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Choosing a telescope?


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I’m looking to buy a telescope, preferably a Dobsonian. I’m not sure which model is best for it’s price. I know someone with a skywatchers 6 inch, how would you rate that compared to other Dobsonians? Also what else should i look to buy along side a telescope?

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Welcome to the SGL.

The 6" Dobsonian fromSkywatcher would be a sensible choice for dipping your toes into the hobby of astronomy, and the recommendation is based on visual use astronomy only! don't think cameras here using a basic Dobsonian telescope.
The 8" will have more light gathering ability due to its larger surface across the primary mirror.
The 10" even more and so on.

I bought the 8" Skyliner, and all the eyepieces in my collection work admirably for my needs, however, you don't need that many.
To compliment this scope two eyepieces would suffice, a 12mm and something in excess of 25m, my preference the 32mm Panaview from Skywatcher.

Additional extras, there are several, but essentially a Cheshire collimation tool would be advisable to collimate the scope ( aligning the optics for best performance ) and some eyepieces that YOU find comfortable, but I have no hesitation in suggesting the BST Starguiders. Only issue I have with Starguiders, they don't produce a 6mm, so instead I've chosen to use the William Optics Super Planetary 6mm. Failing that their is the 12mm BST Starguider, which, when used with a Barlow adaptor of 'times two' (2x) It's the equivalent of using a 6mm eyepiece for 200x power/magnification when I need it, which again, this scope is capable of producing. A comfortable seat ( I uses a Drum stool,  height adjustable, and I have tried the famous Tetrad finder, but prefer the basic finder scope, finding targets with 'both eyes open', believe me, it works.

The 6" scope IMHO has the more basic rack & pinion focus adjuster, and although made of metal, I think the smoother Crawford adjuster on the 8" is a winner, as is the greater amount of light collected over the 6" scope. Your local conditions should be taken into consideration too. If your blessed with inky black skies and no light pollution, you may see more through the 6" than I can through the 8" from my back yard.

So many issues to contend, but have a good think, take your time, there's really no rush, and keep asking questions. HTH.

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22 hours ago, Charic said:

Welcome to the SGL.

The 6" Dobsonian fromSkywatcher would be a sensible choice for dipping your toes into the hobby of astronomy, and the recommendation is based on visual use astronomy only! don't think cameras here using a basic Dobsonian telescope.
The 8" will have more light gathering ability due to its larger surface across the primary mirror.
The 10" even more and so on.

I bought the 8" Skyliner, and all the eyepieces in my collection work admirably for my needs, however, you don't need that many.
To compliment this scope two eyepieces would suffice, a 12mm and something in excess of 25m, my preference the 32mm Panaview from Skywatcher.

Additional extras, there are several, but essentially a Cheshire collimation tool would be advisable to collimate the scope ( aligning the optics for best performance ) and some eyepieces that YOU find comfortable, but I have no hesitation in suggesting the BST Starguiders. Only issue I have with Starguiders, they don't produce a 6mm, so instead I've chosen to use the William Optics Super Planetary 6mm. Failing that their is the 12mm BST Starguider, which, when used with a Barlow adaptor of 'times two' (2x) It's the equivalent of using a 6mm eyepiece for 200x power/magnification when I need it, which again, this scope is capable of producing. A comfortable seat ( I uses a Drum stool,  height adjustable, and I have tried the famous Tetrad finder, but prefer the basic finder scope, finding targets with 'both eyes open', believe me, it works.

The 6" scope IMHO has the more basic rack & pinion focus adjuster, and although made of metal, I think the smoother Crawford adjuster on the 8" is a winner, as is the greater amount of light collected over the 6" scope. Your local conditions should be taken into consideration too. If your blessed with inky black skies and no light pollution, you may see more through the 6" than I can through the 8" from my back yard.

So many issues to contend, but have a good think, take your time, there's really no rush, and keep asking questions. HTH.

 Thank you so much for th feedback! I didnt expect one so fast. I do have a few more questions, what is the difference between buying dobsonians from (e.g) either Skywatcher or orion?- which would be better to look at or should i look at all of them?

Do you know any good websites/stores (UK) that i should be looking at?

