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Advice regarding telescope


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Hi,

Probably you are tired receiving these kind of requests :) , yet me, the newbee, wants to get a telescope. I was wondering if  I've made the best choice, and if not... maybe you give me and alternative.

The situation is as follows :

1. I have never used a telescope before (but I am overwhelmed when I see pictures of planets)

2. I want to observe planets mainly, the sun, the moon, and last DSO (I guess I can't get too much regarding DSO's, from such a budget)

3. My budget is ~650e (or less...)

4. I chose Celestron Omni XLT 120 (in my country it costs 650e...)

5. Definately I would love to make astrophotography in future with my telescope, I own a DSLR .. but that is another story and I need to master basics before getting intro astrophoto.

How do you see the learning curve regarding the XLT120 use?

Can you offer me a better solution for planet watching (or nice DSO) than the XLT120?

Thank you in advance for your patience,

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I think the XLT 120 is a very good first choice and should give you lots of pleasure in the years to come.  It should give great views of the planets and the Moon, however, it is not the best scope for astrophotography as it has no tracking.  The Nexstar series do have this function but I suggest you get familiar with the night sky first using the XLT, it is a very capable scope for visual use.

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I have the OMNI XLT 120mm on a CG-4 mount.

Before going on, let me caution you about viewing the Sun... Don't even attempt it without the proper equipment (ie: a filter, etc.)  Even exposing your finder scope (unprotected) can damage it.

The XLT is a very good achro refractor.  It demonstrates very little Chromatic Aberation, even on a bright planet like Jupiter.  I've viewed dozens of DSOs with mine.

The mount will track well enough for medium exposures when properly polar aligned and employing an optional RA drive motor.

The mount provides the hole in the RA axis for a polar alignment scope, but it's not necessary unless one is doing serious tracking.

Clear Skies

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I have the OMNI XLT 120mm on a CG-4 mount.

Before going on, let me caution you about viewing the Sun... Don't even attempt it without the proper equipment (ie: a filter, etc.)  Even exposing your finder scope (unprotected) can damage it.

The XLT is a very good achro refractor.  It demonstrates very little Chromatic Aberation, even on a bright planet like Jupiter.  I've viewed dozens of DSOs with mine.

The mount will track well enough for medium exposures when properly polar aligned and employing an optional RA drive motor.

The mount provides the hole in the RA axis for a polar alignment scope, but it's not necessary unless one is doing serious tracking.

Clear Skies

A very timely warning and what came immediately to mind when I first read the OP.

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Thank you for your answers, but allow me to add one more question.Later I have found another similar (both from a characteristics and a budget point of view) telescope :  Sky-Watcher 1201EQ5

This one, compared to the Omni XLT 120 has a better finder 9x50 compared to 6x30, a little better magnitude (0.2) and some say it also has a better mount.

Should I better go for this one, or remain to the original choice : Omni XLT 120?

Thank you again for your time,

P.S.: maybe somebody can share his/her experience in case he used both telescopes?

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Hi,

Probably you are tired receiving these kind of requests :) , yet me, the newbee, wants to get a telescope. I was wondering if  I've made the best choice, and if not... maybe you give me and alternative.

The situation is as follows :

1. I have never used a telescope before (but I am overwhelmed when I see pictures of planets)

2. I want to observe planets mainly, the sun, the moon, and last DSO (I guess I can't get too much regarding DSO's, from such a budget)

3. My budget is ~650e (or less...)

4. I chose Celestron Omni XLT 120 (in my country it costs 650e...)

5. Definately I would love to make astrophotography in future with my telescope, I own a DSLR .. but that is another story and I need to master basics before getting intro astrophoto.

How do you see the learning curve regarding the XLT120 use?

Can you offer me a better solution for planet watching (or nice DSO) than the XLT120?

Thank you in advance for your patience,

Dyptorden.....We wouldn't  be here if that was the case. Welcome to the SgL. 

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Dyptorden,

I do not own the Omni XLT 120, nor have I ever looked through the refractor but just looking at the numbers, I can try to make a few insights/suggestions  :p

Being a 120 frac, it is going to be quite large and quite long, so you're going to need quite a sturdy mount for it. The obvious question, then, is what mount comes with the frac? This is important to know, for you don't want to be lumbered with an undermounted scope and having to fork out more cash in the future.

Optically, I imagine the achro will perform very nicely, but the 120 will have chromatic aberration (CA) or false colour and this is a simple fact of life when it comes to achromatic refractors. Now, I guess CA is not an obvious issue when observing deep sky objects (DSOs), but it will affect the quality of image when it comes to viewing brighter objects like the Moon or Jupiter. Some people are more sensitive to CA than others, so obviously what irritates one visual observer might not bother another but I'd suggest you try to find some local astronomers and try out a similar type of scope before purchasing. I mean, it would be an awful shame to buy something and only after purchase realise it isn't performing as you would have liked.

