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From 3.5" to 1.25" under excellent conditions


jetstream

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You know, after these cloudy/snowy periods come the cold, and dark skies and clear skies, very clear skies. Tonight is such a night and I wanted to revisit the 90mm APO triplet and its optimum 1.25" set up.

So what first, hmmm- how about the Pleiades Bubble?

This object is very unique, with my 200mm f3.8 "shoving it right into my eye"...easy actually but the fracs were giving me grief with it... that is until I obs it about on and off for hours for many nights with the little newt. There is a bit of history, now for the present...

Tonight using the 16T5/SV90mm f7/mirror diag the Bubble showed very well, sections of it any way, pretty happy I can see this in the frac now! Pleiades Bubble tip...up the mag a bit, try many eyepieces and its not that hard under truly dark skies. Start at Merope... Have fun!

M42 was stunning, bright mottled green all over the place, huge overall and the core was spectacular! Again the 16T5 took first. Now with a UHC this scope comes alive on bright nebula, Monkeyhead and Rosette were fine indeed and the Flame was pretty fric ken good :icon_biggrin:.

I'll cut the list short saying M81,M82 were really really good lol! M51's tight little puff balls showed brightly and with separation, The Owl neb and companion were in the same FOV easy and of course no filter. Hey whats that faintish galaxie over to the left of M81 a bit...it showed in direct vision anyhow.

My short list is now the 32TV plossl,25 TV possl and the 16T5 Nagler  and I must further continue the tryouts for the medium and high mag work.

 

PS this was a great night with about 100 objects observed, but I didn't want to bore ya :grin:

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Really interesting Gerry! I'd never heard of the bubble until you mentioned it (possible on an earlier post too?). I sometimes wonder if the sky surrounding the Pleiades seemed less than empty, but I have rightly or wrongly attributed this to an optical illusion - I figured in the absence of other factors the sky would seem darker in the heart of the cluster due to the contrast against the brighter stars. This one is going to need a more careful look!

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Lovely report Gerry - a treat to reach under grey clouds with rain dripping down the windows :smiley:

"All I ask is a small scope under a dark sky and a star to steer her by ....." (well I did change the Masefield line just a little bit :smiley:)

 

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If this is boring, then carry on boring me Gerry :)

I had no idea what the Pleiades bubble was until I found this sketch on Cloudy Nights. Is this what you see Gerry?

My own experiences of the nebulosity around M45 are mixed, I believe I have seen it, but I often struggle to convince myself that it is not condensation on the objective!

IMG_8965.JPG

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Very interesting report, Gerry!

I've never heard of the Pleiades Bubble before. Researching on the net, I found Mel Bartels website www.bbastrodesigns.com/6inchF2.8/

showing a lot of beautiful sketches of very faint nebulosity regions, that can only be seen with extremely fast widefield scopes under perfect skies.

Some of them might be within the reach of my 8" f/4 Hofheim Traveldob, paired with the 2" 30 mmf  77° AFOV Wild Heerbrugg eyepiece (the Swiss analogon of the Nagler 31mm "hand grenade" - and really a surplus of some military optics of the Swiss Army!). With 2.89° TFOV and 27x mag, the Bubble should be within reach; I'll give it a try!

Stephan

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5 hours ago, estwing said:

No,please bore away!...that heavy snow sure does clean the atmosphere Gerry..clear skies 

The snow washed skies leave me speachless Calvin, I literally got lost finding Cass and Cepheus and they were lowish in the sky :icon_eek: lol!

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4 hours ago, Stu said:

I had no idea what the Pleiades bubble was until I found this sketch on Cloudy Nights. Is this what you see Gerry?

Hi Stu, I do see the Bubble some what like this, but this is a very advanced sketch, Mel is one of the best observers there is.

The area presents itself to me with dark "lanes" (not dust lanes) with nebulosity defining them. Another feature is the "outer ring", look at Merope in dark skies and its connected to this nebulosity- this is part of the "bubble". I get more and more out of it every time I obs...

I have been spending hours on this object Stu, and am getting some fine rewards.

PS- I might need years lol!

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I must say that all my obs last night was with a Stellarvue 90mm F7 APO triplet/SW mirror diag/12.25" and piles can be seen in the scope as well as the SW120ED. The more specialized 200mm f3.8 I really wouldn't recommend unless dark skies available and a very keen interest in faint nebula...

This test last night was to refresh my memory for short focal length scopes... I ordered a little 130mm f5 for my grand daughter and want to get her small (I'm ordering) eyepiece collection right. This test really gave me a firm idea of what will work for her.

The real key is the sky Peter.

(and possibly the hundreds of hours I spend on this stuff).

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