Moon and Porrima

Yes, Darren.
Porrima is very nice.
But did you succeed in splitting it?

Kind regards,

Aubrey.

I'm afraid not Aubrey.

While I love my XT6, I'm beginning to think that it is not a great scope for splitting stars. It manages to split the straight forward ones such as Mizar and Alcor; Epsilon Lyrae; and Delta Bootis; but it struggles on others. You might recall that I found it quite difficult to split Izar. Of course they say that a bad workman blames his tools, so maybe it has to do with my lack of experience splitting doubles. Regardless, I'll keep at it.

Clear skies,

Darren.

Your scope should be more than capable of splitting a huge number of doubles, Darren.  Perhaps you should consider making an off axis mask.  A smaller aperture should help, as it allows you to use higher magnification when the seeing allows.
I am not going to insult you by asking if your scope is collimated.

Paul

Hi Darren.
I hope you are keeping well with all this crazy social distancing.

Okay, let us compare Izar with Porrima.
Izar's magnitudes are: A = 2.6. B = 4.8. Sep = 2.8". PA = 347 degrees.
Porrima's magnitudes are: A = 3.5. B = 3.5. Sep = 2.9" or almost 3" right now.PA = 358 degrees.

Therefore we can easily figure out that Porrima is the easier to separate.
Izar B companion is fainter than Porrima.
It is logical to presume that Porrima is more likely to be split through your fine telescope.

Last night (Friday) I did seek out Porrima with my own eyes. It was relatively easy to see before I looked into any telescope. And I did find it quite difficult to locate in my small apo. Whenever I had a "bright" star in the centre of the field of view, I proceeded to observe it in the main scope. No - that's not Porrima. This happened no less than 3 times! I then discovered that Porrima is low from my vantage point. When I did observe the correct star, my scope was almost parallel with the ground I was standing on. I found it easy to split at 112X. That is the same magnification I use to split Izar on a good night. I did split Izar earlier.

If you wish to try again to observe Porrima, Darren, please do make sure you have the right star. That is my advice.

By the way, I have now moved to Coma Berenices. Canes Venatici has become impossible for me because of my Berlebach mount and the proximity of the focuser. But I ought to return to C V later in the summer.

Kind regards to you and your family,

Aubrey.

Hi Aubrey and Paul,

I tired three times to post my message last night, but I never got to finish it. I wanted to thank you both for providing such useful advice and suggestions. Based on the information you provided I reckon I was observing the wrong star. I doubt it was a collimation issue because I collimate the scope before each session. And please don't think you'd insult me by asking whether I had the mirrors collimated Paul...I don't think like...I only see such an approach as it is: helpful.

In terms of the axis mask, not sure what it is so I'll follow-up on that - thanks.

Again, very many thanks for your replies. I'll let you know how I get on over the next week,

Clear skies, and enjoy Coma Berenices Aubrey.

Darren.

And thankfully all is well with the family. The fine whether is certainly helping as we can enjoy the back garden. I hope things are good your end Aubrey and Paul too.