Another point, an aperture of around 4.8" will be great on the Moon, Jupiter, Saturn etc but the drawback may come if you ever decide to view DSOs. The 'problem' now will be aperture. Unless you've got reasonably good dark skies, you may find that DSOs through the 120 a tad disappointing.

This leads me on to your suggestion of trying your hand at astro-photography in the future. Again, I know nothing about this subject but I think I know enough to realise that your first problem isn't going to be the scope. As far as I can gather, in order of priority for astro-photography is first the mount, then then camera, and after all that, the scope. Adding to this 'problem' is the high possibility that a refractor which is nice for general visual work, will probably be next to useless for serious photography.

This leads me to one more concern. A decent 8" dobsonian reflector is about the same price as an unmounted decent 4" achromatic refractor. The 200p from Skywatcher, for example, is just a smidge more expensive than an unmounted Tal 100rs. It might not be the same in your own case, but most beginners want to see a little of everything and at a decent price. If you are looking for faint DSOs like globular clusters, nebulae or galaxies you need aperture and low magnification, the former to get as much light as possible and the latter to get as wide a view as possible. Newtonians excel at all these factors and because of their light gathering capacity, they are also excellent scopes for viewing the Moon and planets.

If you're worried about weight and size, my Tal 100rs on an AZ 4 takes up a bigger footprint than my 10" truss dob and weighs about 6kg or 7kg less - which in the grand scheme of gear isn't that much.

Now all this isn't to put down fracs! I mean, I've got two of them and wish I had cash to buy more. They are simply a joy to use and I have never seen stars looking so gorgeous as when seen through a frac but for now, don't go blowing your money just yet. There's no hurry :grin:

Have a serious think about what you'd like to be seeing and doing over the next year or so. Is it strictly solar system work (never, ever, ever observe the sun without the proper filters in place), a bit of everything or astro-photography? If possible, get yourself along to a local astronomy club and look through the type of telescopes you think you may purchase and see if the view meets your expectations. Most stargazers will be only too happy to help. If that doesn't come off, stick around SGL, set up more threads if need be and keep asking questions.

Another thing to look out for - and I think this is really important - are astronomy sketches. If you have a look at the type of telescope from which the sketch was made this is the kind of thing you will see when observing from a telescope of similiar aperture.

I hope this helps to some extent and welcome to SGL :smiley:

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Thank you for your answers, but allow me to add one more question.Later I have found another similar (both from a characteristics and a budget point of view) telescope :  Sky-Watcher 1201EQ5

This one, compared to the Omni XLT 120 has a better finder 9x50 compared to 6x30, a little better magnitude (0.2) and some say it also has a better mount.

Should I better go for this one, or remain to the original choice : Omni XLT 120?

Thank you again for your time,

P.S.: maybe somebody can share his/her experience in case he used both telescopes?

The actual scope is pretty much the same that is same optics from the same factory but rebadged. the coatings maybe slightly different but the skywatcher evostar is a good scope   and it is better suited  to the eq5 mount  as it is a very big scope. 

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Also i did find (at same price) this telescope : Bresser Telescope AC 127/1200 Messier EXOS-2

This one has better aperture than both I have presented before, but I don't know anything about that brand.. how good is it compared to Celestron or Sky-Watcher.

Scope Aperture Focal Length Tube Length Magnitude Finder Scope Resolution Focal Ratio Mount Sky-Watcher 1201EQ5 120 1000 1040 13.1 9x50 0.96 f/8 EQ5 Celestron Omni XLT 120 120 1000 1010 12.9 6x30 0.97 f/8.33 CG4 Bresser AC 127/1200 Messier 127 1200 1260 12.3 8x50 0.91 f/9.4 EXOS-2

Could you give me some final thoughts taking these into consideration? (also I don't know much about the f/ ... should it be small...big...).

Again I thank you very much.

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looks like the forum didn't keep my formatting as a table..sorry... i put the same info below:

Scope Sky-Watcher 1201EQ5 - Celestron Omni XLT 120 - Bresser AC 127/1200 Messier
Aperture 120 - 120 - 127
Focal Length 1000 - 1000 - 1200
Tube Length 1040 - 1010 - 1260
Magnitude 13.1 - 12.9 - 12.3
Finder Scope 9x50 - 6x30  8x50
Resolution 0.96 - 0.97 - 0.91
Focal Ratio f/8 - f/8.33 - f/9.4
Mount EQ5 / CG4 / EXOS-2

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If it was me, the SW Evostar has a great reputation in these parts, I would go for this.  SW products have a good and consistant reputation.  The 120 at 1000 fl and ratio of f/8.33 is a perfect combination in my books. I would choose an AZ mount but nothing wrong with the EQ5.

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