John

On 15/07/2021 at 20:02, rob_r said:

Arrived this morning, a new Powermate 2.5x. Will be interesting to see how it compares against my Celestron 2x Barlow on the Moon, Jupiter and Saturn over the coming months. Courtesy of @FLO 

Excellent devices - totally transparent apart from the magnification boost

12 minutes ago, Stu said:

...So often though, the seeing is what makes or breaks a planetary or lunar session, many scopes are capable of giving decent views.

This is very true !

I also think that as much practice as possible develops observational perception and thus a skilled observer can get optimal results from most scope types if they are properly collimated and cooled and the conditions are favourable.

I use all my scopes for planetary observing so 100mm, 102mm, 120mm and 130mm refractors and also my 12 inch dobsonian. I guess the refractors would fall into the small to medium aperture niche that you mention though.

All the refractors give excellent planetary views for their apertures but I guess my favourite is often the ED120 because it has enough aperture to show good amounts of planetary detail while remaining a relatively portable and easy to mount scope. The 100mm (a Takahashi as it happens) gets pretty close to the ED120 though. Closer than the 20mm aperture difference might suggest.

It's been a long time since I owned a mak-cassegrain so I can't really comment on how a 102 or 127 might compare with your refractors but I'd be a little surprised if the mak-cass design didn't do a little better

2 hours ago, Mark at Beaufort said:

Well done Neil I really must try and stay awake. Unfortunately it takes awhile for this galaxy to clear my rooftop.

 

 

Well done indeed Neil

I have a similar problem to Mark - that corner of the square of Pegasus is visible for a while but it's low down at that point and affected by the Bristol light pollution, then it is behind conifers for a good 2-3 hours before being visible again, and better positioned for finding a galaxy of course

It sounds a good SN though - worth some effort

Sounds like you have found your eyepiece "sweet spot"

I have a scope out but cloud is invading the sky here as well.

Probably just as well - I could do with a couple more hours sleep tonight !

Were you using a diagonal with the scope ?

2 hours ago, lunator said:

Hi John,

Paul Couteau used to say that you needed 2x your aperture before you really started doing the right visual double stars 😀

He was speaking about measuring them but there is some truth in it for observing as well. For your 130 a x260 mag is just the beginning 😁

Cheers

Ian

 

Thanks Ian

When I bought my 2mm-4mm Nagler zoom I thought it would only get occasional use but with the Tak 100 and the TMB/LZOS 130 it's often the first eyepiece in the focuser when I'm observing double stars and sometimes the only one I use. I'll be wearing it out at this rate !

Congratulations - a great find !

Mine is serial 8C020 from the same production run

3 hours ago, Voyager 3 said:

At what magnification were you detecting the component John ? Fantastic observations @John and @chiltonstar  .

I went up to 600x but I reckon I was starting to see indications of the secondary component at around 350x. Crazy power for a 130mm aperture really !

I've already had an observing session tonight, reported here, with my 12 inch dobsoninan:

However......... I made the mistake of popping outside to have a quick look before I turned in

Saturn and Jupiter were very much in view, above the local rooflines and saying "come on, look at me"

So out goes the Tak 100 refractor on the Skytee II. No cooling down time with that scope. Straight down to business with the gas giants.

Saturn looked exquisite. The Cassini Division was clear and sharp at 200x. A couple of dusky brown equatorial bands were showing around the creamy disk. A subtle ring shadow was cast onto the southern hemisphere of the planet while the planets disk itself cast a narrow shadow onto the ring system. Beyond the orbit of the rings the moons Iapetus, Titan, Rhea and Dione were glimmering. A view like that could hook a weak person on astronomy I reckon - dangerous stuff ! 

Thence to Jupiter. The giant of our solar system looks excellent. Five cloud belts including the two prominent equatorial ones, adorn the disk. Dusky polar "hoods" over the north and south poles of the planet. The Great Red Spot is hiding around the other side but the view is still excellent. The 4 Galilean Moons laid out as if with a ruler either side of the Jovian disk. Wonderful !!!.

Great stuff - a two part session. And now it's really time to hit the sack !

19 hours ago, Nik271 said:

Well done John! With 130mm the secondary should be touching the primary within the first diff ring, just as you report. I made a simulation with Aberrator

   Ignore the PA in the picture, primary is mag 2, secondary is mag5 at 0.8'

This corresponds well with your observation.

I was not ready last night and forgot my small 'solar' Mak on the mount until late evening by which stage it was to late to cool its big brother.

With only the the small Mak I focused on some 'easy' stuff. Izar, Mizar, Polaris and finally 65 U Ma, which was a first for me. 65 UMa is a nice triple visual system, which actually has 7 components. 

Tonight I'm not making changes, the storage bag with the big Mak is already out of the shed and in the shade 

 

Thanks for this.

My 130mm refractor was, last night, showing a view quite similar to that simulation but with the E / W orientation reversed and a little shimmer in the diffraction rings. So like this:

Possibly about as good as the aperture can do ?

10 minutes ago, Davey-T said:

.... may have a look at SN in NGC7814 shortly as it's easy to spot being in a galaxy.

