Yet another new telescope question/help !

[Ptarmigan]

After many years of happy binocular viewing I am contemplating buying a telescope.
(shock horror, debit card looks nervous and hides in a corner!)
Two candidates are Celestron Nexstar 8SE and Skywatcer 300pGOTO
The 8SE wins on portability, the 300 wins on aperture
(! quite a dilemma !)

I have a question about 1.25" or 2" eyepieces :-

a ) The 8SE comes with a 1.25" diagonal and only 1 eyepiece, 25mm (giving about 80x)
so before I would go spending on extra eyepieces should I decide if they (or which) need to be 2" ?
What is needed to convert the 8SE to 2" (apart from a 2" diagonal of course !), is this where the 'visual back' thingies come into play ?

b ) The 300 comes with two 1.25"eps, 10mm and 25mm (giving 60x and 150x) so that should be ok for starters
but a similar decision on more would no doubt be needed at some time in the future, although having got 2 already at 1.25" would I continue to build up a stable of 1.25s ?

For the 8SE I am thinking that I would want 1 or 2 in the region of 6 to12mm (for planetary etc) and they can be 1.25" being higher mag.
but what of the range 15 to err 35mm? for the wider field, should they be 2" ?

My brain cell is starting to hurt !!!

[jambouk]

The long focal length of the SCT will probably mean you are unlikely to get great FoV benefits from 2" eye pieces over 1.25" ones

Put the various scopes / eye pieces into this web page to get a rough idea of how things will look.

http://www.12dstring.me.uk/fov.htm

Jd

[Ptarmigan]

The long focal length of the SCT will probably mean you are unlikely to get great FoV benefits from 2" eye pieces over 1.25" ones

Thanks Jd, good point ! That could save a bunch of £s

Not sure about the link and cameras, that's a whole different ball game.

I think for the timebeing I wll remain a visual observer - although a new dslr may be on the cards for other reasons so may get attached to the telescope for experimental porpoises

[jambouk]

Click "switch to visual" and it shows you visual, and instead of selecting cameras you select specific eye pieces.

Jd

[brantuk]

12Dstring gives you fov for "camera chips" and also for "observing" - just gotta make sure you pick the right one.

[Ags]

On the contrary, the narrow FOV of the SCT means you really need to use widefield 2" eyepieces for the larger DSOs... even with the widest 2" eyepiece you will only have 1.4 degrees.

Whereas you can buy a cheap 40mm 70 degree EP for the SCT, to get the maximum field in the 300mm, you need to get much more expensive 24mm 82 degree EP, due to lower contrast and dimmer image from longer EPS in the Dob.

[Tiny Small]

If you are going for visual, I would get a 300mm Dob and stick some of these in it: http://www.firstlightoptics.com/skywatcher-eyepieces/sky-watcher-swa-70-eyepieces.html They're brilliant, especially for the money.

[John]

I've recently had a Celestron 8SE and currently have a 12" dobsonian. 

Both great scopes of their type but difficult to compare directly because they are such different approaches. You could argue that if you are in the market for one, you would not be interested in the other, or vice versa !

Alternatively you could argue for owning both as they have complimentary strengths and weaknesses.

The SCT would be great for high planetary and lunar viewing and it would do OK on most deep sky objects. The 12" scope swallows a lot more light so it will show deep sky objects quite a bit better and will still impress on the moon and planets.

The 8SE will perform better with low to medium cost eyepieces than the 12" scope will.

[Ptarmigan]

>Jd & Brant

Doh !! Thanks, found it ! Either I am as blind as a bat or I need to email David to put the switch up the top by the camera(/eyepiece) label !

I just put in SE8 and 8mm on M13 - - eeek, gosh !

Thanks for all your replies everyone, lots to digest !

> John "You could argue that if you are in the market for one, you would not be interested in the other, or vice versa " etc etc

Yes, hence my !dilemma! and you may be nearer the answer than realised , , , time for an anecdote :-

Originally I was thinking either 8SE (for its portability) OR a 14" Skywatcher manual (notGOTO) for similar money but the 14" would get less use (mostly just outside the front door) and might even need its own semi-permanent shelter.

When I outlined the dilemma to OH she suggested to get both !

Back to thinking , , ,

[Ptarmigan]

I've recently had a Celestron 8SE and currently have a 12" dobsonian.

Ah, I feel the need for an inquisition

As Cilla might have said

"Candidate No1 (8SE) Did you feel the need to switch from 1.25 to a big one ?"

"Candidate No2 (300) Did you feel the need for 2" "

or vice versa

LOL! but seriously,

would I just plod on with all 1.25" to begin with and not worry and leave the matter of 2" to future experience/expenditure rather than trying to future-proof at the start ?

