John

1 hour ago, Highburymark said:

I’ve had various set ups - a Quark which was poor, two Lunts which were great double stacked but both (one in particular) underwhelming single stacked. A couple of Baader/Solar Spectrum Sundancers which were basically nice etalons, but with other (significant) problems, and a double stacked Solarscope 70mm, which is wonderful - though once again, nothing particularly special single stacked. I’ve learned enough to show that all brands are highly variable in both quality and bandwidth, but Quarks/Solar Scouts and Coronado are more variable than the others - a view backed up by specialist forums like Solarchat. But these are mostly cheaper, entry level products. Interestingly, the real Rolls-Royce etalons were produced many years ago by Solarscope and pre-Meade Coronado. Though if you dig into the history of commercial solar Ha filters, all four brands share a common ancestry. 
One thing’s for certain - Stu’s route is a very cost effective route to wide-aperture observing. But the Beast will require good seeing to really shine!

I have to say that this variable performance is what has put me off H-Alpha in the past. The Lunt 50 (single stack) that I had was a so-so performer as was the PST that I owned for a while. We have 2 PST's in my society one of which is not bad but the other rather unimpressive. I have read a lot of reports of poor Quark performance. 

I realise that what such equipment is doing is pretty complex and that there are more satisfied owners out there than unsatisfied ones but it is still difficult for someone who is a little ambivalent about solar observing to feel motivated to spend several hundred £'s on what seems to be a sort of performance "lottery" 🤔

@Stu's approach with "the beast" makes a lot of sense though - have it put together and sorted by somebody who knows what they are doing and knows good H-Alpha performance when they see it 🙂

I'm glad that their eyepieces are better than their surveys ! 😁

I have looked through a number of H-Alpha scopes (up to 100mm) and even owned a couple but, somehow, the interest didn't hold with me.

But, those experiences were during the "quiet" part of the solar cycle so perhaps H-Alpha activity was quiet as well.

I do white light observing (herschel wedge) from time to time, mostly at society outreach events.

The Sun is a very interesting target because a) we depend on it, b) it changes all the time, and in real time and c) because it can be a nice, comfortable experience observing it 😁

So, speaking for myself, I would not rule out taking more interest in solar observing and I will be following @Stu's experiences with "The Beast" with interest 🙂

The seeing here is still poor so that plus the blustery wind and the chill have persuaded me to pack the scope in. No point in doing it if it's not enjoyable 🙄

It's good to see that some folks are having better conditions and some good observing though 🙂

5 minutes ago, ObscuredView said:

Where do I find the classifieds once I qualify?

Here is a link to that section of the forum:

For Sale / Swap (UK) - Stargazers Lounge

I've caught the end of Io's shadow transit. Rather poor seeing here though and very blustery despite the clear sky. Funny how it varies around the country. Wind chill a real factor this evening. 

I'll leave the scope out but might not feel that tempted to join it for long 😬

21 minutes ago, Ags said:

Good info, thanks! What's the diameter of that circle?

The whole field is around 12 arc minutes in diameter (1/5th of a degree approx) and the red circles are around 15-20 arc seconds in diameter I would estimate. The current separation between Sirius A (the centre of that mass of light) and Sirius B is around 11 arc seconds. These are rough figures of course !

14 minutes ago, Ags said:

Tried tonight with my Long Perng 90... it's not the scope for the job. I'll try again with my C6 on another night. Jupiter was very soft tonight - last night's superb seeing was not repeated.

You do need a night of pretty good and steady seeing.

I tried it a few nights back with my ED120. I've seen it quite a few times with that scope but it was not quite possible on that occasion. There are two faint stars in particular that I find need to be visible for a sighting of Sirius B to be possible. I have circled them in red in this refractor view sketch. They are around mag 11 or so I reckon but hard to see because of the brightness of Sirius A. I could barely see one of them a few nights back so I was not surprised when the Pup star did not show itself.

11 minutes ago, Stu said:

I weighed the scope today, and it came in at 13.65kg fully loaded with rings, dovetail, binoviewer and eyepieces. Surprisingly light I think. It is around 1.5m long however, so is quite demanding on the mount.

Years ago, I bought a car wheel bearing, plus some other heavy duty bearings and intended to build a mount from it. I suspect that if the scope is supported both sides in the style of a Panther TTS or Peter’s home made variant then the vibrations would be reduced for such a long scope. Anyway, that’s a project for another day. I’ve just built myself a decent workbench finally so I’ll be able to do some proper DIY stuff now, rather than the wood butchery I’ve done to date 🤣.

That is quite light for a 6 inch F/10. My Istar 6 inch F/12 weighed around 17kg I seem to recall. Such things are challenging to mount in a way that allows the full capability to be realised. I'm sure you will find a way though - it's got to be worth a little effort 👍

Wow !!!

Things are really moving on now, aren't they 😲

10 minutes ago, lunator said:

Cracking night tonight. Nothing like a cold blast to give decent seeing and transparency. Observed a few more doubles including one very tight pair, also saw a few new faint fuzzies just defrosting a bit at the mo. 

