looking for the most simple refractor telescope

[Chris]

The eq5 pro is equatorial mount which is better suited to long exposure photography. you can allign these mounts to the pole star so you don't get field rotation on images. They also have stronger more accurate drives for better imaging results.

The az mount has the same goto system and will find and track objects the same as the eq5 pro, however, the mount moves simply up down left right to do so which is much more suited to visual work.

The payload for the eq5 will be greater but the az will take a 5 inch maksutov or 4 inch short tube refractor.

[wuthton]

Az is simple to use and setup, Eq is not. Bottom line.

[Tiny Small]

I own a 10 inch reflector (dob) and a 4 inch refractor for visual observing. The refractor goes in a large daysack when I want to go to a mates for a beer. If I am observing at home or driving somewhere, the 10 inch dob ALWAYS wins out. You can see pretty much everything in it. You can resolve stars in the cores of globular clusters with it as well as getting great views of all the nebuleae and galaxies in the visible light spectrum. Set up is as easy as put it on the floor and point it. Thats it. New they are considerably less than your budget and I got mine second hand for £250. By comparison, the refractor is rubbish. It gives nice views of the moon and open clusters, but that's it. Also, even the simple alt/az mount is more complicated to setup than a dob base. A larger refractor would be nice, but still not as nice as a big 10 inch mirror. Also, I love difraction spikes on bright stars. They make things look just a little more special.

[jestar]

Thank you Wuthon, the AZ is also a lot less expensive.

Hi Starfox, what is a short refactor ?

[Chris]

Thank you Wuthon, the AZ is also a lot less expensive.

Hi Starfox, what is a short refactor ?

Hi, a short tube refractor is one with a short focal length and fast focal ratio. Focal ratio is focal length divided by the aperture so if you have a 100mm objective lens and a 1000mm focal length then the scope is f/10. F/10 is around average for an achromatic refractor and shows moderate chromatic aberration, as the focal ratio gets faster the doublet lens cannot merge the 3 primary wavelengths of light as well thus you get purple fringing known as chromatic aberration. going the other way a scope with a focal ratio of 15 (f/15) will have virtually no chomatic aberration but the scope will be very long in physical length. ED (semi apo) or apochromatic refractors use exotic glass and sometimes 3 or 4 lenses to help merge all wavelengths of light at exactly the same point so ED and Apo refractors can have shorter tubes without the purple fringing appearing on brighter objects. 

So in a nut shell its a refractor with a short tube, but unless its an expensive apo the short tube will come with the price of chromatic aberration. Both Celestron and Skywatcher do an AZ goto with a short tube f/5 achro refractor which would show fairly bad chromatic aberration on the planets and the Moon. the mount unfortunately wouldn't cope with a tube much longer though due to weight and moment of inertia which is why they aren't sold with large long refractors.

hope that helps.

Chris

[jestar]

OK Chris, So the az goto would be ok with the equinox 100ed as it has focal length of 900mm, right?

[dweller25]

OK Chris, So the az goto would be ok with the equinox 100ed as it has focal length of 900mm, right?

No - it's not rigid enough to support a 900mm focal length scope

[L8-Nite]

...........Granny has always been vaguey interested, but no more than most people so if she's going to sit on the garage roof on a cold clear night she wants the best equipment she can afford, on top of which she has been reliably informed that she can expect up to 70% of the cost back if she sells the equipment.

So........ "looking for the most simple refractor telescope" 

 Consider a  Zeiss "Telementor" refractor.  (my avatar)

Well worth looking for on the used market.  

[Chris]

OK Chris, So the az goto would be ok with the equinox 100ed as it has focal length of 900mm, right?

Sorry, I think this might be pushing the limits of the az goto?

Celestron use a 100mm f/5 scope on these mounts which would havea focal length of 500mm. You can probably push slightly beyond this but the scope you suggest is almost double so I think this would be too much. an ED80 would work fine though I'm sure

Chris

[Chris]

I know you have you heart set on a refractor but this is another reason why the maks win on these mounts. with a Maksutov the focal length is folded over twice so you can have a very long focal length scope compacted into very short dimensions. This can then easily be handled by both users and light weight mounts such as the az goto.

