Jiggy 67

It’s the only solution really. I leave mine uncovered until it’s clear, overnight if necessary. You could quicken it up with a hairdryer if you want, just don’t wipe it.  

Good shout 👍

37 minutes ago, Physopto said:

So hope it improves over the next month and a half!

……Have Faith

Great report Joe, it’s been driving me mad trying to identify the star you saw, had the charts out and everything!!….could it be the one in the first image? HR7759? Which is a red dwarf and a double as well. As for the cluster, the only recognized one I can see nearby on SkySafari and Interstellarum is NGC 6910…..is that a possibility?? The images below are Northern Hemisphere…..it’s a real headache trying to picture a Newtonian in the Southern Hemisphere 😂
 

I’m not sure such a list exists. Basically observing any emission nebula can be assisted by using an OIII or H-beta ( much less so). These nebulae contain a lot of hydrogen and oxygen whose atoms are being excited by nearby radiation into emitting light in the oxygen and hydrogen part of the spectrum, planetary nebulae are a perfect example of this phenomenon so these filters can help by blocking out other wavelengths. But that is not always the case and it can be very personal, what works for some may not work for others. A UHC filter does the same but over a wider part of the spectrum so is more versatile but again it is personal choice, a list of objects is probably impossible.

A list of objects would be a bit pointless in my view, I would observe any emission nebulae and try out your own combinations to see if they assist…..Of course, others may disagree 

Tuesday 7th September with a New moon and a very warm and clear evening was setup beautifully to be my first proper session of the new season so I set the EQ6-R-Pro up after it was put away for most of the summer (this nightmare reminded me of why I leave this setup outside throughout the winter!!) and mounted the 8inch reflector.

It was a lovely evening but I have a wooded area directly to the West with high trees, still in full leaf which restricts my view and a rose bush over an archway into the garden which really got me down because Saturn and jupiter pass through it........I might just have to do something about that! 🪓

So I started with some easy objects, just to get my eye in again after the break.

NGC6885 and 6882. Two lovely and large open clusters almost merging into one. NGC6885 centred around a bright star, 20 Vul, and containing approx 30+ stars, although there are clearly more part of this cluster. NGC6882 is below and to the left of 6885 (inverted view) with slightly fewer stars but three very bright ones including 19 Vul. Very nice pair of clusters through the TV Panoptic 24mm (x41 mag)

NGC7243 is a large open cluster in a rich star field containing 50+ stars. Started on this one with the TV 24mm (x41 mag) but it was also very nice with a bit of magnification, the 9mm Morpheus gave me x111 mag. There is a nice double star in this cluster, Struve 2890, which is easily split as two evenly matched white stars. The Morpheus 6.5mm gave me x153 mag and a nice split of the double with one star at 1 o'clock to the other.

I kept trying for Jupiter and Saturn which should have been nicely viewable by now........Damn that archway!!!

Next was globular cluster, M72. I have to say I'm not sure I got this. I think I found it with the Morpheus 17.5mm (x57 mag) but it was very faint and small, almost stellar in appearance but something made me think it wasn't a star. I tried the 12.5mm (x80 mag) and the 6.5mm Morpheus (x153 mag) but it remained very small and faint. There was an appearance of nebulosity around it, possibly the crowd of stars around the core but if it was the glob, I could only see the core.

Finally....Saturn appeared from behind the bush and it was worth the wait!!......stunning as always. With the 9mm Morpheus (x111 mag) it appeared nice and bright with the rings at quite a shallow angle, maybe the reason I couldn't make out the Cassini Division. The seeing wasn't really allowing me to see much banding on the planet either but what I did enjoy viewing was a clear dark gap in the rings in the bottom right hand corner of the planet as the planet itself cast a shadow on the rings. Phoebe (i think) was also clearly visible.

Jupiter was toying with me, I could see it through the bush but the view was awful......I would have to stay up a lot later for it to clear the bush...not really do-able on a school night....I'll catch it another time.

I ended the night with globular cluster NGC6934. Easily found with the 17.5mm (x57 mag). It was quite faint but, also, quite large appearing as a cloud of non-resolvable stars. I tried a number of focal lengths down to the Morpheus 4.5mm (x222 mag) where I began to see the hint of stars resolving, mainly with averted vision but they were definitely separating into individual stars at the edges. A nice, large and reasonably bright cluster which would benefit from eyepieces with good contrast.