Dave

Pegasus is behind trees for me currently otherwise I'd be doing just the same

1 hour ago, chiltonstar said:

The seeing here tonight is excellent+, with a stable sharp view at x450 (6 mm Baader Ortho) with the 180 Mak. The secondary seems to be oval shaped tonight and attached to the diffraction ring, but there is at least dark space between the primary and secondary! Better view than I've had before, down to the seeing I suppose. I think I might just claim that as a split........ 

Chris

 

Excellent stuff Chris

I forgot to go back to Dubhe tonight having got rather carried away planetary nebulae hunting in Aquila

Got a few more planetary nebs in Aquila this evening as well as NGC 6781:

NGC 6804

NGC 6803 (small - just 5.5 arc seconds in diameter !)

NGC 6778 (AKA "Son of M76" but actually much less spectacular than the Little Dumbbell which is in turn Dumbbell Junior to M 27 )

NGC 6772 (pretty faint even with UHC filter)

NGC 6751 (quite a nice "puffball" shaped nebula)

NGC 6741 (AKA "the Phantom Streak" nebula, another small one at 7 arc seconds)

Add the better known "Ring", "Dumbbell", "Blinking" and "Cats Eye" nebulae to that and it's been a planetary nebula centered session I'd say

I'm developing a bit of a fondness for observing these little beauties. Lots around and all shapes and sizes

Worth observing them with and without a filter to see which ones show the central star - the filter tends to make that central star much harder to spot.

Just a further note on NGC 6781. I've been taking a look at it with my 12 inch dobsonian this evening. The transparency is not as good as last nights currently and the planetary nebula surprised me by being rather hard to spot with the larger instrument without a filter.

I found it eventually looking rather vague. Adding the UHC filter made a lot of difference though. So I'd advise having a UHC filter fitted while you search for it - it will make it much more disctintive.

This also reminds me that a decent aperture refractor can show DSO's pretty well 

I've got the 12 inch dob out tonight but the seeing seems poor compared to last night. I doubt that I'll get anywhere with Dubhe tonight unless it really settles down a lot.

16 minutes ago, Jiggy 67 said:

@John I take you will be out again tonight. I’m not usually a Summer observer due to work etc but the weather is looking so good I’m gonna be out for the next few nights….as for work…. I retire in 6 months so if I’m late, who cares!! 😀

Yes, I'm thinking of the 12 inch dobsonian tonight.

I retired a while back now - it does help with this hobby !

I had a Tele Vue Gibraltar for a while. It worked well with my 102mm F/6.5 refractor but not so well with scopes with longer tubes. I guess Tele Vue's refractors tend to be on the shorter side so it was designed with those in mind.

Not quite sure that I would liken the stability to the Rock of Gibraltar

I'm sure Olly is correct about the origins of the mounts name though.

4 hours ago, Kon said:

Very nice! Next time I am out I will give the NGC 6781 a try; did it take much magnification or is it better to stay low?

Quite low power will show it - say 50x. 100x - 150x will show the contrast a little better under my skies. A UHC filter makes it stand out noticably more, an O-III filter does as well but on this target I felt the UHC was better.

This one looks like a PN even at 50x, rather than one of those that looks stellar until high power is used.

Great report - lovely night last night !

Lovely night tonight. I'm observing in a T-shirt and shorts

Lots of nice things seen with my 130mm refractor. New to me with this scope tonight was the lovely delicate bubble of planetary nebula NGC 6781 in Aquila sometimes also known as the "Ghost of the Moon". Just about detected without a filter but using a UHC made it pop out nicely. Rather like a smaller version of the Owl Nebula, Messier 97. I'll re-visit this one when I next have my 12 inch dobsonian out.

As well as being dark, the skies seemed steady as well. Silly magnifications as high as 600x were showing up the showcase double stars really well. Can't get enough of Iota Cassiopeia with a fine refractor at high power

Hope others are enjoying the night as well

Here is my new friend, NGC 6781 imaged by Scott Rosen:

Well the seeing is very steady tonight. Zeta Herculis is as clearly split as I've ever seen it, right up to 600x with the 130mm triplet refractor.

Dubhe ? - well, so far, the most I can say is that I think that I can detect a slight brightening / thickening within the 1st diffraction ring at more or less the correct P.A. and right up against the airy disk of the primary star.

Nothing more than that though. I'll wait and try again when it's risen a little higher in the sky.

Zeta Herc is really excellent tonight though. Not as tough as Dubhe of course !

Seems a little odd to be starting at 300x and going up with the 4mm-2mm Nagler zoom but the conditions and the optics seem to be playing ball

The issue for me is that Pegasus does not clear the surrounding houses / trees until the early hours. Can't do a really late one tonight (though it is clear) so I'll hope the SN stays observable for a few days.

I'm 61 and use low power eyepieces with exit pupils of 3.96mm (21mm) and (less often) 5.85mm (31mm) with my F/5.3 12 inch dobsonian. Under my skies (Bortle 5) the smaller exit pupil is generally the more effective one. Both have their uses though.