Asking for advice on optimizing my new kit

[Tiago]

So, finally I had first light on my new Orion 120mm f/5 refractor. Astroshop dropped the ball epically on this one, sending me the telescope without star diagonal, eyepieces ad RDF. Even after promising me they'd send the parts the next day, it took them three days and a few phonecalls to ship them and then a further 5 for the parts to arrive to me. Despite getting two used eyepieces instead of new ones (some fringing on the rubber cups, and fingerprints everywhere), the quality is ok for the 10mm (to be expected) and actually pretty good for the 25mm, so I'm happy to have the scope together, to have confirmed the OTAs optic quality and to be done with them and their business.

Anyway, a couple of hours outside with the little beast mounted on the AZ4 brought me some nice views of M81, M82, M51, M42, M45, NGC 884 & NGC 869, M103, M34 and M41, plus a couple of meteors while looking at them. The Pleiades and the Double Cluster were awesome sights, just what this scope is all about, and M42 showed some detail in averted vision, not just a large, fuzzy blob. If only it had arrived last week, I'd have pitch black skies - yesterday I had to deal with background light and some light pollution, but the good old Milky Way could still be seen with the naked eye, albeit just barely.

The AZ4 is rock solid, even with the aluminum legs extended, and the scope balances nicely on it.

So, to the issues I'm asking for advice on:

Focuser:

The 2" focuser is so stiff it seems to be suffering from a permanent case of rigor mortis. It's so stiff that while focusing, it gets objects away from the FOV at high magnifications. Webcam imaging was impossible in this condition. I assume it will become better with use, but will I see a decent enough improvement by removing that gunk they lubricate it with and replace it with a proper lubricant?

The AZ4 Mount:

Same thing, really. It's a bit to stiff to start moving, particularly in azimuth (it's not the tension, even when loose it offers some initial resistance), so that makes things a bit harder when trying to image with the webcam and a 2x Barlow. Again, I assume it will become better with use, as I really don't want to pry it open.

The Barlow:

Well, I now have two of those - a Celestron Omni I already had, and a Skywatcher 2x. Don't see much difference in them, and they do seem to lose a fair of detail when blowing up the image. Is it worth going for a good 3x Barlow and a better 10mm-ish EP to make my life easier with planets? I can see Saturn fine (a bit small at 120x but fine) however Jupiter is just too damn bright to see any detail on it - just a large, focused white blob of light with the moons going around it, also focused. Again, advice is appreciated in order to improve the experience.

Also, the CA, while present, is nowhere near as bad as I was told it would be - it's noticeable on brighter stars (especially those whitish/blueish in color) such as Sirius and Rigel, apparently absent from Betelgeuse and Aldebaran, very slight on Saturn, and noticeably present but not intrusive on Jupiter at 120x. Stopping down the scope gets rid of it, but then again, it becomes a larger, heavier and more expensive 50-60 mm refractor, which kind of defeats its purpose.

All in all - pretty satisfied, would really love to get rid of these minor annoyances - please chime in and share the wisdom

[nephilim]

Although I cant help with 1 & 2, I can say that my Skywatcher 2xBarlow is so good iv taken the lense out & now use it as an extension for web camming I bought the 2.5x Revelation & its a great improvement for little outlay. My 10mm supplied with my 130m was naff also so I replaced that with a Meade 5000 HD-60 9mm(Excellent optics but pricey at £86) I've heard the 8mm BST is a good ep at a good price although barlowing that might be too much for the scope, but then again your seeing in Portugal will be far better than in 'can never see stars anyway' cloudy uk.

Steve

[Tiago]

Thanks for the input. The 10mm is decent on it's own, but when barlowed it is pretty bad - it might be the EP or the Barlow, or both, who knows. Anyway, I'd rather spend €100 on an eyepiece I'll be keeping than on a polished [removed word], and hence the asking for advice.

[Moonshane]

letting the scope cool / warm up will provide better images of Jupiter - contrary to what people might say, my own experience suggests larger fracs require a period of equalisation to provide best results. a baader neodymium filter or light pollution filter will also pull out more detail but in truth I feel a 120mm f5 achro is not a good scope for planetary observing at high power. a 150mm f5 newt would be far superior.

your scope is a great wide field instrument though.

re the focuser, try loosening off the lock thumscrew underneath or alternatively, there are (I think) some small grub screws in the focuser body (on the top side) which might need tweaking a bit. with some adjustment, you should get this quite smooth (I presume it's a rack and pinion focuser?). yes, I found that removing the hard grease and redoing with white lithium grease helped on the one I had a while back but in the end I replaced it with a dual speed crayford (I had the f8.3 Celestron version).

cannot help with the mount as I only use dobs and have not used this one. I cannot imaging it's well suited to imaging though, especially at high powers.

hope you enjoy the scope and get the minor things sorted.

cheers

Shane

[Tiago]

Thanks Moonshane - I'm not that big on planetary, as I bought this scope for other purposes, but it would be nice to be able to see them decently. But money is better spent enhancing the strong points on this one, and probably wide FOV EPs and filters are better choices.

Also, thanks for the tip on the focuser, I'll take a look (it is indeed a R&P). As for cooling down, it does take a few minutes to stabilize, then it is pretty good.

The mount is awesome, very very easy to use, and decent enough for webcam at moderate powers (mostly because the objects move out of the FOV really fast). It might be stuck from being new, or stuck from being lubricated with mud, who knows... :/

[Moonshane]

Newness definitely = stickiness sometimes. Good luck with the scope; it's certainly a very capable instrument.

[Moonshane]

ps I should stress that I am completely biased towards newtonians for their excellent aperture per penny, their true lack of false colour and their sharp detail when collimated, as well as the ease of use with dobsonians. I can track doubles at 400-500x in orthoscopics easily with my dobs. I'm sure your mount will smooth off.

[Tiago]

ps I should stress that I am completely biased towards newtonians for their excellent aperture per penny, their true lack of false colour and their sharp detail when collimated, as well as the ease of use with dobsonians. I can track doubles at 400-500x in orthoscopics easily with my dobs. I'm sure your mount will smooth off.

I know, and I almost pulled the trigger on a 2nd hand, 10" dob. Then practicality entered into account, and the kind of terrain/garden/house I have, plus two over enthusiastic dogs, multiplied by my own innate clumsiness would probably not yeld a great result. I may still get one one day, who knows.

[Moonshane]

sounds like you made a good choice