I’m also unsure about the eyepieces. I know you can get some that come with the bought Telescope, so what eyepieces would you say are absolutely recommended to buy and what do they do? And will any eyepiece fit any telescope?

Again, thank you for your help!

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19 hours ago, cletrac1922 said:

Hi from land down under

Depending on your budget, 10" Skywatcher collapsible dob is weapon of choice

Been other forums recently on this debate

Enjoy your time with us

John

 

 

 

Skywatcher 10 inch Dobson.jpg

I don’t really have a budget, but of course i’m not looking to spend alot as it will be my parents paying for it. 

A 10” sounds great but I am looking for a 6” if you have any to recommend?

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34 minutes ago, Poonam said:

........what is the difference between buying dobsonians from (e.g) either Skywatcher or orion?- which would be better to look at or should i look at all of them?

Do you know any good websites/stores (UK) that i should be looking at?

I’m also unsure about the eyepieces. I know you can get some that come with the bought Telescope, so what eyepieces would you say are absolutely recommended to buy and what do they do? And will any eyepiece fit any telescope?

Without having owned an Orion, I cannot say which is the better, but an 8" Orion vs.8" Skyliner, I would have thought the image would  be almost identical, so your paying any difference for build quality and the brand.

Our Sponsor FLO, First Light Optics is a good call, they'll have 'the' telescope you need, give them a call, they even stock the BST Starguiders, perfect on a scope like mine.

Modern scopes generally accommodate  2" eyepieces with an adaptor to accommodate 1.25" eyepieces, the standard.

What's your location (without providing the address  and door number), folk here can advise on local clubs,  telescope specialists, and/or best viewing sites, but a visit to a local club could  help your decision immensely, and you don't need to join the  local club to enjoy the hobby, you just need to look through someones telescope, of the type your interested in?

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Skywatcher and Orion are the same scopes - both made by Synta in China, they just wear different clothes. But yes, fundamentally the same scope ( I think the Orions are prettier, but they are more expensive too I think?)

just remember to check the size before you buy - I had my heart set on an 8” Dob until I saw the size and realised I had nowhere to put it in my house.

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3 hours ago, Mr niall said:

Skywatcher and Orion are the same scopes - both made by Synta in China, they just wear different clothes. But yes, fundamentally the same scope ( I think the Orions are prettier, but they are more expensive too I think?)

just remember to check the size before you buy - I had my heart set on an 8” Dob until I saw the size and realised I had nowhere to put it in my house.

Wow okay yeah. I just checked sizes. These telescopes are definitely bigger than i thought they would be. Thanks for that advice. 

It is good to know that if i find telescopes from e.g. skywatcher/orion that i can base my final decision on price! Thank you!

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23 hours ago, Charic said:

Without having owned an Orion, I cannot say which is the better, but an 8" Orion vs.8" Skyliner, I would have thought the image would  be almost identical, so your paying any difference for build quality and the brand.

Our Sponsor FLO, First Light Optics is a good call, they'll have 'the' telescope you need, give them a call, they even stock the BST Starguiders, perfect on a scope like mine.

Modern scopes generally accommodate  2" eyepieces with an adaptor to accommodate 1.25" eyepieces, the standard.

What's your location (without providing the address  and door number), folk here can advise on local clubs,  telescope specialists, and/or best viewing sites, but a visit to a local club could  help your decision immensely, and you don't need to join the  local club to enjoy the hobby, you just need to look through someones telescope, of the type your interested in?

Thank you, i think with your help and the internet’s, i have a good idea of what the value of additional eyepieces are. 

I’m in Coventry, West Midlands (UK) so this goes to anyone who reads this- know any clubs/stores in my area?

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I'd go for a 8" rather than a 6", and I'd get a skywatcher one. An 8" dob can be moved in one go for a short diatance. You you don't mind to move the OTA and the base separately, a 10" would be an even better choice in my opinion, possibly a life time telescope.

I'd go for a solid tube for any of these models. They are great scopes! 

I'd also suggest to check the second hand market: SGL classified and astrobuyandsell.