Sorry thats the last time I mention Maksutov's I promise

[nightfisher]

 Consider a  Zeiss "Telementor" refractor.  (my avatar)

Well worth looking for on the used market.  

Nice, i have the swift 839 and its rumored to match the telementor 

[Moonshane]

what about http://www.firstlightoptics.com/heritage/skywatcher-heritage-90-virtuoso.html

this will provide good views of moon and main planets as well as the larger and brighter DSOs. plus it tracks. there's a 114mm Newt version too.

one advantage of this is that you can just put it on something for the little one which can eventually be a tripod as he grows.

for a child this young it seems ideal on the assumption you can (and will want to) hep with setting up/teaching him how to work it.

it has a little bit of technology but not overkill.

[L8-Nite]

The Telementor was designed as a teaching telescope, a "School Scope". I've never seen anything that can match the optical and mechanical quality in any of today's comparable mass market scopes.  Jester states that he was looking for a "starter" telescope, and had his heart set on a refractor, "even if it was a mistake". A Telementor kit would fall into his budget, and I'm confident it will be no mistake, on the contrary, I find ours to be a lifetime scope; even though I have a considerable investment in others.

Edit: Take time do the research, you will be glad you did.  

[cutepetgroomer]

I own nothing but refractors. I love them and they are all altaz mounts.

[jestar]

Thanks everybody,

I have a few free days next week so, armed with all my newly aquired knowledge, I am off to the big smoke (Manchester not London). I'll leave my newbie bucket at home and try and make a few intelegent remarks.

Does anyone know the best places to look.

[dweller25]

Hello Jetstar,

Opticstar just outside Manchester are very good......

http://www.opticstar.com/Run/Root/Root-Home.asp

Also I live just North of Manchester in Ramsbottom so you could pop in one evening if you wanted - I have a 4" refractor, various EQ mounts and a Dobsonian that you could look at.

[jestar]

Hi,

Can anyone tell me how the EQ5 synscan goto mount stacks up against the EQ3.

[ronin]

A lot more stable and solid.

The EQ5 is a good all round mount that within reason will do everything pretty well.

The Synscan system/software is the same - not sure about the motors but I thing they are beefier then the EQ3.

[Moonshane]

but surely a three year old child will struggle to reach the eyepiece?

[glynnlondon]

Hi Jestar ,

Thats a good shout by david about opiticstar. You will be able to size up the various telescopes and mounts and their weights,

I have a small newt on an eq2 mount and that is fairly heavy and awkward to move.

Also dobs and newts require collimating and that is tricky for a beginner.

As a newbie myself its taken me 2 months to collimate it properly , tho im a bit of a div with things like that and others pick it up quicker.

Felt like sticking my head in a bucket looking at allen keys and cheshire collimation pieces.

[nicks90]

Still think you're well off the right track to be considering a frac on an EQ mount...

Unless you are getting in to the realms of astrophotography, then an eq mount is just an unnecessary complication, expense and weight.

A 7 year old WILL struggle to get to the eyepiece of a long frac - period. I have a 7 year old and the only scope she is comfortable using s my 12" dobsonian ( stands on a small caravan step). She does own and use a little 70mm f5 frac on a camera tripod, but constantly asks me to alter the tripod height up and down to keep the eyepiece at a sensible height for her, bending down to the ep means she gets bored in seconds! Therefore I spend half my time altering the tripod up and down so the ep stays the same height or she just looks at stuff at that specific elevation where the ep is comfy for her. And that's a SHORT refractor! Put a 600mm+ frac in the equation and its just got a whole lot worse!!!

A MAK or SCT will give you more aperture for similar money (and aperture does rule!), is much easier on eyepieces as they are longer F ratio, does not suffer horrible colour fringing and are very very short! On a goto alt/az mount, the ep might move only 4" inches vertically meaning very easy viewing for everyone, and the scope is extremely short meaning good stability on the mount.