was a reasonable video of the Sun at about 200x ish mag.
Decent focus was unfortunately very hard to achieve due to passing clouds and shimmer in the atmosphere. Processed the video in Registax  and got the image below of a large sunspot, near the limb of the Sun.
 
 
 Well nights continued to be GARBAGE down here all summer , thick fog, clouds, rain, plagues of frogs and toads, you know the type of thing ( ie normal English summer at the sea side ) .
Continuing to observe the sun in place of real astronomy, got this image of multiple sunspots .
Again focus seems much harder to achieve with the web cam compared to a normal eyepiece, despite a clear sky ( ? ? ).
Recorded 2 min of video and processed with registax, best 300 frames optimised and stacked  +  a wavelet tweak.
 
 
 
So we can add solar observing to the ever growing list of what to do with your Watch House Equatorial Platform !