Small refractor advice please.

[Gas_mantle]

Hi all,

I'm returning to astronomy again after about 10yrs of not really doing any 'proper' observing, I've had a life long interest but it's years since I've had sufficient level of interest to justify buying a decent scope etc.

I'm interested in photography so ultimately I'd like to have a go at astrophotography but I appreciate it's not an easy thing to do and so it's something I intend to slowly work towards as my skill and knowledge improves. Since I don't want to keep upgrading equipment I've decided to buy a decent mount from the onset so that it will ultimately serve my astrophotography needs later. I've decided on a Skywatcher NEQ6 pro goto (about £950).

So, that leaves me with the choice of telescope. Although I've had reflectors and refractors in the past my mind is firmly made up to stick with a refractor this time. For photography It's looking like the Skywatcher ED80 is the way forward but I was planning on getting an achromatic with a larger aperture purely for visual work first, then buy an ED80 later.

I had thought of a 150mm achromatic as a purely visual instrument but now I'm wondering if it's worth just buying the ED80 and using it for visual work and not even bothering with a larger aperture achromatic.

I guess what I'm asking is how will an ED80 compare with a larger aperture achromatic at just visual work ? They are both similar priced but obviously one has a larger aperture and the other has better optics. If I just get an ED80 will I find it inadequate for some DSO's ?

Many thanks

Peter.

[Peter Drew]

Peter. The short answer is yes, the ED80 will be inadequate for some DSO's, as will a 6" achromat at a similar price point for some DSO's. The ED80 will still see the majority and it's strength will be its wide field of view. The optical quality of the ED80 will help close the aperture gap between the two where solar system objects are concerned.  

[John]

I like the ED80 scopes and I've owned a few but I do find they "run out of puff" quite quickly when it comes to visual observing and especially of deep sky objects. The 150mm achro will be gathering neariy 4x as much light than the 80mm which, for viewing the deep sky, is a massive advantage.

At the end of the day, 80mm is 80mm regardless of the qualities that the ED glass adds to the colour correction of the scope.

[glynnlondon]

Hi peter it might be worth considering an inexpensive dob for your dso viewing and then the ed frac for AP.

Lots of the good people on here seem to run with both.

[ollypenrice]

Hi peter it might be worth considering an inexpensive dob for your dso viewing and then the ed frac for AP.

Lots of the good people on here seem to run with both.

Exactly. Gven the fact that a Chinese Dob mount is, to all intents and purposes, free why not just buy a visual Dob and keep that separate from your imaging life? Achromats are OK but they are not the refractors that optical junkies (like me  ) get excited about. I'd be inclined to look through a Dob and image through a small refractor. ( In fact that is more or less what we do here. )

Olly

[Gas_mantle]

Hi all,

Many thanks for the replies, the more I think about things more undecided I get !

I take the point about getting a Dob but for some reason I don't like reflectors (I know that doesn't make sense and I'm not sure why but whatever I buy it will be a refractor). Also if I'm spending £950 on a NEQ6 GOTO it makes sense to have a scope that will utilise what is by all accounts a decent mount.

John, what you say about an ED80 'running out of puff' is exactly the concern I have, hence my thinking a larger aperture visual scope maybe a good idea. Although I'm not an astronomy expert I'm not a complete beginner either so I'm worried if I just opt for an ED80 I'll find it's too small for taking a look at a great majority of DSO's.

Is it a case that for serious observers the ED80 is really an imaging scope and of little use visually ?

Cheers

Peter.

[Herbig]

Hi Peter, the ED 80 will give you great wide field views visually but will be disappointing on faint DSOs.

It is fairly good for AP but again will give wide field with a crop or full frame DSLR, for smaller fainter DSOs you'll need a Barlow or dedicated CCD camera and guiding.

If you're getting an NEQ6 you could put a 200 or 250 Newyonian on it but if you won't consider a reflector just get the mount initially and use your camera on it with what ever lenses you have and save up for a nice larger aperture APO refractor.

[Owmuchonomy]

Well I have some empathy. I abstained for a good while but eventually bought a third hand Dob from this forum to complement my frac. I set up my 102 frac for imaging and then either me or my neighbour in parallel will bring out the Dob purely for visual use. It is so quick and simple to do it that way. You'll be underwhelmed looking at all but the brightest DSOs through 80mm I imagine.

