More doubles under a bright moon

[RobertI]

The rare sight of a clear sky demands some observing, even under bright moon. 102ED plus Baader zoom (30-90x) plus Starsense atop the AZ4 made for some pleasant double viewing. Using the Astronomical League’s list of top 100 doubles in Sky Safari led to me to some really pretty doubles in Cepheus, Cassiopeia and Bootes. They were all very nice to look at, but two stood out:  the first was HR8281 embedded in the Elephant Trunk nebula (which I couldn’t see!) - this is a lovely triple, with a yellow primary and a dimmer secondary either side around 8” away, one seems bluish and the other greenish (yes I know green stars don’t exist!). The other was actually two doubles in the same field of view, Kappa Bootis and Iota Bootis, just in the same FOV at 90x but much better at lower magnification. 

 

Edited July 31, 2023 by RobertI

[Ratlet]

It's always weird when you try to explain nice doubles.  I'm not sure what the criteria is but some of them just look amazing!  I'll need to check these out.  Next purchase is going to be a Starsense and hoping to get more doubles in with it.

 

Great report and delighted you got some clear skies.

Edited July 31, 2023 by Ratlet

[RobertI]

1 minute ago, Ratlet said:

It's always weird when you try to explain nice doubles.  I'm not sure what the criteria is but some of them just look amazing!  I'll need to check these out.  Next purchase is going to be a Starsense and hoping to get more doubles in with it.

 

Great report and delighted you got some clear skies.

Totally agree! It’s hard to make the descriptions interesting, some definitely have colour, usually yellow or pale orange, occasionally blue white, but the dimmer secondaries are hard to identify the colours. I have been trying to estimate the separations and have been within 20-30% but not sure that makes for interesting reading! 

[josefk]

I'm a fair way through that AL doubles list @RobertI - i've really enjoyed it/am really enjoying it. You have to sketch them for the pin badge if that kind of thing floats your boat. I'm childish - i want the pin badge 🙂. TBH having to sketch them (and make certain specific notes) has been an excellent learning experience and has improved my observing discipline for doubles no end.

[RobertI]

2 minutes ago, josefk said:

I'm a fair way through that AL doubles list @RobertI - i've really enjoyed it/am really enjoying it. You have to sketch them for the pin badge if that kind of thing floats your boat. I'm childish - i want the pin badge 🙂. TBH having to sketch them (and make certain specific notes) has been an excellent learning experience and has improved my observing discipline for doubles no end.

Interesting to hear. I have occasionally tried a doubles sketch, but don’t think I’ve got the right technique! Feel free to include any sketches of the above doubles, it would be interesting to see, and might bring my descriptions to life a bit.  

[josefk]

I'm embarrassed to say there's no "technique" to see here 😂 - just plots (I would like to render the more zoomed in diffraction rings and colour type sketches you see of doubles but i never seem to get to it...)

[josefk]

BTW the 3rd one is pretty much "by the book" for the AL programme (i hope). Mag (diff), colour, PA and p estimates with location, kit and sky quality annotation. Cheers

[RobertI]

Very nice sketches, a good rendition of what I saw, I like the format too. I’ve only tried to estimate the colour and separation but I can see how doing brightness and position angle would encourage being longer at the eyepiece. I try to estimate PA when observing very faint/close doubles to eliminate any doubt! Thanks for posting the sketches.

[The60mmKid]

Yeah! STF 2816 (HR 8281) is one of my favorites! And it's so easy to find thanks to Herschel's Garnet Star, its lovely neighbor. And isn't that cluster that envelops it just beautiful?

[The60mmKid]

Also, I love the color contrasts of Iot and Kap Boo. I enjoy viewing them at low magnification so that they share the FOV and then increasing the magnification, which, to my eyes, makes the colors stand out more vividly.

[Mr Spock]

I think I'm going to start drawing doubles instead of just writing them down. It's just nicer to have a visual record.

[Spile]

I think my time would have been looking at those doubles rather than trying to glimpse M101 in my less than ideal skies. Many thanks for the report and associated media.

[paulastro]

On 01/08/2023 at 00:14, RobertI said:

The rare sight of a clear sky demands some observing, even under bright moon. 102ED plus Baader zoom (30-90x) plus Starsense atop the AZ4 made for some pleasant double viewing. Using the Astronomical League’s list of top 100 doubles in Sky Safari led to me to some really pretty doubles in Cepheus, Cassiopeia and Bootes. They were all very nice to look at, but two stood out:  the first was HR8281 embedded in the Elephant Trunk nebula (which I couldn’t see!) - this is a lovely triple, with a yellow primary and a dimmer secondary either side around 8” away, one seems bluish and the other greenish (yes I know green stars don’t exist!). The other was actually two doubles in the same field of view, Kappa Bootis and Iota Bootis, just in the same FOV at 90x but much better at lower magnification. 

 

Well done having some clear skies, excellent descripttions of double stars, and good use of Starsense.

[Richard N]

I’m a doubles fan too. I find that not everyone “gets” them. I was chatting to our gardener this week. I mentioned that I had set some pads in the lawn for my tripod. This prompted a discussion about astronomy. He turned out to be very knowledgable and even suggested a double that I hadn’t observed yet (Rigel). Maybe there are more doubles fans than I thought?

[RobertI]

1 hour ago, Richard N said:

I’m a doubles fan too. I find that not everyone “gets” them. I was chatting to our gardener this week. I mentioned that I had set some pads in the lawn for my tripod. This prompted a discussion about astronomy. He turned out to be very knowledgable and even suggested a double that I hadn’t observed yet (Rigel). Maybe there are more doubles fans than I thought?

Sounds like your gardener is pretty knowledgeable! Yes I know what you mean about people not ‘getting’ doubles, especially beginners. Perhaps they are an acquired taste. 🙂

[josefk]

15 hours ago, Mr Spock said:

I think I'm going to start drawing doubles instead of just writing them down. It's just nicer to have a visual record.

With apologies to Rob for spamming his thread - it occurs to me Michael with your big doubles lists you'll need a good filing system if you start drawing them. LOL. FYI EP boxes make good containers for index cards (reduce, reuse, recycle!)..

.

 

[Mr Spock]

My intention is to use a sketch pad in the field. Then when back inside redraw them in PaintShop Pro, save them as jpg under a suitable file name Such as STF3041, BU936 etc along with the date, so STF3041 20230802.

I've not finalised it yet so it's a bit rough, but, something like this:

White on black, as opposed to a sketch, means I can add subtle colour when required. File name is 'STT215 20230425'.

[josefk]

nice @Mr Spock - if i didn't spend all day in front of screen i'd be tempted to do the same because that approach will archive really well. You could even print a load of blanks off for the initial in field sketch.

[JeremyS]

51 minutes ago, Mr Spock said:

My intention is to use a sketch pad in the field. Then when back inside redraw them in PaintShop Pro, save them as jpg under a suitable file name Such as STF3041, BU936 etc along with the date, so STF3041 20230802.

I've not finalised it yet so it's a bit rough, but, something like this:

White on black, as opposed to a sketch, means I can add subtle colour when required. File name is 'STT215 20230425'.

Looking good. Would be worthwhile adding field orientation.

Have you tried photographing your sketch and inverting the contrast in paint shop, rather than starting another sketch from scratch?

[Mr Spock]

My sketches are messy