2019-09-02, 08:54 PM
Hi,
Have you actually measured your faintest naked eye star at zenith on a dark night? It is very important for this parameter to be as accurate as possible. So if not, it may help to do so.
Globular clusters are difficult to rate, because like a lot of things, it depends on how you want to rate it. In a small telescope it will be unresolved as a hazy patch of sky. In a larger telescope you are resolving individual stars. This is going to be the case for a 10-inch Dob. So in this case, SkyTools selects a magnitude limit for the stars that will allow you to get a good view of the resolved cluster. This magnitude is used to determine the difficulty. Those stars are what are "detectable." As you can see, this whole process is going to be somewhat subjective. I am working on improving this for globular clusters in ST4 Visual.
As for NGC 6543, it is only 22 arc seconds in diameter. At the lower magnification used for finding you may be mistaking it for a star. At magnitude 8.3, something that compact really is going to be obvious. I suggest trying again and this time try to identify a slightly fuzzy-looking star near the center of the field, and when you suspect you have found it, switch to higher magnification. It should appear non-stellar at that point.
Clear skies,
Greg
Have you actually measured your faintest naked eye star at zenith on a dark night? It is very important for this parameter to be as accurate as possible. So if not, it may help to do so.
Globular clusters are difficult to rate, because like a lot of things, it depends on how you want to rate it. In a small telescope it will be unresolved as a hazy patch of sky. In a larger telescope you are resolving individual stars. This is going to be the case for a 10-inch Dob. So in this case, SkyTools selects a magnitude limit for the stars that will allow you to get a good view of the resolved cluster. This magnitude is used to determine the difficulty. Those stars are what are "detectable." As you can see, this whole process is going to be somewhat subjective. I am working on improving this for globular clusters in ST4 Visual.
As for NGC 6543, it is only 22 arc seconds in diameter. At the lower magnification used for finding you may be mistaking it for a star. At magnitude 8.3, something that compact really is going to be obvious. I suggest trying again and this time try to identify a slightly fuzzy-looking star near the center of the field, and when you suspect you have found it, switch to higher magnification. It should appear non-stellar at that point.
Clear skies,
Greg
Clear skies,
Greg
Head Dude at Skyhound
Greg
Head Dude at Skyhound