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My Telescopes

My Main Telescope - C14 and Paramount ME

My new Paramount MyT and 8-inch Ritchey-Chretien Telescope

MyT Hand Controller

My Meade 12 inch SCT on a CGEM (Classic) Mount

My 4 inch Meade Refractor with Sky Watcher Guidescope and ZWO camera on a CGEM (Classic) Mount

Skywatcher Star Adventurer Mount with Canon 40D

 

My Solar setup using a DSLR and Mylar Filter on my ETX90

DSLR attached to ETX90. LiveView image of 2015 partial eclipse on Canon 40D

Astronomy Blog Index
About the Site

 I try to log my observing and related activities in a regular blog - sometimes there will be a delay but I usually catch up. An index of all my blogs is on the main menu at the top of the page with daily, weekly or monthly views. My Twitter feed is below. I am also interested in photograping wildlife when I can and there is a menu option above to look at some of my images. I try to keep the news feeds from relevant astronomical sources up to date and you will need to scroll down to find these.

The Celestron 14 is mounted on a Paramount ME that I have been using for about 10 years now - you can see that it is mounted on a tripod so is a portable set up. I still manage to transport it on my own and set it all up even though I have just turned 70! It will run for hours centering galaxies in the 12 minute field even when tripod mounted.

 

My Recent Tweets
Saturday
Nov142009

Testing Imaging at f/10 instead of normal f/6.3

At my normal focal ratio of f.6.3 images are approximately 20 minutes square which gives a good field of view but means that many galaxies are quite small. Also there does tend to be vignetting of the image. Whilst incorporating a new external focuser to get around image shift problems I thought I would try imaging at f/10 and check the practicality of centring the images (at the smaller field of view) for a galaxy run. On 9th Nov the sky was clear with drifting cloud which eventually became thick cloud - limiting the test. I tried it out with one object - NGC 744 - see the image below.

Clearly it is quite well centred. Here is the Deep Sky Survey Image - courtesy of The STScI Digitized Sky Survey.

The above image was obtained from STScI by completing the table below

The plate solution is shown here - 21 matched stars - RMS 0.08 which is a good astrometric solution.

This (as represented in the first image above) shows that the camera is not North aligned  - the Position Angle is given as 347.57 degrees. There was not time to rotate the camera to the 360 or 0 degree position as clouds set in. The matched stars on the image are shown here.

This is the image plotted onto the Sky Chart solution showing that it is indeed NGC 744

 

 and the Object Information Box

 

 

and the exact match of the Sky chart to the image. Note the direction of North corresponding to the discussion above.

 

 

Friday
Oct162009

Galaxy Run 16th October 2009

I managed to image 329 Galaxies tonight - some of which were obscured by cloud I might add which drifted by from time to time!

 

Monday
Oct122009

Galaxy Run 12th October 2009

I managed to image 345 galaxies on this run but many were of poor quality because of the low altitude and associated haze and light pollution.

Sunday
Oct112009

Galaxy Imaging Run

A fairly clear night with some drifting light cloud.  A continuous run produced images of 243 galaxies - mainly small and faint. These were blinked with previous images in the template library although not all could be checked because some were being imaged for the first time. In some of the "slices" too many galaxies had been included so the synchronism with the rotation of the Earth "slipped", and later images had moved across to the West of the Meridian. However there was no need to move the dome slit at all during the run.

Thursday
Oct082009

Galaxy Imaging 8 October 2009

A bright Moon tonight with 207 galaxies imaged

Monday
Oct052009

Martin Mere 4 October 2009

There were over 10,000 Pink-Footed Geese visible at Martin Mere yesterday with more flocks coming in at frequent intervals.

 

 

In addition I managed to photograph a Kingfisher from the hide on a post in the stream in front of the hide.

  Kingfisher Martin Mere

 There are quite a number of whooper Swans there now.

 

 

Saturday
Sep192009

Galaxy Template Library Creation

The major problem with Supernova hunting if you have a dome is the dome itself. Unless is is automated (which mine is not) you have to keep pushing the dome around as required by the sequence of galaxies to be imaged.

One solution to this is to synchronise the galaxy set being imaged with the movement of the sky. I am trying to do this by imaging in 30 minute wide RA "slices". By selecting the sequence of these slices to be at least half an hour behind the Local Sidereal Time these slices are near "vertical "at lower altitudes.

This means that the RA axis hardly moves and the Dec axis does all of the work - also meaning that the telescope only has to move vertically - i.e. parallel to the dome slit!

As one slice is completed - just before the galaxy crosses the meridian - the next slice - half an hour of RA to the East is started, maintaining its 30 minute RA eastward separation from the meridian.

I had an initial successful run at this last night allowing me to image 175 galaxies in a couple of hours or so, with magnitudes brighter than 15.  All of this without having to move the dome slit! In fact I was in my sitting room with a small wireless laptop on my knee showing the images coming in and showing progress through the galaxies - through the use of VNC - a freely downloadable bit of software.  If clouds appear I can spot this on the image and rush out to close up the dome if necessary.

With my field of view of 20' X 20' and 30s exposures many of these galaxies are very small and difficult to see but are definitely there and a bright supernove could be visible. Of course larger brighter galaxies are imaged as well.

The images are going into a single folder allowing any database galaxy (template) to be detected by name in Grepnova when it is re-imaged (image). Blinking can then be used beween template and image to identify any potential supernova - or intruding minor planet or other moving object of course!

Fortunately there is a mechanism for checking online to detect minor planet locations in the vicinity of galaxies imaged.

 Some images taken last night are shown below. They are all 20' X 20' with an exposure of 30s. NGC images link to the relevant image in the DSS Survey

 

 NGC 6971 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PGC 64696

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NGC 7042

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NGC 7241

Saturday
May092009

Supernova 2009bv

Supernova 2009bv as reported in The Astronomer Electronic Circular 2547

Saturday
May092009

Supernova 2009bw as reported in The Astronomer Electronic Circular 2547

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