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Morning all,

As I was up early this morning and it was still dark I decided I would take a look at epsilon lyrae.

I set up my heritage 130 and put my eyepieces outside to cool down.

Went and made a cuppa only to find light cloud everywhere when I returned. After about 15 minutes the sky was clear and my eyes had adapted.

My first stop was albireo, I love this pair and I never tire of looking at it, I find the best view of this is with my bst 8mm. 

Next I jumped over to Lyra, found vega, just above it I could see epsilon lyrae just about with my naked eye so put my red dot finder over it, looked at it with my 25mm, nicely split into a pair of stars, looked again with my 8mm, still only 2 stars, put my 8mm into a 2x Barlow but still only 2 stars. 

I focused on them the best I could and put them at one end of the field of view and watched them drift through hoping the more I looked the more clearer the view would be and maybe I would see them split into four.

Unfortunately it wasn’t to be. I’m pretty sure I was looking at the right stars, they were 2 stars, the same brightness one above the other with the bottom one slightly to the left off centre and they were just above Vega.

Can this be done with this kind of set up, how much magnification is needed.

Many thanks.

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It certainly should be do-able with your scope. Did you notice that the stars were elongated at all? They are basically orientated at 90 degrees to each other, one pair in one direction, the other at 90 degrees. At x162 which is I think what you used, the elongation should be clear even if the split is not so it is possible you were on the wrong pair.

Newts tend to have a harder time of this than refractors because fracs tend to show tighter star shapes due to their lack of central instruction. I’ve split them with a decent frac somewhere down at x55, but find x80 or so normally gives a pleasant view. In the Newt I think you will be needing the sorts of mags you were using, at least until you have got them identified and can experiment.

Cooling, collimation and seeing are key to splitting them. They are nice and high at a convenient time at the moment so that makes things easier, give your collimation a check first and then give it another go. Actually I have a Heritage 130P so I will try that if I can and see what mag I need.

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I can’t recall seeing them elongated, I tend to see the spikes  of light too much to see great detail, I don’t know if that’s the scope or my eyes though.

I would appreciate it if you split them in your heritage and let me know what magnification is needed.

It could very well be that I was just looking in the wrong place!

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Certainly doable, but as Stu says Newtonians can struggle a little sometimes with tight doubles. I much prefer to observe doubles if possible with a ‘frac rather than my C8 SCT as this too struggles sometimes with doubles a lot more than my ‘fracs. Saying that also the seeing can also make a difference, so if it wasn’t good last night then this can make tight doubles harder to spot as they sometimes get lost in the difraction rings and  lost around the stars you are observing, so carefully observing is required sometimes. 

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3 hours ago, leo82 said:

I would appreciate it if you split them in your heritage and let me know what magnification is needed.

Will do. The rain is forecast to clear to this evening so will give it a go and report back as I can't remember from the last time.

I do think there is quite a chance you were looking at the wrong pair so make sure your finder is aligned on Vega and then shift across to the DD which you can see naked eye anyway I should think.

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21 minutes ago, leo82 said:

Is this double double claseed as a tight split?

what size frac do you use? @Knighty2112 and what mag works for you?

It's not that tricky actually.  We had a discussion on another thread that it is theoretically resolveable in a 50mm scope (which Chris proved). Personally I've done it in a 60mm refractor relatively comfortably. In a 4" frac I would say it is trivial, largely because the pairs are relatively even brightness, one pair is slightly harder because one is less bright.

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If a 60mm frac can do it surely a 130mm can do it.

I must have been looking at the wrong pair, skimming through my cdsa I may have found an answer.

 

sticker 1 shows 2 bright stars with dimmer stars around them, I remember seeing a chain of stars like at the right of sticker 2 not far from the 2 stars.

In my defence tho it was 4 in the morning when I decided to do a bit observing

091F0BE8-BCD8-43E7-B7FB-A593BEBE8377.jpeg

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39 minutes ago, leo82 said:

What app is that you use? It looks really helpful.

SkySafari. It is excellent. I have the Pro version which you won’t need, I believe the standard version is now free

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Ah that’s probably the same stars I was trying to split. 

If I can stay awake long enough I will try again later, apparently there’s only 2% chance of cloud. Chances are though it will be too high!

Is the finder only available on the pro version of safari? or is it because I’m using the mobile version?