[Gas_mantle]

Hi Herbig,

Thanks for your reply.

Funnily enough I have considered the idea of a larger aperture APO. If I didn't bother with either an ED80 or a 150mm achromat that saves close to £1000 which could purchase a larger APO (an ED100 is about £800 or an ED120 is about £1300). Either of those would be nice visual instruments but I'm concerned they will be difficult to use for imaging purposes.

40yrs ago when I bought my first 'proper' scope as a teenager the problem was easy, you had only 2 options, either a 6inch Newtonian or a 3 inch refractor !

Now there's that much to choose from it's a mine field.  Refractor or reflector, maybe Cassegrain, then it's Goto or not Goto, Equatorial or Dobsonsian, Achromat or Apochromat, long focal length or short focal length, Autoguider or no Autoguider !! That's before we get to eyepieces and filters etc

Peter.

[Gas_mantle]

Thanks Owmuchmoney,

It looks like if I do get an ED80 as an imaging instrument I'm really going to have to get something with a larger aperture for visual.

Peter.

[chiltonstar]

My ED80 was bought really as a grab 'n go scope - important for some of us to avoid the LP at our home locations by moving to somewhere darker.......

What is your home sky like Gas_Mantle?

Chris

[Stu]

You could pick up a used 120ED for £750 or £800 which would give you nice visual views.

The 100ED is f9 so probably a bit slow for imaging, whereas the 120 shares an f7.5 ratio with the 80 so with a reducer is better. It would be a little more challenging to guide as it's bigger with longer focal length but still doable I guess.

I would think a combination of an 80ED and 120ED would be reasonably satisfactory given your refractor only desires.

An 80ED could also be packed up used for a decent price.

Stu

Sent from my iPhone using Tapatalk

[Pig]

I prefer my 80mm for visual TBH, even when I had my larger 9.25 SCT DSO's were still smudged fuzzies  they were just larger smudged fuzzies than what the 80mm shows !!!  Hence I think a DOB is the only answer for the visual observing of these targets

I prefer objects such as M42, M45, M11 etc... in the 80mm because you can see them in their full glory and with increased colour.

I don't have a clue about AP I am afraid. However, I have seen some outstanding images from even smaller apertures than 80mm

[Mr Spock]

I find some of the bigger objects are best seen in my 120mm achro at low power. If you have dark skies then a good achro can be very useful.

Bear in mind a large refractor will need a large mount. This is my 120mm on an EQ6 :-

With the attached 22mm T4 Nagler I get x45 and 1.8° - very nice for viewing M45, M42, M31/32 etc

When it comes to imaging then an 80ED is the way to go (plus EQ6 )

[Special K]

HI Peter, I totally agree we are spoiled for choice!  Makes it a nightmare to make a decision sometimes, but folks here are very helpful.  The ED80 combined with EQ6 sounds like a great investment if AP is definitely where you are heading to.

In the interim, for visual use, using the ED80 will be down to what your expectations are and what you are accustomed to seeing with DSO's.  You could be pleasantly surprised by the views, as I was!  However, I moved from a 5.1" newt to the ED80, so don't have a point of reference for the bigger and better stuff there is out there.  My views of M81/M82 and M27 Dumbell are no worse in the ED80, and if anything there is a sharper image.  If you were moving down from a good dob to the ED80 then it's going to annoy with the dim galaxies.  But if you're not going to be hunting the super dim stuff and going for big game, then it could be a good fit for the visual side.  There is also the question of how much weight you want to lug around too. 

As Pig mentions, the color in the ED80 is impressive to my eye too, and the widefields you get are fantastic.  There's a lot of personal preference in all this.   Good luck! 

[Dave In Vermont]

I must agree with Michael above. Looks like a very nice achromatic refractor. I'd like to know the F/ though. Looks like an F/8? As my signature gives away, I have a 127mm F/9.3 achro myself. And the views of brighter objects, such as planets, are jaw-dropping! My first look at Jupiter through it still haunts me today - the perfect black BB of the shadow of a Moon on the cloud-belts is something I'll never forget!

