53 replies to this topic

[sojourneyer]

I purchased the 102 AZ for a lightweight travel scope that I can leave in my vehicle.  I will take it to Florida in three weeks because of my other scopes size and weight.  I did an extensive side by side with my ES AR102.  The Celestron held its own and for the price has exceptional optics.  However, mechanically the AR102 wins hands down.  The focuser is a very stiff 2 inch rack and pinion.  At some point I will clean out the old grease and replace it with lithium grease.  I put a 2 inch diagonal on the scope and took it off pretty quick.  You can balance the scope with a longer dovetail and 2 inch accessories but the vibrations are unacceptable even at low power.  If you use 1 1/4 inch accessories it's not too bad.  For the price, it is a fantastic deal.  The OTA is worth the cost.  I plan on doing the Messiers with it and should know a lot more by the time I am finished.  Also, you can upgrade the scope a lot if you so desire.

 

Hope that helped.

Mark,

Do you mind if I can ask you these questions

The XLT is selling for $260 and the basic 102AZ for $160

 

I believe the only difference is the eyepieces and the coating.

Is the XLT coating that much better?  I was told no but take input from all on this.

 

I think the mount is the same for the two.  The tubes look the same so would a 2 inch

diagonal be accommodated on the basic 102? 

 

What do  you have to do to put on a two inch diagonal.. I do notice that the draw tube is

very wide.. I have not taken the scope out of the box...

I need Santa to wrap it for me.. LOL

 

All in all would you recommend the basic 102?

 

thanks

Merry Christmas and happy travels
 

[LDW47]

Just as many if not more buy expensive bundles and then quit astronomy.  The Celestron Omni 102 AZ is far, far better than my first scope.. $5 at a garage sale, one 2 element eyepiece, no finder. 

 

The critical factor is not the telescope,  it's the individual. Amateur astronomy requires patience, persistence, curiosity, you can't buy that.. 

 

Sure a 4 inch apo is better optically but there's always a bigger, better telescope. Making the most of what you have, that's what it's all about.

 

Last night I spent about a hour with my 80 mm F/5 achromat. I had had my 120 mm apo out but decided I wanted a change of pace. I had some wonderful views and enjoyed the time with it..

 

My sister is a professor of modern history at the Università di Pisa. (This is true)  I think she told me she was looking through the archives and found a manuscript where Galileo said he almost gave up because he felt he needed an FPL-53 triplet instead of his crude singlet. (This is not true but makes a point.)

 

This 102 mm F/6.5 achromat is good enough.. If the first views do thrill you, if they don't light a spark that turns into an undeniable passion, nothing will..

 

I've had friends whose first look through a telescope was a night under dark skies with my 25 inch. They enjoyed but that's as far as it went.. it's not about the telescope.

 

Jon

What do you mean its not true !  LOL !

[markdaleanderson]

I have not looked through the non-XLT version of this scope but I suspect that you would have to be a seasoned observer to notice the difference and even then it may be difficult to detect.   I believe that Celestron has stated that the only difference is the coatings.  There is an adapter that fits into the focuser that allows you to install the 1 1/4 diagonal.  You take that adapter out and a 2 inch diagonal fits directly into the focuser.  The scope mount does not have clutches so it must be balanced to be usable.  The vixen dovetail attached to the scope is too far forward which makes it impossible to balance with the heavier 2 inch diagonal and eyepieces.  I happen to have a spare set of rings with a longer dovetail that I mounted right over the top of the fixed dovetail.

 

When they are high enough in the night sky, you will get beautiful views of the moon (with what my old eyes would call minor chromatic aberration), a look at the great red spot on Jupiter, the Cassini Division in the rings of Saturn and with experience all the Messiers (M74 and M33 take some experience.

 

As long as you don't expect to see Hubble images, you can a lot of fun with this scope and it can be upgraded with a better mount, rings, better focuser and eyepieces.  Hopefully, you wont' be an equipment junky like most of us.

 

Merry Christmas

[sojourneyer]

I have not looked through the non-XLT version of this scope but I suspect that you would have to be a seasoned observer to notice the difference and even then it may be difficult to detect.   I believe that Celestron has stated that the only difference is the coatings.  There is an adapter that fits into the focuser that allows you to install the 1 1/4 diagonal.  You take that adapter out and a 2 inch diagonal fits directly into the focuser.  The scope mount does not have clutches so it must be balanced to be usable.  The vixen dovetail attached to the scope is too far forward which makes it impossible to balance with the heavier 2 inch diagonal and eyepieces.  I happen to have a spare set of rings with a longer dovetail that I mounted right over the top of the fixed dovetail.

 

When they are high enough in the night sky, you will get beautiful views of the moon (with what my old eyes would call minor chromatic aberration), a look at the great red spot on Jupiter, the Cassini Division in the rings of Saturn and with experience all the Messiers (M74 and M33 take some experience.

 

As long as you don't expect to see Hubble images, you can a lot of fun with this scope and it can be upgraded with a better mount, rings, better focuser and eyepieces.  Hopefully, you wont' be an equipment junky like most of us.