Overall a very good start to the season

1 hour ago, Physopto said:

It is always possible for one of us to guide you and your car in or out whilst following a red light though.

That sounds like potentially  a laugh 😂 🤣

You can’t polar align using the view through the telescope, eyepiece or camera, not using your app anyway, but there are other methods.

If you’re using an equatorial mount, it’s the RA axis that you are aligning with the North Celestial Pole, in which case, the app requires a polar scope 

2 minutes ago, discardedastro said:

I have a big VX16 Dob I happily look through with my Mk. 1 eyeballs, dodgy as they are.

This mount hosts a modest little 200mm Newt and a camera imaging at 0.5"/px for very high resolution galaxy imaging. For what I do the difference between mount performance of 1-2 arcseconds and 3-4 arcseconds of error is the difference between a superb image and a dissatisfying result.

Without all this faff I produced the below and a dozen other images I am very happy with.

Is any of this necessary? Well, no, probably not. Will it extend the life of this expensive bit of equipment? Certainly. Will it reduce the amount of time I spend swearing at my mount at 1AM when the tracking isn't quite perfect? Possibly. Will it improve the performance of my mount? Probably. Will I enjoy doing this, regardless of any of that? Absolutely!

For me, astrophotography is as much about the optomechanics, sensors, optics, and precision engineering as it is about the stars, galaxies, and nebulae that I get to image. I take great pleasure in knowing that mechanically, everything is sound, working well, and doing what I want, and that I am able to achieve such precision in my back garden. The skies above aren't the only thing we can marvel at - modern engineering and precision brings some of us joy, too.

You may as well ask a classic car enthusiast if it's really necessary to rebuild their car's engine or replace some rusty panels!

Good response, fair enough, crack on 👍👍

23 hours ago, discardedastro said:

Personally I find videos can be helpful in parts but nothing beats carefully taken photos and text. Having said that I'll try and film some bits of the reassembly and do a bit of a video about it all - I'm short a video camera but phones work pretty well and I might be able to borrow work's proper camera for a few days.

Bearings arrive tomorrow along with some of the missing tools - I have some things to do at the weekend but will try and make some progress on Sunday. The main nut (smooth) on RA Is an absolute nightmare so far - a chain-style oil filter remover has done nothing but marr the surface (even with some amalgamating tape to protect/grip) so am hoping a rubber version of the same tool will do the trick. I suspect Skywatcher have a specific tool that engages with the recesses on the back like a giant pair of circlip pliers!

I've got both EP and regular bearing-grade lithium grease on the way. I would say that generally the grease I've found so far is looking like decent lithium stuff. Not the notorious Synta Tar. Shims and replacement Teflon washers I'm just trying to find a good source of now - given the (theoretical) simplicity of the "hypertuning" of the worm gear alignment, i.e. make a few accurate measurements and shim accordingly, seems a no-brainer to do it while I've got it all open.

I am giving a bit of thought to what I might need to do to properly tune the alignment later on. Current-based measurement of motor load seems a sensible easy "precision" method beyond sticking an ear on it while adjusting worm gear offsets, belt tension etc. I've got a fairly accurate bench power supply handy (Rohde & Schwarz NGE100B - marginal but can do 6A in parallel mode) as well as a R&S Scope Rider with precision ammeter clamp probes, both borrowed from work, so I think I'll give that a go! I've also been giving some thought to vibration measurement; back in my drone engineering days we used to do FFT analysis of accelerometer data which would pretty readily show peaks at resonant frequencies relating to e.g. improperly balanced props, or damage in bearings. I have a few precise MEMS accelerometers handy so I figure it wouldn't hurt to just try doing some measurements with that and see if anything interesting falls out.

I’m sorry…..but really????…Can’t anyone just be happy looking through a scope anymore on a reasonable mount. I don’t mean to offend but is any of the above necessary??