Though, as a confirmed filter-nut, I have many colour-correcting CA filters to use, I've never felt the need to bother using any of them. Though these may cause some to turn up their noses at these achromatic-instruments in favor of the APO's and ED-models out there, it wasn't long ago that these would cost a fortune. If you had a 80mm achromatic-refractor back in the 1970's when I buying my first scope, you were doing very well. A 102mm was about the maximum you'd likely see anywhere. This being the years before the Chinese, and others, made a serious impact on the marketplace.

My new MallinCam video-camera is my learning-project for this Winter - and putting it to task in the Spring. I am looking forward to using it with my 127mm F/9.3, as well as my ST80 F/5. And my other creatures as well. There is room for all of them in my book!

Clear & Dark Skies,

Dave

[Gas_mantle]

Hi all,

Many thanks for all the replies

It's looking like an ED80 satisfies the imaging problem, now I've just got to decide what to opt for as a visual instrument.

Chiltonstar, were I live has largely unobstructed views of the sky and although there is some light pollution it's not the worst I've seen. Unfortunately there is a street lamp at the southern aspect although it's not right next to my garden. I realise at some point filters will be a good investment   (I guess that will be another minefied of choice  ).

Luckily my observing site is literally a few yards from my door so although I'll be setting up equipment alone I don't need to worry about moving delicate items over longer distances.

Thanks

Peter.

[Owmuchonomy]

Thanks Owmuchmoney,

It looks like if I do get an ED80 as an imaging instrument I'm really going to have to get something with a larger aperture for visual.

Peter.

You are welcome to review my scopes first hand if you fancy. I live between Harrogate and Ripon. Send a PM if you want.

[bomberbaz]

http://www.teleskop-express.de/shop/product_info.php/language/en/info/p998_Celestron-C6-SC-XLT---150-1500mm-Schmidt-Cassegrain-Tubus.html

What's about a cassegrain ota for visual. Easy for transportation purposes and when you come to eyepieces you won't end up shelling out a fortune on eyepieces due to the longer more forgiving focal length. Just a thought!

[Gas_mantle]

http://www.teleskop-express.de/shop/product_info.php/language/en/info/p998_Celestron-C6-SC-XLT---150-1500mm-Schmidt-Cassegrain-Tubus.html

What's about a cassegrain ota for visual. Easy for transportation purposes and when you come to eyepieces you won't end up shelling out a fortune on eyepieces due to the longer more forgiving focal length. Just a thought!

Hi Steve,

I must admit I never really thought about buying a Cassegrain for visual observing till you mentioned it but it's something I'll look into.

Having had a break from astronomy for a number of years I'm a little bit out of touch with Cassegrains, when I last used a scope they weren't really available to amateurs on a budget so I kind of overlooked them.. I'll have a read up about them over the next week or 2 and see what's available etc.

So I guess the next question is, assuming I buy an NEQ6 Goto with a view to buying an ED80 imaging scope next year what Cassegrain would people recommend as a visual scope costing upto about £800 ?

I realise different scopes are better suited to viewing different objects but I'm not in position to have a different scope for everything so I'm looking at something that will give me pleasing results at a variety of targets. I don't specialise in one particular field of observing so a decent all rounder would be useful.

How does a small Cassegrain compare to a 150mm achromat refractor ?

Many thanks

Peter.

[bomberbaz]

Hi Steve,

I must admit I never really thought about buying a Cassegrain for visual observing till you mentioned it but it's something I'll look into.

Having had a break from astronomy for a number of years I'm a little bit out of touch with Cassegrains, when I last used a scope they weren't really available to amateurs on a budget so I kind of overlooked them.. I'll have a read up about them over the next week or 2 and see what's available etc.

So I guess the next question is, assuming I buy an NEQ6 Goto with a view to buying an ED80 imaging scope next year what Cassegrain would people recommend as a visual scope costing upto about £800 ?

I realise different scopes are better suited to viewing different objects but I'm not in position to have a different scope for everything so I'm looking at something that will give me pleasing results at a variety of targets. I don't specialise in one particular field of observing so a decent all rounder would be useful.

How does a small Cassegrain compare to a 150mm achromat refractor ?

Many thanks

Peter.

I will leave someone else to answer this one Peter as iI am not very up on what the best is myself tbh.