Dave In Vermont

I don't know how - leave alone why - WD40 got hyped as the 'be-all & fix-all' for everything from cleaning bicycle-chains to arthritis-pains! 10-Points to anyone who can even tell me what 'WD40' even stands for!

Amazing!

It stands for "Water-Displacement - 40th compound tried." Boeing Aircraft wanted something that would displace water from electronics in the controls of jet-aircraft - should the pilot have been a clutz who accidently poured his coffee (or something) into the console of controls for the aircraft. And this compound was chosen because the lubricating-oil in it is "non-persistant" - meaning it will evaporate quickly and not leave much lubricating-oil behind in it's wake!

In non-technical terms = It won't work as an oil for very long as it's designed not to.

Yes - you read that right: It's not supposed to work as an oil or other lubricant.

The next time the genius at the hardware-shop hypes 'WD40' to you - ask him what WD40 actually is and stands for!

I had a similar problem removing the stock visual-back & focuser on my AR5 F9.3 Achromatic-Refractor from Meade. I had to resort to using a 5-pound rubber-mallet! I removed the lens-cell up front first. Then stood the OTA on end with the focuser/VB up top. And went "WUMP!!" around the tube until it slowly could be removed. AgenaAstro in Los Angeles wanted me to film my doing this - long story - and I decided "NO WAY!" I didn't want my smiling face associated with this guy who looks like he's beating the daylights out of an innocent telescope with a HUGE hammer!

I had an equal amount of 'fun' setting the new one Agena got from 'Antares' that also needed a mallet to seat it. But Agena did realize that Antares' new VB wasn't going to work for most people as most people wouldn't be mechanically skilled enough to do what I had to to get that monster on!!

So I have the only AR5 with a certain Antares Visual-Back fitted upon it. I see it's still marked 'OUT OF STOCK' on the Agena website.

Good Luck!

Dave

I use a "Penetrant-Catalyst" called 'PB-Blaster'. And super-hard to remove screws, etc. - are covered in it. Wait an hour or so. Then try again. It's never failed me. Automotive-shops should be able to help you find this, if you have trouble locating it. Or it's sold under a different name over there.

Take your time & don't rush. You'll get it done.

Dave

Yes! It's an old thread from 2015! Which you've raised from the dead - but that's alright. You might consider starting a new one next time if you want a quicker response though.

But I'll do what I usually do and offer you a very good (FREE) satellite-tracker program to see if what you see up there is a listed satellite. The best one for this is called 'Previsat' and is from France (in English). About 60% of satellites are listed by anyone. The rest of them are CLASSIFIED and we're not supposed to know about them (Queue-up the creepy-music here), let alone see them! So here's a link to Previsat:

https://sourceforge.net/projects/previsat/

Just read the instructions and have fun.

Happy Hunting,

Dave

Their mirrors are very good. I have an older GSO 200mm F/4 - and it's excellent.

If I was in the market, I'd buy that Zhumell on-the-spot.

Dave

Mea Culpa - if they are the same critter and are from GSO - then they're even better! GSO over the last couple years has had a serious improvement of their products - both optical and hardware for scopes, etc.

Last Analysis: If I was looking for a large Dob, I'd be on TelescopePlus' doorstep! I hope they're in stock for you. As I said, they usually sell-out pretty quick.

Lucky!

Dave (it even comes with a laser-collimator!)

The Zhumell Dobs are made at the same outfit in China as Skywatcher and various other brand-named ones - like a great many other telescopes out there. In other words - they're very fine instruments. The benefit of the Zhumell one's is they are better outfitted with things you'd likely have to pay extra for after purchase - such as a good 8 X 50mm RACI Finder-Scope (last time I looked). And various other goodies.

Nothing to complain about with the Zhumell named ones. I'm guessing you're finding these at TelescopesPlus, is it? They have the planetary-eyepieces, too by Zhumell. For 1/2 the price as Orion for the same ones.

It's a bargain! And the only complaint I hear is they get bought-out quickly. I don't wonder why!

Dave

TeleVue® makes one of these that works about the same - for 3X the cost of these 'Helio-Pods' - which cost about $15.00 over here (and I like these better, which helps) - but they un-mount super-easy for storage or transporting.

http://www.dynapod.com/dyna-hp1.html

Had a long chat with the inventor/owner. Very nice and smart guy!

Always Triple-Check Your Solar-Filters Before ANY Solar Observing! ALWAYS!

Have (CAREFUL!) Fun,

Dave

As stated: Don't ever get rid of it.

Indeed! I mean - where would you go? When you already have the very finest, the only direction is down!

Enjoy standing on the Zenith,

Dave

10 hours ago, michael8554 said:

Yes Joc, id be a bit wary of a scope with 3 pages of posts.

But flicking through them it seems to break down to collimation, eyepieces, and diagonals, same as any other scope - just an unusual number of opinions?

Michael

The Meade LX-series telecopes have many fans. They can stand for some work when first purchased - or, in the case of buying a used one - checking over to see if a few upgrades are warranted. But all-in-all, Meade LX SCT's are excellent. Which explains their popularity. And explains why I've bought 2 of them - both 12" at that. They're that good.

Enjoy your Meade!

Dave

Buying sets of eyepieces is a common error many beginners make. This as you may find some useful, while others wind-up collecting dust.

Advice: Wait until you have used the scope on various targets to see what you like, and what eyepiece (s) you like and want to go in which direction for magnification.

Last Analysis: Go slowly - for now. Don't buy a set of one type which many of may never be used.

You'll get there with maybe two for now.

Dave

A good website - for all LX-series Meades - is this:

http://www.petersonengineering.com/

Unfortunately, this won't work on 8" LX-series scopes:

http://www.petersonengineering.com/EO.htm

They are available across-the-pond. But I forget who has them there - easy enough to find out though.