……..It’s neck and neck!!  Nothing to split between the UHC and 0III !!…….🤣😀

3 hours ago, John said:

Just on the filters, I was happy with just an O-III (Astronomik) for a couple of years with my 12 inch dob. I have now also added a good UHC filter but the O-III gets much more use and has noticably more "oomph" especially on targets such as the Veil Nebula which is an absolute "must see" with a good sized dobsonian. 

You’re absolutely right John, I’m not saying don’t get an OIII, I definitely would, but I think a UHC is a better introduction to filters. I think if I had started with an OIII I would have been turned off filters for life because it really does need a bit of aperture. I think a UHC is a good way of introducing yourself to narrowband filters 

I can see where @Louis D is coming from with the filters but I disagree (as we all do sometimes 😀) The UHC has a wider band pass and so let’s in more light across the spectrum which means it’s better for a wider range of nebulae, I would get an Astronomik UHC first followed by the Astronomik OIII next. The OIII is a narrower band pass and more specialized to the oxygen end of the spectrum. It can dim your target significantly, though you will have the aperture to compensate for that to some extent 

Thinking about it, Either would be ok as you must already be using a 1.25 adapter in your focuser to take 1.25 ep’s

A 2 inch otherwise you would need some sort of adapter, it’s the focuser that you’re aligning the secondary with

Before looking at the software, there are three mechanical issues to check and rule out:

It helps if your PA is as accurate as possible. Many will disagree with this but I have been using Synscan and EQ6 R Pro for a few years and I am 100% certain it makes for more accurate pointing 

An accurate home position is crucial. There are videos to assist with this.

Use alignment stars on the same side of the meridian as your targets. If you Star align on one side of the meridian and then slew to a target on the other side, you may suffer from cone error which skews the pointing accuracy. If you do suffer from cone error, you can compensate for this with a three star alignment, the third star being on the opposite side of the meridian from your first two……This is actually the only purpose of a three star alignment, the third star has no other purpose other than to compensate for cone error 

Lovely sketches......as always. Trumpler 1 appears to contain a few double stars, are they genuine or just line of sight??

Well done, you should be very proud......but don't ever try to sell me a car!!

I agree, keep sand away at all costs but other than that I wouldn’t worry short term

How about using imaging for visual observing??….maybe this is the way forward??……

https://unistellaroptics.com

28 minutes ago, Voyager 3 said:

@Jiggy 67 I agree , but all features in SkySafari pro is not available in the free version . For example , one can't add eyepiece circle by adding equipment (s) . Also one can't measure the distance between two objects in the free version . Making observation list is also not possible . And as said , the database is HUGE compared to the free version and you can even download the Gala extension to add other objects down to 18th mag . 

I upgraded from the free version and I find the Pro version absolutely worth it . But if you are a beginner , the free version is more than enough for a great start . 

You are absolutely right, I have the pro version on the Mac and plus on the phone, I think I meant, in terms of the planetarium and how it’s updated or not updated , which is what the OP was asking, it’s the same program 

I’ll do my best but others please chip in

1 - SkySafari is completely up to date, it’s software based on mathematical science that runs constantly, it can’t be “out of date” as far as I’m aware, in fact, you can pick a date a thousand years in the future and the starchart for that date will be absolutely accurate. Many binary stars are actually many AU’s apart and so take many many years to orbit each other, some hundreds of years, therefore any movement of many of them will be indistinguishable to the likes of us. Even then, the program will follow it

2 - Not sure about this, but I imagine you have got to think in 3D with an up, down and all sides sideways. The angle and separation will be correct, but you have to consider perspective when it comes to angles in space

3 - No, the program is the same, there are just more objects in Pro

HTH

2 hours ago, wookie1965 said:

Hi when you say seeing and transparency where do you get those numbers from please.  I think they are on the Clear outside app but if you have another resource that would be most helpful thanks.

Paul

If you have SkySafari, when you create an observation (to record an observation of an object) there is a drop down menu for recording the seeing. 

Excellent report as always Joe......I'm impressed that you can get to x686 magnification, you must have really steady skies at the moment. M57 really is a wonderful object, I've read some recent research on it that explains that we are looking at it from an angle which causes us to look straight into the cone of the nebula, sort of like looking down a pipe. If we were to look at it from the side we would see an elongated cloud......stroke of luck for us really 😀

The Baader Contrast Booster is good as well, brings out the banding in the planet