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6 minutes ago, leo82 said:

Ah that’s probably the same stars I was trying to split. 

If I can stay awake long enough I will try again later, apparently there’s only 2% chance of cloud. Chances are though it will be too high!

Is the finder only available on the pro version of safari? or is it because I’m using the mobile version?

Which version are you using? I think you can do it in most versions but can’t remember. In version 5 and 6 you do it in different ways, but you should be able to set your kit up then select the scope and eyepiece and choose to display the field of view circle. You can also display Telrad circles ie 0.5, 2 and 4 degrees.

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7 hours ago, leo82 said:

Is this double double claseed as a tight split?

what size frac do you use? @Knighty2112 and what mag works for you?

Can see them in my 66ED-R which is my smallest ‘frac. Can’t remember what mag I need to split them with it. I’ll check it out tonight. The forcast is for clear skies after 10pm. From top of my head I think I can split them with a 10mm EP, but I’ll double check later on. 

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23 minutes ago, Knighty2112 said:

Can see them in my 66ED-R which is my smallest ‘frac. Can’t remember what mag I need to split them with it. I’ll check it out tonight. The forcast is for clear skies after 10pm. From top of my head I think I can split them with a 10mm EP, but I’ll double check later on. 

If it is around 400mm focal length like many of these scopes then I more likely to  be a 5mm or even shorter for x80 ish. Lowest I’ve heard of is about x50 in a 100mm

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31 minutes ago, Stu said:

If it is around 400mm focal length like many of these scopes then I more likely to  be a 5mm or even shorter for x80 ish. Lowest I’ve heard of is about x50 in a 100mm

You might be right there Stu. I was most likely thinking of my C8 with that. I’ll check still later on when I can.

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Well, Mrs Stu seems to be engrossed in some abomination called Gossip Girl ;) so I popped out with the Heritage 130P and OMC140 side by side on the Ercole to see where we got to.

I kept the 24mm Panoptic in the Mak giving me x83. The Double Double split quite easily with this combo. It just shows the difference between the two scopes, 2000mm focal length vs 650mm for the Heritage so only x27 in that scope. Popping the Nag zoom in gave me x108 and I was surprised that the split was really quite easy, lovely bullseye stars. Moving to a 7mm BGO for x93 maintained the split quite clearly, so finally the 9mm (don't have an 8mm) at x72. Well, it was very tight, but when seeing was stable the split was just about there.

I was impressed with the Heritage on this target, it gave a good result, surprising to a degree. Moving to Izar, the Mak split it easily still with the 24mm, but the Heritage seemed to struggle more with the different brightness of the components. It took a fair amount more power to split and the secondary was still harder to pull out of the messier primary.

Last target, briefly was M13, at similar mags it was just that bit better resolved and a little brighter in the Mak reflecting the additional aperture as much as anything I guess.

Interesting comparison, impressed with both scopes really.

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Thanks for taking the time to help me with these stars.

I too went out last night around midnight, how do you guys manage to look at targets right overhead? I did my best trying to find vega, I think I got it in the eyepiece but couldn’t see the double double, trying my best to keep in mind where the double should be with stu’s diagram. After a few minutes searching I had to give up as I was starting to get neck ache, I did manage to get another look at albireo though and then swung the scope around and managed to split eta Cassiopeia quite easily with the 8mm. I think I need to observe epsilon in the early morning or wait until it’s better positioned.

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8 minutes ago, leo82 said:

Thanks for taking the time to help me with these stars.

I too went out last night around midnight, how do you guys manage to look at targets right overhead? I did my best trying to find vega, I think I got it in the eyepiece but couldn’t see the double double, trying my best to keep in mind where the double should be with stu’s diagram. After a few minutes searching I had to give up as I was starting to get neck ache, I did manage to get another look at albireo though and then swung the scope around and managed to split eta Cassiopeia quite easily with the 8mm. I think I need to observe epsilon in the early morning or wait until it’s better positioned.

I have my Heritage on a tripod set reasonably high so I can look through the RDF quite comfortably.

Can you see the Double Double with the naked eye? My skies are around Mag 5 at best and it is reasonably clear on good nights which makes popping the finder on it quite easy. It is worth persevering whilst it is high because the split will be easier looking throughout the less atmosphere, although it is still quite possible lower down.

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