Ags >

FOV of the SCT means you really need to use widefield 2" eyepieces for the larger DSOs

Above what mm would the 2" become desirable would you say ?

[bomberbaz]

Having owned both I vote for the 300p.

As per John the 8se had its strong points but the main ones to me were is more portable and is more forgiving on lower cost eyepieces as already mentioned.

the 300p is not thAat much of an issue transporting to me although I do go to the gym regularly but the main thing to me are the views, far better for detail and my only regret is I didnt get the 350, hehe

[scarp15]

Which ever of the two scopes you choose, it will complement your binoculars. Concerning the diagonal on the 8" SCT, most users tend to ditch this for a 2" diagonal (with a 1.25" adapter as standard) so you can use low power 2" wide field e.ps in additional to medium and high 1.25" eps.  

For eyepieces, take you time in selecting, becoming knowledgeable and costing up options, as this can take time.

[brantuk]

"When I outlined the dilemma to OH she suggested to get both !"

Ohhhh now you're onto a winner there. That's a woman worth listening to - and taking advantage of lol.

(You've also got to spoil her a bit now and again - but for the superb advice she's well worth it)

[John]

Ah, I feel the need for an inquisition

As Cilla might have said

"Candidate No1 (8SE) Did you feel the need to switch from 1.25 to a big one ?"

"Candidate No2 (300) Did you feel the need for 2" "

or vice versa

LOL! but seriously,

would I just plod on with all 1.25" to begin with and not worry and leave the matter of 2" to future experience/expenditure rather than trying to future-proof at the start ?

Ags >

Above what mm would the 2" become desirable would you say ?

I've had a mix of 1.25" and 2" eyepieces for some time now. As someone who got a taste for wide angle views some time back I found the 2" format was required in the focal lengths longer than 20mm to show the wide views I like so much.

It's entirely possible to just stick to 1.25" eyepieces though. Most deep sky objects will fit into a 1 degree true field of view.

One of the upsides of the 8SE is that it's just about the most portable and compact 8" scope I've used, including 8" dobsonians. If storage space is at a premium and / or you need to move the scope some distance to your observing spot the size and weight could be very handy indeed.

A 12" dobsonian is a much larger proposition but you probably know that from the photos of them that have been posted on here.

[Ptarmigan]

I do go to the gym regularly ,,

I didnt get the 350, hehe

I dont ! I am a 5'6" 10st weakling that has trouble carrying a 25kg sack of chicken feed !

(which I wouldnt cry over if I dropped it ! but a telescope is summat else !!)

Re the 350, see my anecdote to John above

But actually folks, my bad in the orig post, the question (at this stage !) is not so much which of the two candidates to choose (that will come later) but which would benifit most / need consideration of / need most expenditure on / the eyepiece trail , if you see what I mean !!! , as part of the pros and cons of all other things to be considered later , like portability and light grasp.

I can see that the 300 would need a new focuser ( by all accounts that would be a good thing anyway ) but it starts with two eps that might need to be thrown away whereas the 8SE only has one that might languish in the spares box

but I have no idea what goes on the back of the 8SE to be considered in the matter of 2"ers.

etc.

I hate shopping by internet, the vendor pages never answer my questions, Skywatcher dont even tell me weights for their oh-so portable Dobs ! How daft is that ??

Scarp >

Which ever of the two scopes you choose, it will complement your binoculars.

Yep, that is where I started : something to quickly grab-an-go betwixt rain and clouds,

at the mo. I think the 8SE is the way to go for that.

[Ptarmigan]

That's a woman worth listening to - and taking advantage of lol.

(You've also got to spoil her a bit now and again

I do I do on all three counts

She was one of my better decisions in life

John >

8SE is that it's just about the most portable and compact 8" scope I've used, including 8" dobsonians.

etc.

Thanks John, a valued opinion, I am liking what I hear

Storage is not a prob. (getting it in and out of storage could be!) but I live on a hill and most parts of the garden (except just outside the front door) involve up/down steps or a long slope to dodge the trees etc. !

I think the 8SE would be a quick grab and go whereas the 300Dob would be in two parts and would need a sharp weather eye , , ,

[Tiny Small]

Why would it need a new focuser? The skywatcher crayfords are perfectly reasonable. If you are not happy at a later date you can get an upgrade mod for much less than a new focuser. Having just installed this; http://www.365astronomy.com/dual-speed-110-microfocus-upgrade-kit-for-skywatcher-crayford-focusers-p-2484.html, I can say that my focuser has now gone from perfectly reasonable to very good indeed.

