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My Main Telescope - C14 and Paramount ME

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

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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

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 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.


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« 28th February 2010 - Abell Clusters | Main | Leyland Observatory Primary Optics upgraded »

Using a plate solution to centre an object and synch the telescope.

Friday night (19th February) was clear until about 1130 p.m. I managed to image over 100 galaxies. It is so much easier now with the centred images but I have a long way to go to build up a sufficient library of reference galaxies with so few clear nights here. I have been experimenting with synching into the T-Point model to see the effect. This is not a recommended approach but I believe that it is quite an effective method of keeping objects centred. I think the ideal way of adding points to the T Point model is to take an image, solve the plate and then synch into the T Point model if necessary or map on the image link centre rather than spend time centring a star and mapping that. If you have a good plate solution this is extremely accurate and also avoids identification errors – it just does not matter where you are pointing. This was the first random area of sky that I imaged, synched on the image link centre and mapped into the model.

(Unknown 1)


Carrying out a plate solution gave 19 stars used with an RMS position error of  0.09 arcseconds.



Here are the above image and the chart produced by the Sky to confirm the pattern recognition



I now added labels from "The Sky" which identifies many of the stars on my original image.


The image link information in the table below gives me the actual  centre of the image (i.e. where the telescope is actually pointing so by Synching on this position corrects the pointing error on the telescope at those coordinates.

 So once the Synch was carried out all successive images that night (100 plus) were exactly centred.