Cheers

Ian

Glad it's clear in South Somerset. It's rather cloudy here in North Somerset with only one or two stars peeking through from time to time. A bit disappointing after last night 🤨

Glad you are having a good one though, Ian 🙂

I'm waiting for Orion Optics customer feedback survey 😁

It will be interesting to see if designs change as a result of this. I have completed it as well.

In the past Al Nagler has not been keen to remove undercuts when asked the question but I believe that he is at least partially retired now so his son and others may have more influence.

I have to confess that I don't find undercuts a particular problem but for the sake of others I did say in the survey that they should be re-considered.

Removing the finder, racking in the focuser and separating the tube from the mount are the usual steps for transporting a solid tube dobsonian by vehicle. It is also the one time that I used the collimation locking screws as well.

The collimation will almost certainly need re-adjustment before use at the other end of the journey though. Hopefully it will not be too far off if the locking screws have done their job. No need to over-tighten these screws though - Orion Optics used to have a sticker on theirs that said "finger tight only".

The clouds have cleared away here so I have managed a bonus view of Jupiter just before it dipped below the roofline of our house.

Ganymede was just starting to exit the jovian planetary disk so there was a slight "bump" on the western limb but otherwise I was presented with the unfamiliar sight of Jupiter sporting just the one Galilean moon (Callisto) with Io having moved behind it's parent planet.

Europa was well in transit and not visible to me against Jupiter's disk.

Looking at some of Orion's binary stars, the seeing seems to have gone downhill somewhat so I doubt that Sirius B will b "on" tonight. I might give it a try anyway though 🙄 

Clouds have now intervened with the observing, annoyingly.

I got as far as Europa just starting it's transit and still visible against Jupiter's limb, as is often the case with such events. My guess is that Europa will quickly become very tricky to see against Jupiter's surface as it moves across the disk.

Ganymede was visible as a bright spot for at least 50% of it's transit but has now become very tricky to see. 

I suppose the moon's illumination by the sun can vary slightly as it moves in it's orbit and the angle of solar illumination, relative to our vantage point changes. It may also be (likely, really) that Jupiter's south polar region is not an even albedo across the diameter of the planet so the visibility of a transiting moon against it will change as the transit progresses.

All interesting stuff and very enjoyable to watch. One effect that was noticeable to me tonight was shortly after Ganymede started it's transit and while clearly visible against Jupiter's southern cloud tops was that both the moon and Jupiter seemed to "pop" into 3D. They both looked like the spherical objects they are with one in orbit around the other. The solar system in action in real time 😁

13 minutes ago, Stu said:

Good stuff, cloudy here 😞

So, is Ganymede appearing bright or dark against the surface? Probably bright just to prove I was talking twaddle all along 🤣

It's bright currently (sorry Stu !). Brighter than the background cloud tops. It's transit is across Jupiter's far southern polar zone though, which is a bit darker than the STZ to the north of it. Europa is going to start it's transit at 22:02 but further north so it will be interesting to see how that appears.

1 hour ago, Stu said:

🤞🤞🤞

Still lovely here - very good views as Ganymede starts it's transit 🙂

54 minutes ago, Stu said:

There’s a fairly uncommon Ganymede transit coming up which I posted about a while ago. In theory Ganymede is a bit darker than Io or Europa so may show as dark against Jupiter and so be visible more easily during its transit. Cloudy here inevitably 🤬

It's still nice and clear here but will it last ???? 😬

36 minutes ago, John said:

I'm just watching the GRS transit with my 100mm refractor. The GRS is nicely defined although it's colour seems a little muted this evening. The seeing here is also quite decent so 150x-180x proving useful.

 

The 100mm is delivering good views. So good, that I was moved to try a sketch, which I don't often do:

I'm just watching the GRS transit with my 100mm refractor. The GRS is nicely defined although it's colour seems a little muted this evening. The seeing here is also quite decent so 150x-180x proving useful.

8 minutes ago, Captain Scarlet said:

It is very cool to easily see dust lanes in M31 with the 12”. And some deep-sky objects within M31 are also possible, such as globular clusters, though you need experience and patience to get those (I haven’t got any yet). Its satellite galaxies are also quite bright, M32 and M110.

Magnus

I never found the dust lanes too obvious with my 12 inch. I see them more clearly with my 4 inch F/6.5 refractor and the 31mm Nagler under a really dark sky - 3.8 degree true field 😁

I agree with @Stu, Messier 31 looks better with a smaller, wider angle instrument or even large binoculars. 

When I had my 12 inch dob I spent many happy hours searching out smaller galaxies and galaxy groups though. 

Andromeda (the constellation) looks great with the naked eye of course 😉

The low altitude that Sirius reaches in the UK certainly does not help this challenge. I guess that from parts of the world where Sirius rides high in the sky, spotting the Pup is somewhat easier !

They probably wonder what the fuss is about 🙄

Jupiter's disk features do not respond well to the very high magnifications that can be used on Saurn and the Moon, for example.

Generally I've found 130x-160x has delivered the best contrast on the giant planet on nights when 200x plus has been good for Saturn or the Moon.

So "throttling back" the power is often a good approach 🙂