 

Merry Christmas

Mark

THank you but I have some good news

 

The Omni 102 AZ  according to Celestron  ad ----New Omni manual slow-motion altazimuth mount uses worm gears for smooth, easy tracking of celestial or terrestrial targets and slip clutches for quick and easy pointing

 

So they both have slip clutches. Here is the link

https://www.celestro...z-102-telescope

 

Also I have a way to address the balancing issue.

Get an velcro ankle bracelet and affix it near the dew shield.. Or alternatively

wrap a small bungee cord around the OTA near the dew shield and attach

a small weight to it.

 

Regarding the focuser... do you mean that I just need to remove the adapter from the focus tube and I can insert a 2 inch diagonal... that is great but I have 1.25 inch eyepieces

 

Something for the future..

Perhaps the mount/ tripod will be okay with the ankle weight

[markdaleanderson]

The key word is slip clutches.  My Twilight 1 mount has clutches that you tighten once you are on an object and the slomo controls are the only way you can move the scope.  Consequently, it doesn't have to be perfectly balanced.  As I change eyepieces, I generally don't have to rebalance the scope.  The weight of the eyepieces are much more important when you have slip clutches.

[sojourneyer]

The key word is slip clutches.  My Twilight 1 mount has clutches that you tighten once you are on an object and the slomo controls are the only way you can move the scope.  Consequently, it doesn't have to be perfectly balanced.  As I change eyepieces, I generally don't have to rebalance the scope.  The weight of the eyepieces are much more important when you have slip clutches.

Their website says it has slip clutches.. Does yours?

The twilight 1 weighs more than the scope...

Could you please give me your comments regarding the

focuser.. ?

thanks so much
 

[markdaleanderson]

Yes, mine has slip clutches which is why I am using a 1 1/4 inch diagonal and eyepieces of approximately the same weight.  I also have a zoom eyepiece which allows me to go from 7.5mm to 22.5mm focal length without changing anything so no need to rebalance.  Having a mount that weights more than the telescope is a good thing.  The problem with most commercial telescopes, especially the more inexpensive scopes, is that they are under mounted.  I have a fairly high tolerance for vibrations, some do not.  The focuser is stiff because of the grease they use to lubricate them.  I will eventually clean the grease out with mineral spirits and grease it with some lithium grease I have.  A stiff focuser can be quite frustrating at higher powers especially when you are used to very expensive two speed crayford focusers.

[sojourneyer]

Yes, mine has slip clutches which is why I am using a 1 1/4 inch diagonal and eyepieces of approximately the same weight.  I also have a zoom eyepiece which allows me to go from 7.5mm to 22.5mm focal length without changing anything so no need to rebalance.  Having a mount that weights more than the telescope is a good thing.  The problem with most commercial telescopes, especially the more inexpensive scopes, is that they are under mounted.  I have a fairly high tolerance for vibrations, some do not.  The focuser is stiff because of the grease they use to lubricate them.  I will eventually clean the grease out with mineral spirits and grease it with some lithium grease I have.  A stiff focuser can be quite frustrating at higher powers especially when you are used to very expensive two speed crayford focusers.

where do you get lithium grease?

[markdaleanderson]

I think most hardware stores carry white lithium grease.  I don't remember where I purchased it.

[eros312]

where do you get lithium grease?

Any hardware store will have it. Here's Home Depot https://www.homedepo...10533/202535870

[sojourneyer]

Any hardware store will have it. Here's Home Depot https://www.homedepo...10533/202535870

thank you fellows

is it in a tube?

[eros312]

Yep. 

[sojourneyer]

Yep. 

thanks and merry xmas

[Binojunky]

Binoman...I am a bit confused. Are you saying that the Amazon scope came with those changes or you made them? 

 

What unit are you referring to ?

 

thanks

These were  my modifications, also forgot to mention that I replaced the plastic focuser knobs with a nice set of metal ones, Dave.

Edited by Binojunky, 21 December 2019 - 12:15 PM.

[gjanke]

I picked up just the OTA locally 2 years ago for $85. I found it be a servieable scope. It does show CA as expected. However, as a beginning scope it was good for someone new to the hobby or for star parties. 4" refractors IMHO are truly made for the moon and planets and the Celestron will serve you well. If you were to look into a ED or triple, cost aside, the detail masked by the CA is astounding and you will see why others upgrade once they move past beginners and buy more expensive telescopes.

I made no changes to the focuser because its a waste of money to do so. I would upgrade to better eyepieces because, you can reuse them on any scope you buy. Just remember type of scope and focal length need to be considered why putting money down on the eyepieces.

I keep mine for the summer and sold it to a gentleman up in New Jersey for the same price I bought it for. I will tell you he later complained of all the purple he was seeing on the moon and when I explained to him that was the nature of Achros and to do some research to verify what I was saying to him was true, I never heard from him again.

So great beginners scope, don't send any money upgrading it all at. If you decide you want to stay in the hobby sell it and get something a little nicer.

Edited by gjanke, 21 December 2019 - 12:59 PM.

[sojourneyer]

These were  my modifications, also forgot to mention that I replaced the plastic focuser knobs with a nice set of metal ones, Dave.

