First Scope Confusion

[LoneStar]

Hello there!

I've been reading the forums for a while, but decided to take the plunge and join

After a couple of years enjoying the skies through my 15x70 binoculars in my back garden, I'm ready to look for my first telescope.

I've been researching online and reading up as much as I can, but as I'm unable to go out due to illness, I'm unable to try anything out for myself.

I would mostly like to view nebulas, galaxies and star clusters...and obviously planets, but the former is more important to me.

I don't have 360 deg views of the sky as there are houses around me...and there is a bit of light pollution, but not too much.

My budget can be pushed to £400 and I would prefer not to have GoTo as I want to learn the skies and I understand you can't use the scope without it/can't turn it off. I'm realistic of what I can expect to see in my budget.

I have to mention that I need the scope to be light and portable as I'm only 5 feet tall, and not too strong at the moment so Dobs and large and long scopes are out....therefore, I have been looking at the following scopes in order of easy of portability:

Skywatcher Startravel 120 (EQ 3-2) 5" Refractor f/5

Celestron OMNI XLT 120 (CG-4) 5" Schmidt Cass f/10

Skywatcher Explorer 150 (EQ 3-2) 6 " Reflector f/5

I'm not that great on the terminology yet, but I understand I will get wider field views on the refractor (and some colouring), but less wide on the XLT 120 as it's slower. The Explorer 150 looks a middle ground being 6" but is bigger than I might be able to manage and the mount perhaps not as stable. I will possibly want to add a motor in the future to take pictures/image to catalogue what I've seen.

I just wondered if any of you had any of the scopes? As I say, Dobs are out but wondered your thoughts?

Thanks for reading

[happy-kat]

Hi

Funny you should mention the startravel I read this review only a few days ago some interesting reading on that site too.

http://www.scopeviews.co.uk/StarTravel102.htm

An equatorial mount might be on the heavier side, a simple AZ based mount may be lighter and is straight forward to use.

I have both a small dob and a small refractor.

Both I use sitting but the short f5 refractor on a partially extended AZ3 tripod is way more comfortable to use. I have made a very cheap counter weight for this tripod to help with balancing my ST80.

Plan in your budget one good mid zoom eye piece I use my 16mm the most and it is a better than budget one at approx £69.00 but worth it for the views. Do I like the lovely pin point stars of my small refractor yes I do.

AZ is fine for imaging the planets and the moon but no good for DSO. An equatorial mount is I think heavier and requires more than a plonk and go setup.

[happy-kat]

Could get a second hand equatorial driven mount in the future to use worth the telescope or just a camera in the future.

[Vox45]

Hi LoneStar,

I would say that if you want something small and portable then a Schmidt-Cassegrain is the way to go, and, for astrophotography, it's easier to use IMHO. A Maksutov-Cassegrain also is short and easy to use and good for planetary but a bit slow for deep sky. The Skywatcher Explorer 150 (EQ 3-2) 6 " is much bigger and there are some issues when switching to astrophotography with a newton scope (houuu I just started a war with that statement)

You can go the refractor way, but for the same price you get bigger aperture on a reflector.

Also, the Celestron OMNI XLT 120 (CG-4) 5" Schmidt Cass f/10 you refer to is not a Schmidt-Cassegrain, it is a refractor according to Celestron's spec. Am I looking at the wrong one ?

www.celestron.com/browse-shop/astronomy/telescopes/omni-xlt-120-telescope

I disagree on the goto part of your statement, you can still learn with it and it will be far less frustrating (especially in a light polluted environment) when comes the time to find a very dim object using a goto.

There are small Dobsons that are very cool but not adapted to photography.

I'll let others join in as I know that there are a lot of opinions and each setup have their own pro's and con's

Cheers

[ronin]

My budget can be pushed to £400 and I would prefer not to have GoTo as I want to learn the skies and I understand you can't use the scope without it/can't turn it off. I'm realistic of what I can expect to see in my budget.

If you do not know the sky then actually you cannot realistically tell the goto where to goto.

Also I doubt that anyone with a goto actually blindly trusts the things so they know exactly where they are supposed to go and aim at in the sky. If I asked for Arcturus and it put Vega in view do you think I, or anyone with a goto, would not know the difference?

