131 replies to this topic

[alphatripleplus]

No glitch. The link - and the site - work just fine.

Yeah, now it is working again for me. (Earlier I got a message that the page did not exist).

[Red Giant]

What objects specifically are good to observe with this telescope, and what size eyepieces would you typically use?

[Kim K]

I had an original ST80, but sold it ...to my everlasting regret. I remember looking at Jupiter was an explosion of color, but with a #58 green filter all CA disappeared and the eq bands were distinct. The image was green, but what a transformation.

[Tom Stock]

Probably need to give them a call. I ordered my xt10i in late May/early June and got it the first week of July.

Who did you order from? I ordered from Highpoint Scientific.  I'm getting very close to cancelling that order I double checked and my order was placed May 2... they are estimating mid Nov ship date (yeah right!)

Edited by Tom Stock, 05 November 2020 - 11:39 PM.

[BFaucett]

Just received an email from Orion. The good old Short Tube 80 in 4 different offerings is again available. Here is the link (I hope it’s not a violation of the rules here): https://www.telescop..._cPFYvjhphYavUw

I’m in no way affiliated with Orion.

 

BTW, here's the desktop / laptop version of the link (instead of the mobile device version of the web page):

 

https://www.telescop..._cPFYvjhphYavUw

 

Cheers! Bob F. 

Edited by BFaucett, 06 November 2020 - 04:28 AM.

[BFaucett]

What objects specifically are good to observe with this telescope, and what size eyepieces would you typically use?

 

You may find these links to be of interest:

 

The Mother of All Chinese Scopes

May 31, 2009

by Rod Mollise

http://uncle-rods.bl...ese-scopes.html

 

The ShortTube 80 Telescope: A User's Guide

(The Patrick Moore Practical Astronomy Series) 1st Edition

by Neil T. English

Publication date : September 14, 2019

https://smile.amazon...uct/B07XM1YNVM/

(Use the "Look inside" feature to read the first two chapters.) 

 

Cheers! Bob F. 

[Jon Isaacs]

What objects specifically are good to observe with this telescope, and what size eyepieces would you typically use?

 

The strength of the ST-80 is that it is compact, rugged and can provide nearly a 4.0 degree field of view using 1.25 inch eyepieces. It's relatively lightweight at 3 pounds so it can be mounted on a photo tripod.  

 

It is a good low power, wide field scope, the Pleiades are wonderful, the California nebula with an H-Beta filter. It can be used for double stars and the planets but a good 80mm F/11 achromat or a 80mm ED will do significantly better.  Pretty decent on the moon. 

 

They're competent as a terrestrial scope and the CA disappears during the day if you only remove the small (42mm) center lens cover.  This transforms them into a 42mm F/9.5.  It's also effective viewing the phase of Venus. 

 

I think of them as half-binocular, half telescope.

 

For $100 or so, they're tough to beat and they make a good travel scope since the investment is small.  I buy them used and then give them to beginners and no so beginners in need a decent telescope.  

 

My current ST-80 is an older Celestron First Scope EQ.  It's different than any other ST-80 I have ever seen including other FirstScope 80 EQ's, it has a threaded on metal objective cell, others are plastic, and a metal threaded on dew shield.  It's a keeper.

 

This the iOptron version of the ST-80.  It had a horrible plastic focuser which I replaced with a metal focuser before I gave it to someone. 

 

 

This is the Firstscope 80 EQ before i put a 2 inch focuser on it.  I have the mount configured as an ALT-AZ mount.

 

 

Jon

 

[Tom Stock]

I picked up an Explore Scientific Nano for my ST-80 and it's the perfect size.

 

I also purchased an RA drive expecting to want tracking but at the low powers I use this scope at it's completely unnecessary.  I didn't even bother with it.

 

I removed the dumb flex cables because they are just in the way and found most of my vibration came from them.  Installed aluminum guitar knobs instead with one on each side for RA.  It's the perfect mount for this little scope.