Have fun,

Dave

To find the magnification of eyepieces for your telescope, you simply divide the Focal-Length (FL) of the telescope by the FL of the eyepiece. Example:

Let's say your scopes' focal-length is 1,000mm. And you give it an eyepiece of 800mm. - you do this:

1,000mm / 8mm = 125X

I hope this helps!

Dave

That should work fine. As it's branded as 'TS,' it's probably from GSO (Guan Sheng Optics) in China. And GSO makes some very nice optics these days.

It's got a 2" to 1.25" adapter, too - always a good thing to have.

Enjoy!

Dave

It's nice to see people still care about achromatic-refractors! I was thinking I was the only one who still loved them!

Those look & read to be very good scopes at that. I hope the reviews that appear don't just dwell on CA.

Dave

When doing the 'Star-Test' for collimation, a magnitude 2.0 star is suggested. Polaris (alpha-Ursa Minor) is the best choice - as it won't be moving across the sky by much at all. Start with about 200X and slowly increase untill you have a good view of the difraction-rings (circular-lines around the 'donut')

Dave

P.S. When using a screwdriver near your corrector-plate, keep the scope either level or slightly nose-down - this to protect the corrector when you manage to drop the screwdriver.

Diffraction-Rings

Meade always supplys an inexpensive 90° prism-diagonal with the LX90's - has for years. As well as a 26mm Plössl eyepiece. I'd suggest getting a 2" star-diagonal. These will come with a 1.25" adapter so you can use both 2" and 1.25" eyepieces.

Until you've had the scope cooled for about an hour in the outside air, and you've focused outdoors on a distant object/building/etc - I'd not be worried about collimation. It's pretty hard to knock these telescopes out of collimation. Like dropping it down a flight of stairs.

Until you find out what sort of objects 'up there' interest you the most, I'd hold off on any expensive eyepieces - though your scope is quite worthy of top-end ones - and maybe look at some used eyepieces for now. These can be re-sold for about what you pay for them, and they'd help you learn about your preferences.

Have fun -

Dave

Best to align the finder as best as possible prior to using the scope for the alignment with the stars. Then you get the first star in your field-of-view and then dead-center it with the Auto/AudioStar. Now with the tracking of the LX90 engaged - fine-tune your finder. If the stars your handbox chooses aren't visible, you can easily select others. So you're centering the finder, and "training the AutoStar," at the same time.

As my signature reveals, I have a 12" LX90ACF. I had a 12" LX200GPS - but gave it to a professor at my local university who could only afford a 110mm Newtonian Reflector. They pay teachers over here a pittance. I love blowing people's minds!

Pay It Foreward,

Dave

P.S. - "Training the AutoStar," or whatever it's called now, is made clear in the manual that came with these scopes. If you don't have one - let me know and I'll be happy to link you to one to read~download.

When you say your old telescope "made the stars look a little bigger..." - leads me to wonder if you understand how to properly focus a telescope. Stars are properly focused when they appear as the smalled pinpoints of light possible. A telescope won't make stars look bigger - but brighter. Stars are much to far away to magnify regards size.

There's a long thread here you may find quite illuminating <koff!>:

Don't worry - we'll help get you and your telescope works together!

Dave

One things that I've noticed, based on the reports from many other people and my personal experiences: When Skywatcher was told about such issues as the poor focusers, endemic to Maksutovs a few years ago, with resulting mirror-flop, they listened. Soon after the SW focusers were buttery-smooth and mirror-flop/slop had vanished! Note the picture of my 150mm above? I "upgraded" it with a 10:1 Crayford focuser. But I needn't have bothered - mine arrived with the new focuser and it didn't need the assist!

Another former issue was the non-standard size of the threads on the visual-backs, making an adapter necessary to add various components. SW heard the concerns and that problem vanished too!

Skywatcher is an outfit that listens, and acts, on the customers' desires & concerns. With Synta quite willing to customize to Skywatcher's specifications.

Top that!

Dave - who doesn't own stock in SW or Synta (yet! )

SW Maks are made by Synta, as are Orion, Celestron, and another one or two. And they are excellent! They hold collimation like a champion. Very strong construction. And excellent optics and peripherals.

I have their 150mm F12 Black-Diamond Maksutov. I'm thrilled with it! And very glad I added it to my fleet.

Have fun -

Dave

It appears this article & thread has been here since 2009. Very cool it's still going on! So I've taken it upon myself to put the original in a Pdf. format so it's will be easier to read at leisure. Here we go:

Primer -Understanding Night Vision, Averted Gaze and Telescope - Tapping.pdf

And a special filter for seeing things like a Black Hole, etc.

Hope you like it!

Enjoy -

Dave

Astro_Baby's collimation-guide shows the off-set in fast Newtonians. Most instruction-guide do not - serving to compound people's confusion. Here's a copy of her guide to tuck-away for safe-keeping:

Astro Baby's Collimation Guide.pdf

Enjoy! Collimation becomes like riding a bicycle - the first-time can be a pain. Then it becomes simple.

Dave

Well - Thank you! I'll use it until it explodes, and keep the extant Pdf. on file regardless.

Good find!

Dave

Ah! It works!

Is this link going to stay up & running? Thank you - regardless. It fits the bill.

Dave

One of the best guides to collimation is written by a member here - Astro_Baby. Unfortunately her website is out-of-service. Otherwise I'd toss a link - it has an excellent illustration of the offset commonly found in fast-Newtonians (F5, F4, etc.). It's just a flat-out great guide for us owners of Newtonians, and passing out freely too.

As her site is dead, here's a copy from my collection:

Astro Baby's Collimation Guide.pdf

Please let me know if you have any problem with the above link? Thanks!

Hang onto the pdf. -

Dave