In effect you know exactly where things are, where the scope should goto and if it has gone there. And two of those 3 you know before you even have to switch the goto on.

I could argue the other way:

Have a dobsonian see a nice bright star/object but not sure what it is - doesn't matter as you can aim the scope at it anyway. So still don't know what you were observing.

Cannot easily do that with a goto. You have to know what it is to instruct the goto. So you actually need to learn the sky more with a goto.

What you can also do with a goto is to slew the scope to the unknown star/object, centre it and ask the goto what it is you are observing. A 150P dob isn't going to do that. So you can learn as well from a goto.

[Vox45]

I would also add that you can do tracking with a goto mount. The mount should be an EQ mount (equatorial) for astrophotography.

Now lets not get carried away as when we start to walk into the realm of astrophotography, the money involved tend to go up.

So you might want to start with a small 5" Schmidt-Cassegrain on an EQ3 goto mount and build up from there. You would have a lightweight setup for visual and you can build on this for astrophotography. Buy second hand if you can as a lot of us sell our stuff for something bigger once we get the hang of it. Start small, buy second hand.

Cheers

[Kropster]

A dob is not heavy in two bits and for galaxies, nebulae and the like you will need aperture..... you get more per £ with a dob.

They are also very light and quick to move around the sky.

Put a setting circle on the base and add a cheap inclinometer and you will easily find targets.

[Steve-G]

I assume you mean Celestron OMNI XLT 127 Schmidt Cass f/10 as the XLT120 is a refractor.

I can't comment on the other scopes you've listed but I've had an OMNI XLT127 for a while now. I mainly use it in the back garden, which is quite light polluted, but It's been great for planetary viewing, bright DSO's & open clusters & I love it for it's ease of use & portability. However, I can't say the same for the CG-4 equatorial mount which is a bit of a lump to have to cart in & out of the house. Also bear in mind that being a Schmidt Cassegrain you will need to allow a good hour or so cool down time for the scope before the view stabilises. In practice, I've found the hour cool down to be just about the same time it takes for condensation to start forming on the 5" objective lense so you would also need to fit a decent dew shield. On the plus side, being a slow (F10) scope means it's quite forgiving on eyepieces so you won't have to spend big bucks on top of the range kit to get decent views. 

[LoneStar]

Thanks so much for your replies everyone....lots to think about!

As you might have guessed, I made a typo, I did indeed mean the Omni XLT 127 not 120 as I typed (Doh!) http://www.celestron.com/browse-shop/astronomy/telescopes/omni-xlt-127-telescope

I obviously have to weigh it all up...I was initially leaning towards the Startravel 120 as there will be less cool down, it's quite portable and I thought might be good to learn on and I'd see a fair bit...(I did learn my way around the sky quite a bit on my binocs and have just purchased 'Turn Right at Orion' and am studying it on cloudy nights....which would be every night just lately

Having said that, it's interesting what you say about the GOTOs. I am, at the moment, only going to be having short viewing times so I'll need to plan ahead as to what I'm wanting to see. A Goto would help with speed I guess. As I am beginning to come back to health, I'll hopefully be up to much longer sittings (thermals will need to be ordered ). I guess at the back of my mind, I worried about Gotos breaking on me at some point. This scope is going to be all I can afford for quite some time. I'm sure they don't break often....I guess this girl just worries too much! I did briefly look at the Celestron 127 SLT actually!

Thanks though. Lots and lots to consider!

[happy-kat]

If you are only observing for brief times then the quicker the set up time and the quicker the scope is ready for viewing is a bonus.

A scope with an hour to cool down might be quicker if you can leave it outside in a shed I guess.

Some rough weighs found on google, these things are heavier then they look.

Celestron 127 OTA 2.9 kilos

The Startravel 102 OTA weighs I think 2.6 kilos

The 120 OTA weighs 3.9 kilos

Add tripod and accessories like diagonal and eyepeice and finder etc.

EQ3-2 pro mount weighs 16 kilos perhaps some of this is the weights which can be carried separately.

AZ4 8.1 kilos

AZ3 5 or so kilos

The search on this site works really well and might find you reviews on each of the scopes and mounts you are thinking off.

[LoneStar]

If you are only observing for brief times then the quicker the set up time and the quicker the scope is ready for viewing is a bonus.

