A belt of doubles

[FenlandPaul]

I was looking forward to getting out with the AR127L for a double star and planets session, but since I bought this fine looking scope from fellow SGLer Chris Lock it's been almost perpetually cloudy!  Any clear skies have coincided with other commitments or strong winds.  Tonight I had a window of an hour or so and was looking forward to unwinding at the eyepiece.  The moon was full, washing out anything south of about 3rdmagnitude, but it was transparent with occasional cloud, reasonable seeing and a lovely frost in the air.

Mintaka (delta Orionis) was my first target.  At x38 in the 32mm TV Plossl, the primary was brilliant white with a slightly blue, fainter companion.  It was clearly resolvable at this power.  At x100 in the 12mm, chromatic aberration caused Mintaka itself to have a purple halo and the field stars seemed rather drowned out.  The best view was in the 20mm at x60; 6 brighter field stars (roughly the same brightness as the secondary) were scattered across the field, with a further dozen fainter stars in the background.  Mintaka was framed beautifully, augmented by an orange satellite which passed silently through the field of view, providing a lovely colour contrast.

Struve 751 (double in Orion) was next, easy to find near the middle belt star, Epsilon.  751 formed, along with another star of similar brightness, the base of an isosceles triangle with Epsilon at the apex.  In the 32mm at x38, the double was easily split, with the primary maybe 2 magnitudes brighter than the secondary.  At x100, the brighter star had a slight yellow hue with the secondary appearing slightly blue to my eye.

Alnitak (zeta Orionis).  The left hand star in Orion's belt.  At x120 (using the 20mm and Barlow) and x133 I thought I could detect a slight elongating of the star, but no clear split.  In fact the field appeared slightly fuzzy (perhaps because my barlow and those particular eyepieces are Revelation-branded so maybe not the best around!!).  Separation is stated in the Cambridge Double Star Atlas as 2.4" with a 1.8 magnitude difference, so it should be possible.  

I finished the evening with a brief look at Jupiter, which had now cleared the roof top.  All 4 moons were strung out and Io had just emerged from behind the Jovian limb.  The polar and equatorial belts were all on display clearly, even at this low elevation.  Were it not for a heavy schedule at work this week I would have stayed up a bit later and looked at it at higher altitude.    

I think I'm going to enjoy this scope.  It's remarkable value for money, even if new, and it seems to do well with doubles and was very impressive on Jupiter.  It's given nice views of the moon (I'm determined to make the moon my friend this year!) and I saw a lovely occulation of Aldebaran a few weeks back.  Chris called this scope the "planet killer" - I think he's right.  But I need to sort out my eyepieces.  Even my TV Plossl is showing some really significant pin cushioning, with the field of view seeming to "roll" rather than "drift" past.  I've always neglected eyepieces, which I suppose is a bit like putting cheap tyres on  a performance car, so I need to make amends and research and plan a long term investment in eyepieces to suit my observing needs!

Glad others also got clear skies last night!

Paul

[Stu]

Glad you got out with the scope Paul, I'm sure you will have some fun with it.

A good idea to get some eyepieces sorted to get the best out of the scope, and nothing worse than a cheap Barlow!

Alnitak split quite easily in the Tak 4", I forget which mag but it was below x150 so you should be able to do it.

[Piero]

What a wonderful tale of an enjoyable night!  Really nice details! I don't think I saw Struve 751..  noted! 

Good luck with your eyepiece investment!

Piero

[laudropb]

Very nice report. A most enjoyable read. Best of luck with your new scope.

[alan potts]

A lovely report and good reading whilst clouds amass here as they have done now for 3 days after being perfectly clear all day. 

Alan

[F15Rules]

On ‎24‎/‎02‎/‎2016 at 21:54, Stu said:

Glad you got out with the scope Paul, I'm sure you will have some fun with it.

A good idea to get some eyepieces sorted to get the best out of the scope, and nothing worse than a cheap Barlow!

Alnitak split quite easily in the Tak 4", I forget which mag but it was below x150 so you should be able to do it.

Nice report Paul, thank you for posting :-).

I'd echo Stu's remarks above: I have no problem splitting Alnitak on reasonable nights with both my 4" apo and 5" AR127l scopes. The 4" is easier as the image is "cleaner" and with no CA to distract, but the AR127l does it well too, if using decent eyepieces and enough magnification.