[Mitchell M.]

Who did you order from? I ordered from Highpoint Scientific. 

I placed my order on Amazon so I could get a discount on future order. Ships from Orion Telescopes & Binocular.

 

Eta, quick lookieloo, not finding the xt10i on amazon. 

Edited by Mitchell M., 06 November 2020 - 03:12 PM.

[John Fitzgerald]

If you buy something from Orion, plan on keeping it.  Their replacement parts sale policy (to original owner only), causes deep discounting for resales for a lot of things that have parts that are subject to wear and tear.

[JIMZ7]

That's cool. Had the ST80 & ST90 but sold them both. Swore I was out of astronomy since my first scope in 1957. Had 37 scopes Should I buy another? Getting that fever again.

Jim

[CHASLX200]

That's cool. Had the ST80 & ST90 but sold them both. Swore I was out of astronomy since my first scope in 1957. Had 37 scopes Should I buy another? Getting that fever again.

Jim

Always buy more is my motto. I had a ST90 version as well. I liked it better than the 80. 

[JIMZ7]

Always buy more is my motto. I had a ST90 version as well. I liked it better than the 80. 

Having both scopes I didn't feel there was a big difference. On the Orion ST90 I didn't like the long focuser. It made the scope look more like the Orion ST80. Should have kept the Orion 100mm f/6 refractor. With 2" eyepieces made the views a "wow" event.

Jim

[jcj380]

Omegon sells (or did sell) an ST90.

[JimFR]

I had mine out last night.  It’s old enough to have kids in school but I keep it nicely wrapped up and take care of it.  Here in Toronto, we had some exceptionally clear skies last night, and with Orion up early as the winter skies move in, I did some bopping around with it on a photo tripod.  It becomes my winter scope that I can just pop out at a moments notice for a view and pop back in.

[ItsMeTony]

  I have the Meade Infinity 80.  I believe it's the same as the Orion ST80.  The Meade is a blue metal tube.  The optics on it are very good for an achro.

I flocked the tube and replaced the stock focuser with the GSO 2" focuser (I had picked on CN classified) .  It is a great RFT grab and go.

 

Clear Skies,

Tony

[Sarkikos]

A TSFLAT2 field flattener flattens the field nicely in the ST80.  Not much you can do about the CA, though.  I never liked how the Moon or Jupiter looked in this scope.  It's best for wide-field deep sky.

 

Mike

[csrlice12]

Anybody seen the Celestron 4" f6.5 at Costco?  I noted the box said coated optics, not multicoated.  The mount was a flimsy alt/az, so why a big deal on the box for including a cell phone adapter eludes me.  Did appear to have a 2" focuser, but only had a 1.25" erecting diagonal....not worth the $200 asking price.

[George Methvin]

I have the Meade adventure scope got it new for $89.99 and I  must say it one sharp little scope when viewing the Moon at low or higher power I see very little CA and there's lots of detail to be seen very easy to see two belts on Jupiter even though the image is small but this scope really shines when viewing wide field low power objects, for the money its a best buy.  Know this the first thing I did when I got this scope was check the collimation and it was off a bit it was not center so I had to adjust the focusers to get the scope collimation right on and when I did the views through the scope sapped into focus images  were very good very sharp  even when using a 4mm eyepiece the image was very good and very dim lol.

Edited by George Methvin, 14 November 2020 - 08:58 PM.

[Tom Stock]

I had mine out last night and was getting nice low power images but when I got over 100x things became a mess.

 

Mars was a blob with no detail.

 

Surprised, I did a star test and my diffraction pattern looked like this ((((((o))

 

YUCK!

 

After some testing I discovered my budget 1-1/4" diagonal was junk and way out of collimation.  Looking thru only the diagonal with a cheshire, the cross hairs were not even CLOSE to centered.  They were at about 1/3D down and left.  It was not possible to correct with mirror adjustment, because the nose piece and eyepiece tube were not even on the same axis!