A scope with an hour to cool down might be quicker if you can leave it outside in a shed I guess.

Some rough weighs found on google, these things are heavier then they look.

Celestron 127 OTA 2.9 kilos

The Startravel 102 OTA weighs I think 2.6 kilos

The 120 OTA weighs 3.9 kilos

Add tripod and accessories like diagonal and eyepeice and finder etc.

EQ3-2 pro mount weighs 16 kilos perhaps some of this is the weights which can be carried separately.

AZ4 8.1 kilos

AZ3 5 or so kilos

The search on this site works really well and might find you reviews on each of the scopes and mounts you are thinking off.

Thank you so much for taking the time to check that for me. I really appreciate it

I'm armed with some great info here. I'll take your advice and search the reviews too.

[Astro Imp]

Thanks so much for your replies everyone....lots to think about!

As you might have guessed, I made a typo, I did indeed mean the Omni XLT 127 not 120 as I typed (Doh!) http://www.celestron.com/browse-shop/astronomy/telescopes/omni-xlt-127-telescope

I obviously have to weigh it all up...I was initially leaning towards the Startravel 120 as there will be less cool down, it's quite portable and I thought might be good to learn on and I'd see a fair bit...(I did learn my way around the sky quite a bit on my binocs and have just purchased 'Turn Right at Orion' and am studying it on cloudy nights....which would be every night just lately

Having said that, it's interesting what you say about the GOTOs. I am, at the moment, only going to be having short viewing times so I'll need to plan ahead as to what I'm wanting to see. A Goto would help with speed I guess. As I am beginning to come back to health, I'll hopefully be up to much longer sittings (thermals will need to be ordered ). I guess at the back of my mind, I worried about Gotos breaking on me at some point. This scope is going to be all I can afford for quite some time. I'm sure they don't break often....I guess this girl just worries too much! I did briefly look at the Celestron 127 SLT actually!

Thanks though. Lots and lots to consider!

First let me say that I have never used GOTO but have read plenty of threads from newcomers who went down this route.

If you are limited to short viewing times it is likely that your time will be spent setting up the GOTO and in addition to the initial purchase you will need to factor in the price of a power supply.

As you have been using bins. for a couple of years it's likely that you have a reasonably knowledge of the sky, at least the major constellations which is a great start.

As you can see from my signature I use the SW 150P on an EQ-3 mount and love it. Would I recommend it to you? - no. Why, a Newtonian on an equatorial mount puts the eyepiece in some impossible positions and means the tube needs to be moved in the rings which is taking up more of your observing time.

You don't say where you are situated but a search would likely find a local club that you could visit and see various scopes in use to help make your choice. You may find this a help in finding a club:- http://fedastro.org.uk/fas/members/members-a-z/

Good luck.

[JG777]

As you soon find out there is no perfect answer to what the best set up would be, always some kind of compromise. I had a Startravel 120 on AZ4 which was a good combo although not spectacular on moon and planets it held its own on the other stuff. I use a Mak 127 on the AZ4 as well, very easy to cart around and very stable, preferred it to the ST120 for ease of use and it is a good all rounder. The Maks view is narrower and takes a little more time for cool down but nothing drastic. In a recent purge of gear I let the ST120 go and withdrew the sale on the Mak as I realised I still loved her......  My other small scope is a 100 ED APO which returns fabulous views wherever you poke it and is more than happy on AZ4, they cost more though but you may nab one for a good price second hand and stay within or near your budget.

For short sessions keep it simple and light. Good luck

[Kropster]

When I started using a telescope what shocked me was how small the field of view is and consequently, how difficult it was to find anything!

Goto saved the day. A quick polar alignment, then may be two bright stars (one if you are feeling lazy) and off you go.... 10 minutes max.

I found it saved a lot of time searching and sweeping for objects and kept my enthusiasm from drowning in a sea of frustration.

So, I definitely recommend goto for the beginner.

[happy-kat]

What was your scope though?

My 130 newt is narrow, my 80 refractor is lovely and wide fov and my 70 mac is a drinking straw. Also the looking down to newtonian is against the brain for me on positional looking, with a refractor it feels more intuitive or I guess a bigger mac.

