Rigel Double & Others In Orion

[Adirondack Astronomy]

A few weeks ago, on just about the only clear night, I took a break from imaging to look at Rigel. I enjoy viewing double stars but for some reason I never looked at Rigel before.
I was impressed by the pair.

I was wondering what is the separation and magnitudes of the two. I was using a 10 inch f/12 instrument and was wondering what would be the small scope that could be used to split Rigel?

Also, what are some other good doubles in Orion?

[clydec]

Originally Posted by Adirondack Astronomy John

A few weeks ago, on just about the only clear night, I took a break from imaging to look at Rigel. I enjoy viewing double stars but for some reason I never looked at Rigel before.
I was impressed by the pair.

I was wondering what is the separation and magnitudes of the two. I was using a 10 inch f/12 instrument and was wondering what would be the small scope that could be used to split Rigel?

Also, what are some other good doubles in Orion?

John,

I agree that Rigel is a fun double. Rigel A is about .20 mag and it's companion, B is around 7 mag. The separation is 9.5 arc seconds. It's a tougher split than the specs indicate because of the brilliance of Rigel A. I often split it in my TV-85 and use the quality of split and magnification required as a barometer for the seeing. Normally, it will split in the 55x-65x range unless it's a really bad night. If I can split it below 50x, I know I have an exceptional night. I can also split it in my 70mm Ranger, but it takes around 65x-75x. Oh, I think I remember reading that Rigel B is also itself a very close double. I don't remember the aperture required, if any, that might split it. It's sure a tiny pin prick in my TV-85!

Iota Orionis is also fun and just south of it are a couple of interesting Struve stars, #'s 745 and 747. Also, give Alnitak (Zeta) a look. It's a beautiful double reminding me somewhat of Izar, though not as colorful to my eye. I'm sure you're familiar with the system Sigma Orionis up close to Alnitak, but give it a look if you haven't in a while. I always enjoy it. I can make out the 4 stars of the system in the 40x-50x range on a good night. There's probably a lot more in Orion for your scope, but I'm more familiar with what's good in my 85mm scope.

Clyde

[pizwiz]

Just a thought on splitting close doubles.
I always use TV Radians for the purpose. To me, they seem to be the sharpest eyepieces around, with the Orthos running a close second. But the radians are much more comfortable to use.
BTW, when I bought my first Radian eyepiece (a 4mm), I thought the high Price was a pure rip-off and I called Mr. Nagler just about every name in the book. My old 10mm Ploessl with a Barlow did just as well, I felt.
That was until a really good night came along and I decided to give this expensive piece of junk another try before I ditched it. It blew my socks Off !!!
These eyepieces really shine on those great nights when their sharpness can really be fully utilized. Now they are my hands-down favourites for fine detail work.
True, they do not have the super-wide FOV of some of the others, but that is of no consequence for fine detail work such as Planets and doubles.

Adolph

[clydec]

Originally Posted by pizwiz

Just a thought on splitting close doubles.
I always use TV Radians for the purpose. To me, they seem to be the sharpest eyepieces around, with the Orthos running a close second. But the radians are much more comfortable to use.
BTW, when I bought my first Radian eyepiece (a 4mm), I thought the high Price was a pure rip-off and I called Mr. Nagler just about every name in the book. My old 10mm Ploessl with a Barlow did just as well, I felt.
That was until a really good night came along and I decided to give this expensive piece of junk another try before I ditched it. It blew my socks Off !!!
These eyepieces really shine on those great nights when their sharpness can really be fully utilized. Now they are my hands-down favourites for fine detail work.
True, they do not have the super-wide FOV of some of the others, but that is of no consequence for fine detail work such as Planets and doubles.

Adolph

I agree about the Radians. I've had a bunch of 5mm eyepieces as that f/length yields a nice 120x in my scope. My 5 Radian is my favorite for all applications that I've used and splits doubles as well as any occular I've tried. 20mm's of eye relief is actually a little too much for my liking, but a couple of clicks of the Instajust does the trick.

Clyde

[Adirondack Astronomy]

I like using the Takahashi LE eyepieces for double observing. They have good eye relief and the color is very accurate. The LE 2.8, 3.6 and 5 mm have ED glass elements and add no false color to your views. The Radians give my eye a dark area or blind spot in the ceter of the eyepiece on the Mewlon 250.

I enjoy trying to discern the colors of double stars and the Tak LE's are very good to do that with especially the ED ones. To my eye the Radians always added a slight yellow cast to my views.

Here are the specs:LE Oculars offer long eye relief and 52° field of view for 5mm ED through 50mm and 42° field of view for 2.8mm ED and 3.6 ED. All LE oculars 2.8mm through 7.7mm use ED glass. All are fully multi-coated and parfocal.

They do not have a widefield of view for deep sky but are fine for planets and double stars.

(I like the TeleVue two inch 17mm & 22 mm Nagler type 4 for Deep Sky)
Thanks!

[pizwiz]

I can't possibly disagree. When it comes to this quality of eyepieces, you are in the realm of personal preference.
Just the difference in the individual's eyesight and sensitivity will make a person prefer one over the other.
That's why I am a great advocate of trying out as many different optics, Telescopes, eyepieces etc. at star parties as possible and don't pay any heed to all the techno-babble out there. Those folks are all correct in what they say, but that doesn't mean it necessarily applies to you. Experiment !, Experiment!

Adolph

[Rigel58]

Someone say Rigel?

Actually, Rigel is a very pretty double - one that I come back to often. If it is out, it can be a indicator as to how good or bad double stars are going to be depending on how easy it is.

I can view it rather easily with my TV-60 at 60x and higher.

John..

[pizwiz]

For these types of objects my favourite Telescope is the Orion 120mm F/8.3 refractor operated at F/21.
It has very sharp optics and beats my 6" Refractor in these tasks.
At 100X to 250X it produces wonderful images.

Adolph

[leicaguy]

Originally Posted by Adirondack Astronomy

A few weeks ago, on just about the only clear night, I took a break from imaging to look at Rigel. I enjoy viewing double stars but for some reason I never looked at Rigel before.
I was impressed by the pair.

I was wondering what is the separation and magnitudes of the two. I was using a 10 inch f/12 instrument and was wondering what would be the small scope that could be used to split Rigel?

Also, what are some other good doubles in Orion?

John,

In Orion I enjoy Sigma, Meissa (Lambda), Alnitak (Zeta), and of course Rigel and the "Trap". I often find myself getting emersed in Orion. I swing to Orion for a "quick" look at something and end up staying for hours!

A couple of weeks ago, before the Siberian weather hit, we had great seeing here in the Mid-Atlantic region. On a couple of nights I was able to clearly see the "E" star with my TV76 and both "E" and "F" with my NP101. This is very rare for this area because the normal state of seeing is mediocre at best. I really enjoy it when I can take full advantage of my scopes' potential.

Bill