 

I deserve this because I knew better than to use a cheap chinese diagonal.

 

So check your diagonal before you assume the scope can't do it.

 

Tom

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Edited by Tom Stock, 14 November 2020 - 10:36 PM.

[George Methvin]

Yes Tom so true I had the same problem once with a cheap diagonal could not seem to get a good image the diagonal was the problem it was a piece of junk.  The Meade 80mm f/5 was showing almost the same pattern you were seeing but not quite as bad kind of like this (((0)) when I worked on the focuser alignment I got the pattern like this right in the center ((0)) and the images were much better. 

Edited by George Methvin, 15 November 2020 - 02:30 AM.

[CHASLX200]

I had mine out last night and was getting nice low power images but when I got over 100x things became a mess.

 

Mars was a blob with no detail.

 

Surprised, I did a star test and my diffraction pattern looked like this ((((((o))

 

YUCK!

 

After some testing I discovered my budget 1-1/4" diagonal was junk and way out of collimation.  Looking thru only the diagonal with a cheshire, the cross hairs were not even CLOSE to centered.  They were at about 1/3D down and left.  It was not possible to correct with mirror adjustment, because the nose piece and eyepiece tube were not even on the same axis!

 

I deserve this because I knew better than to use a cheap chinese diagonal.

 

So check your diagonal before you assume the scope can't do it.

 

Tom

I did the same thing last nite with a 45 degree diagonal and a 90mm F/10.  Stars looked like a double star at high power so i removed the diagonal and looked straight thru and i had a normal looking star image.

 

I would like a ST80 is there was some way to remove FC. We need a FC eater like a Paracorr eats coma.

[Ihtegla Sar]

I would like a ST80 is there was some way to remove FC. We need a FC eater like a Paracorr eats coma.

There is something called a TS-flat. Takahashi also makes a similar one at about the same price. They are designed for AP but can be used for visual. Problem is that they have to be at a precise location in the image train, like coma corrector, to work. There is also no adjustment mechanism, so the user has to get creative with spacers, adaptors and doing things like attaching the device directly to a diaganol in lieu of a nose piece.

They also seem to be designed for particular focal lengths/ratios so may not work well in all scopes.

Takahashi's is designed for their FC scopes. I asked Takahashi about using their version for visual and they said it would only work straight through on their scopes since there wasnt enough back focus for it to work with a diagonal.

There is a thread on the TS-flat here in the refractor forum and reading it makes it sound like whether the TS-flat will work with any particular scope is hit or miss. But I did see someone posting that it would work with a ST-80. I haven't wanted to spend the money on another gadget to be a guinea pig.

https://www.cloudyni...4#entry10653172

Edited by Ihtegla Sar, 15 November 2020 - 12:08 PM.

[CHASLX200]

I higher priced and better built flat field ST80 would be great with a 21mm Ethos and i would for sure buy one as a super sweeper as long as there was no FC.

[Jon Isaacs]

I higher priced and better built flat field ST80 would be great with a 21mm Ethos and i would for sure buy one as a super sweeper as long as there was no FC.

 

It wouldn't be cheap, it doesn't make sense to built it as an achromat, might as well make it an ED.

 

I'm using the TSFLAT2 with my Astro-Tech AT-80 LE, an 80 mm F/6 FPL-53 doublet. Spacing was tricky. I had to borrow a diagonal as replace the nosepiece with the flattener but the views are amazing. 5.5 degrees with the 41 mm Panoptic, 5.0 degrees with the 31 Nagler and 4.3 degrees at 23x with the 21mm Ethos. It's not as perfect as the NP-101 but it's close.

 

The fields are flat and sharp. I haven't tried my ST-80 yet..  the TSFLAT2 is about $200 shipped from Germany.  I got mine shipped from Prescott Az via Astromat and Jeff Morgan.

 

Jon