Doubles anyone ?

[gaseous (Patrick)]

Thanks gents, cloud permitting I will make 52 Ori my b!tch tonight.

[bigjoe (JOSEPH)]

Originally Posted by gaseous

Thanks gents, cloud permitting I will make 52 Ori my b!tch tonight.

I was going to Re attempt 52 Orionis also Patrick..but guess what ..not enough offerings to the Cloud Gods this week ..once again thwarted.
You'd think plenty of squashed blood sucking Mozzies would be enough of an offering, really you would.

bigjoe.

[Tinderboxsky (Steve)]

At last, a clear night here south of Hobart so tackled Orion doubles despite the bright near full Moon.
Scope: Vixen NA140SS refractor with LVW eyepieces: 8mm-100X, 5mm-160X and 3.5mm-229X.
Transparency looked good - difficult to tell with only one day to a full Moon. Seeing was good, say 9 out of 10. The more difficult targets were at just over 30 degrees elevation unfortunately, which I thought might be a problem.

Rigel @ 100X - straight forward and demonstrated that seeing was looking okay. It is a fine sight; bright Rigel and the companion a brilliant spot. The Vixen throws up some false blue on such bright star, so I won’t try to report a colour.

31 Orionis @ 100X - Primary a yellow/orange with the companion a faint speck.

Rho Orionis @ 100X - Primary a light yellow and the companion a clear very distinct pin point.

Sigma Orionis @ 100X - this is one of my favourite FOV's. The bright primary dominates the grouping, appearing whitish with a hint of yellow. Companion C was faint but clear. The brighter companions D & E appeared pale white with a greenish/blue tinge. The nearby Struve 761 close double in the same FOV was clear. A number of other stars completed the field.

Zeta (Alnitak) @ 100X - appeared elongated with hints of a figure “8” with regular moments of better seeing. Colour appeared white-blue. The faint wide companion C was clear. There was a clear, steady split at 160X A & B.

32 Orionis @ 160X - appeared as definite figure “8” with regular clear splits in moments of better seeing, colour pale blue-white. Clear, steady split at 229X.

52 Orionis @ 160X - appeared as a tight figure “8”, colour pale yellow-white. Difficult but clear, steady split @ 229X.

So, a successful night. Despite my earlier concerns that the elevations might be too low, I was able to split all of the targets. Thanks for the list Joe.

[gaseous (Patrick)]

Those cloud gods are hard to placate...

I've got to thank you and Steffen for the good advice Joe - I've never really hunted tight doubles (tight by my standards at any rate), and have never really pushed the 8" dob past about 250x except for planets, but the 2x Barlow with the 7mm Celestron you sold me did the trick. 52 Ori was split with moderate comfort at 343x, and was still OK at 400x with a cheap 6mm skywatcher plossl. I found turning off the goto tracking and let it drift across the field allowed for more stable moments of seeing. Thanks again - looking forward to next month's list!

[bigjoe (JOSEPH)]

Originally Posted by Tinderboxsky

At last, a clear night here south of Hobart so tackled Orion doubles despite the bright near full Moon.
Scope: Vixen NA140SS refractor with LVW eyepieces: 8mm-100X, 5mm-160X and 3.5mm-229X.
Transparency looked good - difficult to tell with only one day to a full Moon. Seeing was good, say 9 out of 10. The more difficult targets were at just over 30 degrees elevation unfortunately, which I thought might be a problem.

Rigel @ 100X - straight forward and demonstrated that seeing was looking okay. It is a fine sight; bright Rigel and the companion a brilliant spot. The Vixen throws up some false blue on such bright star, so I won’t try to report a colour.

31 Orionis @ 100X - Primary a yellow/orange with the companion a faint speck.

Rho Orionis @ 100X - Primary a light yellow and the companion a clear very distinct pin point.

Sigma Orionis @ 100X - this is one of my favourite FOV's. The bright primary dominates the grouping, appearing whitish with a hint of yellow. Companion C was faint but clear. The brighter companions C & D appeared pale white with a greenish/blue tinge. The nearby Struve 761 close double in the same FOV was clear. A number of other stars completed the field.

