My Astronomy




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.


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« Sunday 19th October 2014 Mars meets Comet Siding Spring | Main | A study of the star cluster NGC 6716 Part 1 »

NGC 6716 Photometry Part 2

I was watching the video on You Tube "Seeing in the dark" (Go here to see the video and the associated interviews)and came across a reference to Samuel Palmer's painting of the comet of 1858. I paused the video and Googled the painting to discover it had been stolen from its 89 year old owner earlier this year by a con man! See this article.

From "Seeing in the Dark"


NGC 6716 Photometry continued.

The B image below shows NGC 6716 with 25 target stars, 1 comparison star and 1 check star


 These are the B results


 After going through a similar process with the V image these are the V results



So I have measured the brightness in B and V bands of 25 of the stars that appear to be in the cluster NGC 6716.

Of course some of these will be line of sight stars either in front of or behind the cluster. I have not taken into account the extinction of light by the atmosphere or the interstellar medium. I may try that later but first of all I will estimate the temperature of the stars by calculating B-V in an attempt to do some real science.

To be continued..........