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I think it all depends on what you'd like your telescope to achieve. A 6" will give you nice views of the planets, the moon, and some of the brighter deep sky objects like galaxies, nebulae and star clusters. This is generally considered the ideal scope for someone who is just starting out and would like to know if this is the hobby for them without having to spend too much. If you think you're likely to develop an interest in deep sky objects, then the more aperture the better as these things are very faint and you need the extra inches to tease them out. Going down this road starts to become a balancing act between how much power you would like, how much you're prepared to spend, and how much you can physically lift, as the larger you go the cost and weight dramatically accelerates. I went for the 10" as it's a very nice balance between all three. If you intend to make this a hobby for the long term though, I'd recommend stretching just a little bit further to get an 8" scope as it doesn't cost all that much more, and its significant amount of extra light gathering power means that it could well be the only telescope you'll ever want.

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1 hour ago, Geoff Lister said:

Several years ago, I went for the 250P (10") truss tube Skyliner, with Synscan GOTO, and have no regrets.

and I have the 8" version of the same set-up since a year ago and its been brilliant too :-D

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A 6" dob will be easily portable - is cheap and is a good introduction. 

An 8" dob is still fairly easy to move around and is respectably priced for its performance.

A 10" dob is beginning to get very heavy and you will more than likely have to separate it into its 2 parts to move it and even then negotiating stairs or narrow doors will be difficult. You are also getting into a much bigger financial commitment.

Obviously the bigger the dob the better the performance but moving big ones about can become a pain. Initially you won't mind that but after a year or so a smaller portable scope will probs get used more. I use binoculars more than any of my scopes.

The other thing to consider is that if you enjoy stargazing within 6 months you will start lusting after a bigger scope lol. A 4" increase in mirror size is generally considered a worthwhile improvement. So if you started with a 6" you could move up to a 10" . If you start with 8" or 10" ... then a 12" is massively heavy and a very significant financial outlay and only marginally better than a 10". Have you seen the weight and prices of 14" dobs???!!!

It is all swings and roundabouts really and what is ideal for one might not be quite so good for another.

Skywatcher i believe usually supply a couple of reasonable eyepieces and it is worth getting used to them before thinking about improvements.

The one thing i would definitely recommend though is some sort of red dot finder - maybe a telrad. They make a world of difference, they get you looking at the right star first. Just using a finderscope can be difficult and frustrating - you just don't know where you are looking.

The other recommendation would be the book "Turn left at orion" it is invaluable for a beginner and will even show you what the view through a dob will look like and give you years of things to find and look at. (different types of scopes will produce different orientations of the view which can be initially quite confusing particularly when trying to hop from  one star to another)

Hope this is of some help.

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I just did a quick check on pricing in the UK with FLO, and the 6" is definitely a bargain there compared to the 8" Skywatcher Dob.  It is 73% of the price of the 8" whilst in the states it is 88% of the price at B&H Photo.  The 6" is actually cheaper in the UK after currency conversions whilst the 8" is considerably more expensive than in the US.  At 10", they are more comparable again.  If you were in the states, I'd say grap the 8" for $40 more, but in the UK, I'd say go with the 6" for starters due to price and weight.  It will still show you most planets, the moon, star clusters, and bright nebula just fine.  If you find you've lost interest in it in a year, you're only out £209 if you don't sell it, less if you do.

            FLO (UK)      B&H Photo (USA)

6"           £209                $285.00

8"           £285                $325.00

10"         £429                $545.00

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Personally I don't think you can go far wrong with a Dobson, they are terrific value for money and a great place to start. I own a Celestron 8" SCT with an Equatorial mount so I can use it for photography, but if at a latter date you think you may wish to take it up then you will still have your Dobson for quick and easy set up and even use it while your other scope is in use taking long exposure photographs. There have been so many times that I wished I had a portable scope that was quick and easy to set up plus I could use it while my other one was tied up taking photos. I really don't think you can go wrong, just consider that it isn't all about getting a big aperture, you also have to consider portability and storage as has already been mentioned.  It would be a good idea to visit your local astronomy club and compare the different scopes and weigh up the pros and cons.

I wish you good luck in your new hobby, I am sure you will find it very rewarding.

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3 hours ago, Moonshed said:

.......just consider that it isn't all about getting a big aperture.........

