Almach

[CHRlS]

Hi,

Just before I went to bed, the sky was clear so I went outside and started doing some unaided observing. As I was making my way from the "Square" of pegasus and through Andromeda towards Perseus, I remembered there was a double star in between the latter two.

I'm new to the world of double stars so I quickly got out my Heritage 130p and lined it up. Through the 25mm it was just one star. I put the 25mm in my 2x Barlow and again it was still only one star. At this point I should mention I have astigmatism but don't wear glasses whilst observing as i like to squish my eye inside the eyepiece and take in the whole field of view. However, I put my glasses on and looking through the eyepiece again I could clearly see two stars, putting my glasses on had corrected my vision to make out the second star. I put in my 8mm and then the 8mm in my 2x Barlow, all whilst wearing my glasses. This last combination showed off the orange/yellow and blue/white stars perfectly.

I was only outside for a quick 10 minutes with not having anything planned, but came back inside happy with how my observations turned out.

 

[RobertI]

Well done, Almach is one of the most beautiful doubles in the sky, did you notice the colour difference between the two stars? Albireo in Cygnus is another double of the same quality. I think many people with astigmatism observe with their glasses on, and choose eyepieces with good “eye relief” to help with this. I’m sure some experienced observers with astigmatism will offer some advice on this if you are interested. 

[Mr Spock]

It's a very pleasing sight. Doubles can be very absorbing. There are quite a few eyepieces with 20mm of eye relief, I'm sure glasses wearers can recommend some.

[Zermelo]

44 minutes ago, CHRlS said:

Hi,

Just before I went to bed, the sky was clear so I went outside and started doing some unaided observing. As I was making my way from the "Square" of pegasus and through Andromeda towards Perseus, I remembered there was a double star in between the latter two.

I'm new to the world of double stars so I quickly got out my Heritage 130p and lined it up. Through the 25mm it was just one star. I put the 25mm in my 2x Barlow and again it was still only one star. At this point I should mention I have astigmatism but don't wear glasses whilst observing as i like to squish my eye inside the eyepiece and take in the whole field of view. However, I put my glasses on and looking through the eyepiece again I could clearly see two stars, putting my glasses on had corrected my vision to make out the second star. I put in my 8mm and then the 8mm in my 2x Barlow, all whilst wearing my glasses. This last combination showed off the orange/yellow and blue/white stars perfectly.

I was only outside for a quick 10 minutes with not having anything planned, but came back inside happy with how my observations turned out.

 

Yes, Almach is a perennial favourite. Regarding the astigmatism in your eyesight, you should find that it is less of a problem with higher magnifications (it actually depends on the size of the "exit pupil" of the light entering your eye).

[CHRlS]

2 hours ago, RobertI said:

Well done, Almach is one of the most beautiful doubles in the sky, did you notice the colour difference between the two stars? Albireo in Cygnus is another double of the same quality. I think many people with astigmatism observe with their glasses on, and choose eyepieces with good “eye relief” to help with this. I’m sure some experienced observers with astigmatism will offer some advice on this if you are interested. 

I did notice the colours, it's such an amazing sight to see two different colour stars sitting close together on a black background and being framed within an eyepiece. I have also seen Albireo and Almach in my eyes is a mini me version. I don't know if that's just me being biased as Albireo is the first double star I was able to split?

I am currently using the standard skywatcher 25mm and an 8mm bst starguider. I believe this to have 16mm eye relief. I should probably upgrade my 25mm for this reason alone.

Any advice on astigmatism and eyepieces would be most appreciated. 

[CHRlS]

2 hours ago, Mr Spock said:

It's a very pleasing sight. Doubles can be very absorbing. There are quite a few eyepieces with 20mm of eye relief, I'm sure glasses wearers can recommend some.

I think it's fair to say that it can be addictive, especially the different coloured ones. 

[CHRlS]

2 hours ago, Zermelo said:

Yes, Almach is a perennial favourite. Regarding the astigmatism in your eyesight, you should find that it is less of a problem with higher magnifications (it actually depends on the size of the "exit pupil" of the light entering your eye).

It will now stay on my target list for anytime it's visible. I've just read a little on pupil size and now understand why it's worse at lower magnifications. 

[Spile]

It’s a fine double and great colour contrast too. Doubles are good friends for those of us with light polluted skies.

Edited November 4, 2023 by Spile

[lunator]

Chris, it is a lovely double.

There are lots of colourful pairs. Almach and Albireo are 2 showpiece pairs.

Cheers

Ian

[CHRlS]

2 hours ago, Spile said:

It’s a fine double and great colour contrast too. Doubles are good friends for those of us with light polluted skies.

I do have light polluted skies, so double stars seem to be goods targets to observe.

[CHRlS]

50 minutes ago, lunator said:

Chris, it is a lovely double.

There are lots of colourful pairs. Almach and Albireo are 2 showpiece pairs.

Cheers

Ian

I think I've set the bar high, picking out show piece stars for my first targets.