Zeta (Alnitak) @ 100X - appeared elongated with hints of a figure “8” with regular moments of better seeing. Colour appeared white-blue. The faint companion C was clear. There was a clear, steady split at 160X.

32 Orionis @ 160X - appeared as definite figure “8” with regular clear splits in moments of better seeing, colour pale blue-white. Clear, steady split at 229X.

52 Orionis @ 160X - appeared as a tight figure “8”, colour pale yellow-white. Difficult but clear, steady split @ 229X.

So, a successful night. Despite my earlier concerns that the elevations might be too low, I was able to split all of the targets. Thanks for the list Joe.

Cheers Steve..I see that green tinge also in Sigma's D......stars arent supposed to be greenish ,but thats the contrast I see also.
C is faint on the other side of the rest...52 yet to be cracked...all in a lovely field with Struve 761 and nebulae nearby.
Rho Orionis, an easy gem when viewed high up.

bigjoe.

[bigjoe (JOSEPH)]

Originally Posted by gaseous

Those cloud gods are hard to placate...

I've got to thank you and Steffen for the good advice Joe - I've never really hunted tight doubles (tight by my standards at any rate), and have never really pushed the 8" dob past about 250x except for planets, but the 2x Barlow with the 7mm Celestron you sold me did the trick. 52 Ori was split with moderate comfort at 343x, and was still OK at 400x with a cheap 6mm skywatcher plossl. I found turning off the goto tracking and let it drift across the field allowed for more stable moments of seeing. Thanks again - looking forward to next month's list!

Pat...
Thats a good trick what you did with the tracking....and a good Plossl of 6mm or 9mm and Barlow, is all you need in most scopes for all the DOUBLES here ...my next attempt at 52, Im going to really crank up the power , probably well over 350x!

bigjoe.

[Merlin66 (Ken)]

You may also be interested in the Journal Of Double Star Observers

http://www.jdso.org/

Lots of interesting observations and comparison data.

[bigjoe (JOSEPH)]

Originally Posted by Merlin66

You may also be interested in the Journal Of Double Star Observers

http://www.jdso.org/

Lots of interesting observations and comparison data.

Thanks for this Ken..interesting article on students observation of Delta Orionis for all here too.

bigjoe.

[Stonius (Markus)]

Originally Posted by gaseous

I found turning off the goto tracking and let it drift across the field allowed for more stable moments of seeing. Thanks again - looking forward to next month's list!

I'm curious about the theory behind this. How does the tracking of the scope deliver a less detailed view?

Best,

Markus

[gaseous (Patrick)]

Originally Posted by Stonius

I'm curious about the theory behind this. How does the tracking of the scope deliver a less detailed view?

Best,

Markus

Hi Markus,

I've found the GOTO tracking at very high magnifications on doubles and to a lesser extent planets can tend to make the view a little "jerky" as the gears adjust/track, so turning it off removes this jerkiness, and seems to allow for better seeing as the target drifts across the field of view. I then just use the direction arrows on the hand controller to pull it back across every so often. Don't take this as a slight on the goto - I wouldn't be without it and any alleged jerkiness is non-existing on DSOs and other lower-mag/wide field targets.

[Stonius (Markus)]

Originally Posted by gaseous

Hi Markus,

I've found the GOTO tracking at very high magnifications on doubles and to a lesser extent planets can tend to make the view a little "jerky" as the gears adjust/track, so turning it off removes this jerkiness, and seems to allow for better seeing as the target drifts across the field of view. I then just use the direction arrows on the hand controller to pull it back across every so often. Don't take this as a slight on the goto - I wouldn't be without it and any alleged jerkiness is non-existing on DSOs and other lower-mag/wide field targets.

That's interesting. Sometimes if Im trying to resolve very small details on a planet I feel like it helps to turn off the cooling fans on my scope momentarily. Maybe its the same sort of thing?

[gaseous (Patrick)]

Originally Posted by Stonius

That's interesting. Sometimes if Im trying to resolve very small details on a planet I feel like it helps to turn off the cooling fans on my scope momentarily. Maybe its the same sort of thing?

Quite possibly - anything that causes even the slightest vibration can screw with the view I reckon.