Aha... I got confused when you said you got it from Amazon and then mentioned all the changes.. I could not understand how Amazon would sell a modified scope..

Thanks for the reply

[sojourneyer]

I picked up just the OTA locally 2 years ago for $85. I found it be a servieable scope. It does show CA as expected. However, as a beginning scope it was good for someone new to the hobby or for star parties. 4" refractors IMHO are truly made for the moon and planets and the Celestron will serve you well. If you were to look into a ED or triple, cost aside, the detail masked by the CA is astounding and you will see why others upgrade once they move past beginners and buy more expensive telescopes.

I made no changes to the focuser because its a waste of money to do so. I would upgrade to better eyepieces because, you can reuse them on any scope you buy. Just remember type of scope and focal length need to be considered why putting money down on the eyepieces.

I keep mine for the summer and sold it to a gentleman up in New Jersey for the same price I bought it for. I will tell you he later complained of all the purple he was seeing on the moon and when I explained to him that was the nature of Achros and to do some research to verify what I was saying to him was true, I never heard from him again.

So great beginners scope, don't send any money upgrading it all at. If you decide you want to stay in the hobby sell it and get something a little nicer.

Thanks for the input
Was it the basic 102AZ or the XLT?

The only changes I might make are the diagonal and mount, if at all

I will only be a casual observer and have too many other pursuits to

upgrade the scope..... But who can ever know?? LOL

[gjanke]

Thanks for the input
Was it the basic 102AZ or the XLT?

The only changes I might make are the diagonal and mount, if at all

I will only be a casual observer and have too many other pursuits to

upgrade the scope..... But who can ever know?? LOL

It was the XLT. A good mount can always come in hand if you stay in the hobby. If its for quick looks and showing neighbors the moon and planets you really don’t need much more. You can show them some brighter Messier objects and you can get a solar filter and show them the sun. I think you have exactly what you need for this hobby.

Edited by gjanke, 22 December 2019 - 12:02 AM.

[bjahns]

I know it's a year old, but as I just picked up one of these at Costco a month or two ago for $199....

 

The Omni AZ 102 comes with two eyepieces a Celestron branded K10mm (assuming that's for Kellner) (from what I can find online, the AFOV is 50deg) and a Celestron branded 20mm (no other markings on it). Neither have any eye relief. I'm wondering what the 20mm one actually is (specifically the AFOV) as I'm entering in all my equipment into SkySafari (just to keep track of stuff). Anyone have any ideas?

Edited by bjahns, 09 December 2020 - 05:56 AM.

[jmccown]

I have the Omni AZ 102 f/6.5

 

To put it simply, I love the scope and hate the mount. For some reason, I was expecting a decent Alt-Az mount. Mine is not, but I think other people have had better luck. The altitude slo-mo control went out not long after the scope arrived. I have to push the tube up and down with my hand. I sent it back for warranty. Celestron 'fixed' it, and then it resumed slipping after just a week or two.

 

For a better mount, I bought a Twilight I off the classifieds on this site and the scope is a good match for it.

 

The scope is great. It's not much use for planets but for DSOs it gives nice views with clear, wide fields. You don't have to spend $600 on a Televue eyepiece to get a good look at M31, M42, M45, M81/82, and many other interesting objects. I usually use an Astro-Tech 25 mm Plossl with good results. It's a fast achro, but chromatic aberration is not a big problem for observing DSOs.

 

 

 

 

[sojourneyer]

I had the same problem with the mount on the Omni 102AZ

It was especially bad with a barlow and Zoom eyepiece.  I bought a Twilight 1 as well and it worked just great.  I wish I had purchased the Vixen Porta 2 because it is a tad lighter than the TW1 which is over 18 lbs. 

 

Actually the Omni is not bad for the planets so long as  you keep the Magnification under 150X

And I suggest you do not go overboard with the EPs because the Objective is the overriding component to viewing.

The CA on the moon did not bother me at 200X but then I got a 127 Mak and wow the difference.

 

It is a very good scope and 4 inches is a perfect size.  At f/6.5 you can get it up to about 200X with a 6mm EP and 2X barlow and that is my limit with this puppy.

 

Two things you might consider for the future... get a GSO dual focuser (it does wonders) and a 8-24 Zoom Eyepiece.  Then all you have to do is insert the 2x barlow and the Zoom and your evening is set.

[Voilam]

hi everybody

 

This is my combine set-up with Celestron AZ 102,

 

Staying very close to the airport, it is huge of light pollution. With this set up, I could quick carry it around the neighbor-hood. 

I get a nice view - to my opinion - of Jupiter, Saturn, Moon, Mars, Venus... Orion nebula, 7 sisters

 

& hope to discovery more object up in night sky.

 

Wishing all happy & healthy year 2021

 

[erin]

Nice set up! Those are fun scopes. What are the tripod legs in the pic?

[Voilam]

Nice set up! Those are fun scopes. What are the tripod legs in the pic?

It actually the camera tripod Velbon mark 6 with fluid head, I remove the head connect thru a 1/4" crew. & then insert a 3/8" thread to fit AZ mount.

[erin]

Thanks! Looks sturdy.

 

I like using heavy duty tripods for lighter scopes and binos.