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Splitting Izar

Jim Smith

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wxsatuser

wxsatuser

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Managed to image the Double Double the other day but Izar was a different kettle of fish.

On some frames I thought the companion was just there but I tried everything to no avail.

The difference in brightness and the seeing was just against it that time, will keep trying. though.

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Stu

Stu

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Last night was clear and the seeing was good. I tried Izar again and this time I saw the secondary just very slightly above the primary (180x). It seemed to be lurking in the first diffraction ring just like Stu said. I checked in Sky Safari and it confirmed the relative positions on the component stars.

I also split the "double double" in Lyra as suggested. That was somewhat easier to do than Izar even though the separation is less. I suppose the similar magnitudes helps.

Nice one Jim, did you catch the different colour on the secondary, bluish?

The double double is easier for exactly the reason you describe, more equal magnitudes. The hardest doubles are close ones of very different magnitude where the primary drowns out the secondary in the glare.

Stu

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MahlerMoonMan

MahlerMoonMan

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Hi guys, would you expect an ED80 to split Izar? If yes, what's the recommended mag? It sounds like it's posing a challenge to larger apertures so I'm wondering if it's worth my bother .... If I ever again get a clear night up here!! :D

Thanks,

Donaldo

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Stu

Stu

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Hi guys, would you expect an ED80 to split Izar? If yes, what's the recommended mag? It sounds like it's posing a challenge to larger apertures so I'm wondering if it's worth my bother .... If I ever again get a clear night up here!! :D

Thanks,

Donaldo

Hi Donaldo,

I can do it with a TV76 so I am sure the ED80 will do it. Fracs often have an easier time than newts on doubles due to the tighter star shape and lack of diffraction spikes.

I would just try at around x150 ish, can't remember what I normally use but try around there and see what you get.

Good luck

Stu

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chiltonstar

chiltonstar

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Hi guys, would you expect an ED80 to split Izar? If yes, what's the recommended mag? It sounds like it's posing a challenge to larger apertures so I'm wondering if it's worth my bother .... If I ever again get a clear night up here!! :D

Thanks,

Donaldo

Yes, it's quite easy, given decent seeing. One of my favourite doubles - like Albireo but prettier due to the close proximity and the strong colours.

Chris

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Stu

Stu

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Had a look at this again tonight with the TV85 and nag zoom which gives between x100 and x200.

It split very nicely at the lower end, and it looked fabulous at x200, the colour difference seemed more obvious at the higher power.

I tried a 5mm Hutech Ortho at x120 which gave a very nice, crisp split.

I also tried a 7mm BGO giving x86. At this mag, could I split it? My imagination was saying yes, but I suspect it was more that I knew it was there! Will check again next time but overall some very nice views between the clouds.

Stu

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chiltonstar

chiltonstar

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Same experience as Stu. I had a patch of clear skies hovering around Izar, so I got my ED80 out for a brief while. Very dewy, because of the rain.

At x150, Izar was nicely split with the secondary a greyish-slate colour, situated on the diffraction ring of the orange-yellow primary, with good clear space between the Airy disks. Looked much the same to me, but smaller, at x73.

Always a lovely double..

Chris

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Stu

Stu

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Same experience as Stu. I had a patch of clear skies hovering around Izar, so I got my ED80 out for a brief while. Very dewy, because of the rain.

At x150, Izar was nicely split with the secondary a greyish-slate colour, situated on the diffraction ring of the orange-yellow primary, with good clear space between the Airy disks. Looked much the same to me, but smaller, at x73.

Always a lovely double..

Chris

I reckon your eyes are much better than mine Chris!! They were very close together at x86 so x73 must have been very challenging. Good stuff though!

Stu

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Stu

Stu

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I cant split double stars...................my telescopes wont see through this blooming cloud, though i did see the Alberio split at the Astronomy centre last week

I sympathise Jules! Last night was a case of popping the scope out quickly to take advantage of small breaks in the cloud. Similarly to Chris, I just happened to have a clear patch on a couple of occasions over Mars and Izar, very fortunate because they were exactly what I wanted to observe!

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Jim Smith

Jim Smith

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Tried the split of Izar again last night. Seeing was so-so. Nothing at all obvious at 90x.  Just visible at 180x. As for star colours...I think I will have to wait for a night with better seeing before I can hope to honestly see a difference.  I did happen across 61 Cygni as well...very pretty. 

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avtaram

avtaram

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Definitely split Izar tonight using my ED 120 with 10mm Delos combined with the 2.25 Baader Zoom Barlow giving a magnification of 202.5 .

Izar was orangey yellow and its companion was blue. The companion was at 11 o'clock relative to Izar and quite close in.

I tried splitting Izar with the 12" Dob but failed even though the collimation was spot on. Izar was just too bright and masked the companion.

I tried the Double Double with the 12" Dob and just about got a split but not clean. Using the ED120 I got a clean split.

The 12" Dob not so good on doubles but great on DSOs, The ED120 not so good on DSOs but great on doubles.

Didn't manage to do a sketch as I was too busy playing with my recently acquired Altair Astro AZ mount.

Avtar

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jetstream

jetstream

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Congrats on Izar Avtar :icon_salut: ! I have just split it with my new toy-120ED- 8mm gave a clean split and 6mm seemed to bring out the vibrant colors.I love these 2 stars.Tonight I tried Delta Cygni for the first time with the frac and it was much easier than expected,this scope seems to split stars pretty good,I used my 3-6 zoom on it with success.The 10" dob did these splits,but harder for it-I love dobs,but refractors sure have a place in the arsenal too.

Izar is a beautiful double,and a friend revisited

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avtaram

avtaram

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if the spec of the field of view is correct in that sketch I am sorry to say I don't think you managed a split of Izar. if the 0.6 degrees tfov and magnification is accurate then this equates to 36 arc minutes across the field. Izar's companion is only about three arc seconds from the primary and the one in your sketch is much further away than this (more like several arc minutes - maybe 8 arc minutes). I don't know if there is a coincidental blue star at this distance from Izar but could you have seen this?

Just been checking my notes, and you are right it's not Izar.

I did two sketches, not on the same night, one of Izar ( so I thought ) and one of Delta Bootis.

Looking at the two sketches, both seem very similar, which leads me to the conclusion that it was Delta Bootis I was looking at.

I have since managed to view Izar and can see the difference, I just need to sketch it now.

Thanks to Moonshane and BigMakStutov for pointing out the mistake.

Avtar

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Stu

Stu

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Twice recently I've managed to spend some time trying to split entirely the wrong star! It's tricky when they are very tough (eg Lambda Cygni), because until you split it it is not obvious!!

Fortunately it was dark and nobody noticed apart from the foxes ......... ;-)

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