As an owner of the 250p dob, I can say this about them:

They are accommodating of cheaper EPs. I made do with the stock ones for a while and they gave pretty decent views. Plossls gave better and 2" EPs give great views. Even using standard issue Super MAs, you will get good views. As regards to weight, it is sort of irrelevant as you should be moving the base and OTA separately (base first then OTA). I don't know about the 12" but the 10 fits into a hatchback, either putting the rear seats down or laying the OTA across the back seat with the base in the boot (or on passenger seat if you have a very small hatchback). Moving the base and OTA separately like this means that even my wife can manage it, and she is a 5'2" weakling.

I don't know a thing about the other scope, but don't discount dobs out of hand. The extra aperture really is worth it, they are no more difficult to transport by car or by foot over short distances than any other scope and above all else, they are simple. This is worth so much by its self. Plonk it on the floor and start observing immediately. When cooled, push the mag as high as you can or as low and wide as you like. 

[YKSE]

The weight for 12" OTA are usually around 20kg, and rockbox another near 20kg. Orion Optics' OTA is lighter, about 14 to 16 kg depending on focal ratio.

http://www.teleskop-express.de/shop/product_info.php/info/p2492_Skywatcher-Skyliner-300P-FlexTube---12--Dob-Truss-Design.html

http://www.orionoptics.co.uk/VX/vxspecifications.html

[bomberbaz]

I think the 8SE would be a quick grab and go whereas the 300Dob would be in two parts and would need a sharp weather eye , , ,

The 8SE is not what I would call a quick grab n go but you can leave it setup and carry it in and out of the house fully set to go through double doors as I did.

in terms of cost of eyepieeces and other extras your potentially looking at a larger diagonal for 2" eyepieces, decent ones are available at around 70 pounds or so, you can o/c pay more. Also a power pack and cable. Also dew shield but you can make one yourself easily and cheaply. Eyepieces are your big saver, lower costing eyepieces are very forgiving in the F10 8SE and my fave in the scope was a 40mm william optics swan eyepiece for giving that space wzlk emersed view, superb.

Also other mid range eyepieces also give great views without busting the bank, I used baader hyperions and celestron xcels. Although I believe there are many more that would be perfectly suitable. I liked the look of tjose skywatcher ep, s.

[Ptarmigan]

Why would it need a new focuser?

or by foot over short distances

To accomodate a 2" eyepiece, or did I miss something ?

, , , ah yes, to get to the eastern sky (the other side of my trees) involves two flights of steps and a 100yd walk

down the drive and up the lane (private so no traffic worries) to one of my alternate sites.

YKSE >

excellent info, that is what I was guestimating for a 12", thank you.

the only remaining prob on the Dob front is if the GOTO would need two persons ( some sort of dovetail may be involved on one of the pivots ??) whereas the manual looks to be a 'drop-into-place' onto two pairs of rollers/pivots, which is more probable a one man job ??

Still investigating thatall.

[bomberbaz]

The 300p goto is a 1 man job, its simple, trust me.

[Tiny Small]

To accomodate a 2" eyepiece, or did I miss something ?

, , , ah yes, to get to the eastern sky (the other side of my trees) involves two flights of steps and a 100yd walk

down the drive and up the lane (private so no traffic worries) to one of my alternate sites.

They come with a 2" native focuser along with a 1 1/14" adapter.

[Ptarmigan]

They come with a 2" native focuser along with a 1 1/14" adapter.

Ah ! Thank you, great, that is one thing less to worry about !

I got confused somewhere along the line, so much info to get into my little brain cell

[John]

To accomodate a 2" eyepiece, or did I miss something ?

, , , ah yes, to get to the eastern sky (the other side of my trees) involves two flights of steps and a 100yd walk

down the drive and up the lane (private so no traffic worries) to one of my alternate sites.

The standard Skywatcher focuser will take 2" eyepieces as well as 1.25" ones. It's not a bad focuser in my opinion but then I'm not that fussy on focusers.

My 12" dob is about as light as one of this aperture can get (around 26kg in total) but I can't carry it more than a few feet in one piece and I don't think I'd fancy your 2 flights of steps and 100 yards with it in two sections either to be honest. The furthest mine goes is out of the french windows and onto the lawn, about 4 yards, and I put the base out first then lift the scope tube out and onto it.

You can put wheels and handles on these things though and that would make greater distances more feasible, with care.

[Tiny Small]

You can put wheels and handles on these things though and that would make greater distances more feasible, with care.

I have a dolly that I bought for a video camera tripod (yes... a video camera... I work alongside people who are too young to remember those!) years ago. The little feet on the dob slot nicely into the foot clamps and the wheels are nice and big with brakes. As you say, with careful guidance this makes much larger distances an easy affair. Any trolley or wheeled platform will do, but if you need to move up and down hills, something like this would be perfect; http://www.machinemart.co.uk/shop/product/details/cst4b-2-in-1-sack-truck?da=1&TC=SRC-sack%20trolley

I have one and it's useful for loads of stuff. Very sturdy too.