I used good quality Japanese orthos at 7mm and 9mm. These give 171x and 133x respectively, and you need decent magnification to get "in" close enough to see the split (it's only about 2.2" or so). But the higher powers also darken the sky background, so increasing contrast, which again makes it easier to see, especially if the Moon is about as it has been all this week.

Unless you have a decent barlow I would steer clear of them. I recently bought an APM 2.7x apo barlow which is the absolute "dogs", but not cheap at around £130 shipped. But you can find decent older ones like the Celestron Ultima x2 for around £40-£50 in good used condition. Also, the Revelation versions are actually quite good for around £38-£45 new, both in 1.25" and 2" barrels.

Take a look at M42 and the Trap with the AR127l on a good dark night before Orion is gone...it's stunning, and the Bat Wings spread right across the FOV: see if you can get the E and F stars in the Trap too!

Dave

[Special K]

Sounds like a lovely scope!  At f/9.5 this must be very effective on doubles and planets.  Good luck with the agony of eyepieces...........it's such a world spoiled for choice and can be so hard to make a decision

 

[FenlandPaul]

18 hours ago, F15Rules said:

Nice report Paul, thank you for posting :-).

I'd echo Stu's remarks above: I have no problem splitting Alnitak on reasonable nights with both my 4" apo and 5" AR127l scopes. The 4" is easier as the image is "cleaner" and with no CA to distract, but the AR127l does it well too, if using decent eyepieces and enough magnification.

I used good quality Japanese orthos at 7mm and 9mm. These give 171x and 133x respectively, and you need decent magnification to get "in" close enough to see the split (it's only about 2.2" or so). But the higher powers also darken the sky background, so increasing contrast, which again makes it easier to see, especially if the Moon is about as it has been all this week.

Unless you have a decent barlow I would steer clear of them. I recently bought an APM 2.7x apo barlow which is the absolute "dogs", but not cheap at around £130 shipped. But you can find decent older ones like the Celestron Ultima x2 for around £40-£50 in good used condition. Also, the Revelation versions are actually quite good for around £38-£45 new, both in 1.25" and 2" barrels.

Take a look at M42 and the Trap with the AR127l on a good dark night before Orion is gone...it's stunning, and the Bat Wings spread right across the FOV: see if you can get the E and F stars in the Trap too!

Dave

Thanks Dave.  I definitely think my eyepieces are holding back my abilities with all my scopes.  My only premium glass is a TV Plossl, which gives wonderfully sharp views in the fracs (and much improved in the dob) but the pincushion (at least that's what I think it is) is really pronounced.  As the field drifts past, the image seems to climb to the centre and then drop off towards the other side.  Putting the moon slightly off centre shows the distortion most noticeably.  The fact that I wear glasses (althouhgh thinking about contacts) and have an astigmatism should make choosing the right eyepieces even more challenging!!

[Stu]

1 hour ago, FenlandPaul said:

Thanks Dave.  I definitely think my eyepieces are holding back my abilities with all my scopes.  My only premium glass is a TV Plossl, which gives wonderfully sharp views in the fracs (and much improved in the dob) but the pincushion (at least that's what I think it is) is really pronounced.  As the field drifts past, the image seems to climb to the centre and then drop off towards the other side.  Putting the moon slightly off centre shows the distortion most noticeably.  The fact that I wear glasses (althouhgh thinking about contacts) and have an astigmatism should make choosing the right eyepieces even more challenging!!

Paul, you sound like a prime candidate for a few Delos or Pentax XW eyepieces ??

[alan potts]

1 hour ago, FenlandPaul said:

Thanks Dave.  I definitely think my eyepieces are holding back my abilities with all my scopes.  My only premium glass is a TV Plossl, which gives wonderfully sharp views in the fracs (and much improved in the dob) but the pincushion (at least that's what I think it is) is really pronounced.  As the field drifts past, the image seems to climb to the centre and then drop off towards the other side.  Putting the moon slightly off centre shows the distortion most noticeably.  The fact that I wear glasses (althouhgh thinking about contacts) and have an astigmatism should make choosing the right eyepieces even more challenging!!

Paul,

I was like this when I bought a 26mm Nagler from one of the members on site, I used it in a test between the 24mm Meade UWA and the Nagler. I was using the 12 inch Meade at around X125 and made the mistake of looking at the moon. I hated it after that and kept the Meade though other members sing its praises, I feel I was a bit silly looking back, but I know what you mean. The 31mm Nagler is almost the same but I never use this on the moon.