[LoneStar]

Thanks again everyone! I've taken all of your advice on board and had a good look around at the board reviews, as well as having some great email support from First Light Optics.

...after much pondering, I feel that I will go for the Skywatcher Startravel 120 Refractor. Although it's more expensive than the reflectors, I feel that it will get me up and running in my current, restricted state of health. I'm looking into maybe buying the body and EQ mount separately....I feel that it might be best to invest in an EQ mount that will allow me to buy a different scope (eg larger reflector) in the future when I've got more strength and can stargaze for longer periods.....preferably, one that I can either buy a motor drive or GOTO attachment, should I feel I would like to start taking photographs.

You've given me some great advice and I can't wait to start gazing at the heavens....there's something quite peaceful/healing about it

[southernman]

As a recent purchaser of the startravel 120 I don't think you will be disappointed. I have mine mounted on an eq mount similar to the sw eq3-2. Although not the lightest combination it still works as a grab'n'go and provides wonderful low power views.

Peter

[Kropster]

Unless we are talking binocular fields of view, I think for a beginner, a telescope is difficult to point at a particular object...especially fuzzies and faint nebulae.

The sky is vast and if you don't know your way around, easy to get lost in.

Go to is a great aid... you don't have to use it, but it is mighty handy to have as a back up.

[Uhwaz]

about goto ... even if you not guiding and running just RA motor it ll help a lot with keeping your object in field of view 

I remember how surprised i was at the speed jupiter was moving the first time i was looking at it at 200x mag without goto turned on 

[LoneStar]

Hi again everyone,

I apologise for dragging my thread back out again...I didn't feel right starting a new one.

It's been over a week and I'm still pretty much stuck on my decision on what to get. I was getting quite disheartened so I've decided to stop searching a try and figure out what's most important to me in regards stargazing..

I do have one question regarding two of the scopes I was originally considering though.... (Apologises again if it's a stupid question!). I originally had my heart set on the Skywatcher Startravel 120 (EQ 3-2) 5" Refractor f/5 but had been suggested by many in the last few days to get the Skywatcher Explorer 150 (EQ 3-2) 6 " Reflector f/5 instead. Am I right in thinking that as it's also an f/5, the Explorer will give me similar wide-field views at low magnifications in the same way the fractor would...minus the AC but with possible coma?

Thanks again

[LoneStar]

Edit: CA not AC! (Doh!)

[happy-kat]

I can't comment re comma though for observing perhaps it does not matter and if looking to image then the 150pds is better set up for that.

As a thought the reflector will give you an inverted image and the refractor can give you a right way up image. Are you fused about image orientation?

There is a chap who has just literally got a startravel 120 on a eq Mount could wait and see what they review it like if that helps.

[RichieP]

Hello

It is a common misconception that the focal ratio affects the field of view. it doesn't.

The only factor which does , for a given eyepiece, is the focal length of the scope. Smaller focal lengths give lower magnifications which gives you a larger true field of view.

To say that two scopes at F5 have the same field of view will only be true if the have the same aperture.

The ST120 at F5 would have a focal length of 600mm whereas the Explorer at F5 has a focal length of 750mm.

So the ST120 will give the widest field views, although the Explorer still isn't bad in that respect.

Richard

[LoneStar]

I can't comment re comma though for observing perhaps it does not matter and if looking to image then the 150pds is better set up for that.

As a thought the reflector will give you an inverted image and the refractor can give you a right way up image. Are you fused about image orientation?

There is a chap who has just literally got a startravel 120 on a eq Mount could wait and see what they review it like if that helps.

Thank you for the fast reply. I'm increasing thinking of forgetting any photography and just enjoying the views

I'll look about for that review! Would love to see what they think!

[LoneStar]

Hello

It is a common misconception that the focal ratio affects the field of view. it doesn't.

The only factor which does , for a given eyepiece, is the focal length of the scope. Smaller focal lengths give lower magnifications which gives you a larger true field of view.

To say that two scopes at F5 have the same field of view will only be true if the have the same aperture.

The ST120 at F5 would have a focal length of 600mm whereas the Explorer at F5 has a focal length of 750mm.

So the ST120 will give the widest field views, although the Explorer still isn't bad in that respect.

Richard

Thanks so much for clearing that up for me. I guess I keep confusing myself! I'm no good when there are many options!