It seem's that everywhere I read, aperture IS  the most important telescope feature, especially for visual observations for two very good reasons?
Firstly its light gathering power. If you need to study  faint distant targets you need a large aperture. Secondly, resolving power. The better the resolution, the finer  the detail?
That said, the physical  size of the scope itself  will determine our limit as the end user, which you have already mentioned.

I would still go for the largest Dobsonian available/affordable.

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One thing to note is that the 6", 8" and 10" dobs from Skywatcher are all basically similar length, they just get fatter!

This is because their focal length is the same at 1200mm, so any calculations regarding magnifications and field of view for each scope will be the same for all three ie a 10mm 50 degree apparent field of view (afov) eyepiece in any of the scopes will give a magnification of x120 and a true field of view of just over 0.4 degrees. That makes comparisons simple.

As the aperture increases, each successive scope will offer better resolution on planets and targets like globular clusters, whilst also giving maintaining a brighter image at the same magnification for deep sky objects (simplified comment before anyone picks me up on it!). This is due to a factor called the exit pupil size but that is probably a subject for another day.

As the aperture increases, the focal ratio which is is calculated as focal length/aperture, decreases. This means the scopes get what is called 'faster'. This photographic term does not really have a relevance for visual observing, but it does mean that the faster the scope, the more sensitive it will be to good collimation. In addition to this, the edge performance of eyepieces is more likely to suffer abberations in the faster 10" scope than the slower 6" scope. Put simply, you will maybe have to spend more money on better eyepieces with the 10" if you want good edge performance.

The 8" is, in many ways, the 'Goldilocks' scope. It is not too big or too small, it is not too heavy or expensive and the focal ratio is not too fast or too slow. That's why it is one of the most popular dobs out there.

That said, I have viewed through a 6" f8 dobsonian and was surprised how nice the views were for such a neat and lightweight scope.

It is best to get something that you are likely to use frequently, and for it not to be too big and heavy so it is too burdensome to take out that often. Only you can really make these decisions but it's best to get an idea of their size before committing.

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8 hours ago, Louis D said:

If you find you've lost interest in it in a year, you're only out £209 if you don't sell it, less if you do.

The 6" Skyliner Dob is an entry level scope, with entry level features, but the features improve with the 8" Skyliner.
The 6" will work, but I would highly recommend the 8" as a first scope.

The 8" scope roughly equates to about .79p a day over one Year? not a great outlay for so much scope, and is the UK's most popular 8" scope! 
I would take the 8" over the 6"

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10 hours ago, Stu said:

As the aperture increases, the focal ratio which is is calculated as focal length/aperture, decreases. This means the scopes get what is called 'faster'. This photographic term does not really have a relevance for visual observing, but it does mean that the faster the scope, the more sensitive it will be to good collimation.

I agree, the term  is often dressed aside for us visual observers, but after reading several articles over the Year's I now often refer to the  scopes speed and focal ratio as a convenient guide to matching/selecting the first suitable  high powered eyepiece.
Matching an eyepiece to the focal focal ratio of the scope, provides  a power/magnification that equals the aperture  of the scope and an exit  pupil around 1mm, suitable and well within the limits of the scope in question.
I agree with everything else you mention, with regards collimation, the faster ratio  the less the tolerance!

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Maybe worth noting that the base for the 8 and 10 inch is the same with just the uprights being slightly further apart. I have the 10 and it easily goes across the back seat of the car with the base in the boot. I have no trouble lugging it about.

Dobs lend themselves to being modded nice and easily to make them more user friendly. Mine has a setting circle and wixey angle gauge witch makes it a push to system when used in conjunction with a good phone app. A lazy susan bearing is a good upgrade and makes the scope move like a dream. Flocking the tube will help with contrast. I fitted a telrad to mine which I use more than my finder which has also been upgraded to a raci finder. You may need to think about dew protection as well. I have a cooling fan on my primary and a resistor on my secondary. A dew shield, and then dew bands for the finder scope and eyepiece and my telrad is heated as well.

If it's just visual then you can't go wrong with a dob. Always go for the most aperture you can afford. And of course you can always stick some tube rings on the ota and stick it on an eq mount if you fancy it in the future.

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