Questions regarding first scope

[Blackcat XIII]

Hey guys/girls, :D

I have been following these forums for a while and trying to gather as much info as I can about purchasing my first scope. One thing I have come to realize is that aperture rules and the best bang for your buck is a dobsonian.

I was looking at purchasing an 8 inch dobsonian, however I am wondering If I should go for the Celestron NexStar 6SE. I really like the idea of having the ability to take photos of the Moon/planets and some DSO's.

I have a few questions about the 6SE. Can you use it without power? I don't want to rely on batteries to keep it going, however I have noticed you can get some kind of battery pack instead...how much do they go for?

I live in an urban area with plenty of light pollution, what will the difference be between an 8 inch dob and a 6SE? I understand the 8 inch will take in more light but will the Cassegrain optics make up the difference with regards to sharpness and contrast?

I don't want to be spending more than $1599 on my first scope. So I understand that if I was to purchase the 6SE I would be using it as is for a while before I go out and spend money on EP's etc...

I'm guessing my other option is to by the dob and later on buy a mount that can support it for AP?

Any thoughts would be appreciated.

Celestron 6SE (http://www.ozscopes.com.au/cassegrain-telescope-celestron-nexstar-6-se.html) $1599
8 inch Dob from Bintel (http://www.bintel.com.au/Telescopes/Dobsonian/Bintel-BT202-B-8--Dobsonian/72/productview.aspx) $499

Thanks in advance,

Blackcat

[barx1963]

Hi Blackcat
As other will attest I am a great fan of dobs. I did a lot of research before buying my dob and remain convinced they give great value for money.
You have asked some really good questions that indicate that you have done some research so I will try to answer as best I can

As far as taking photos is concerned you can take photos of some brighter objects EG moon and planets with the SE, and for that matter with the dob, but don't expect startling results. if using a DSLR, the afocal method is probably the way to go. If you want to attach the camera you would need at planetary camera or webcam style. For DSO imaging neither scope is really suitable.

Not sure about the operating the SE without power. Bintel do a power solution ( see http://www.bintel.com.au/Accessories/Power-Supplies/Bintel-12V--br-DC-Solution/933/productview.aspx ) which I use for the dew protection on my scope and it is simple and reliable.

In light polluted areas, aperture is usually a good solution, which leans towards the dob. Contrast is mainly affected by the centre obstruction which tends to be larger in the Cassegrain scopes. Sharpness is more to do with the eyepieces. Both scopes even with cheap EPs will be fairly sharp in centre. But you will notice that they get worse towards the edge of the field. Good quality EPs will give wider sharper fields.
So again a dob will leave you with $$$ to spare on those EPs.

In the future as you said the dob can be adopted as an imaging scope, so that is a plan.

Good luck with your decision

Malcolm

[Blackcat XIII]

Excellent, thanks for the info. I will continue my research before I go putting any money towards a scope.

Blackcat

[andyc]

Hi Blackcat, my suggestion would also be to go for the Dob. You can then easily afford a decent EP or two (with cash to spare), and if you're in an urban area a light pollution filter would serve you really well for picking out deep sky objects, especially all those juicy southern nebulae. Spending quality time under the stars learning to find objects with a Dob will also give you a much greater 'feel' for the sky than using a computer to find objects for you. And a great many more objects will be within reach too with 8" compared to 6"! And you'll spend almost no time setting your telescope up too when it's observing time.

The flip side is I know little about astrophotography and would defer to others on that. If that's your goal, then different advice might be better! I like finding the clusters, nebulae and galaxies even if I have to do it from a Melbourne sky, so I am biased towards the Dob for that.
andy

[jjjnettie]

Hi, welcome to IIS.
You will tire of a 6" scope a lot quicker than an 8". For wide bright views, I'd go for the dob.
You can still take quite reasonable images of the Moon, Sun (properly filtered of course) and brighter planets through it. And if you find down the track that the imaging bug bit you hard, you can remount the scope on an equatorial mount and go from there.
Dip your toes in first, go to a few star parties too, see what others are using and get their opinions too.
You can't go wrong with the dob.

[Blackcat XIII]

Thanks for all the great replies!

Any Recommendations on EP's for an 8 inch dob? (1200mm (f/6))

The EP's it comes with from Bintel are: Quality 26mm (2") Fully Multi Coated Eyepiece, 15mm and 9mm Fully Multi Coated Plossl Eyepieces.

Out of curiosity how much are the mounts that can hold an 8 inch dob for AP? Not that I plan on getting one anytime soon.

Blackcat

[bmitchell82]

you could get away with a HEQ5 but ide be saying more like a NEQ6Pro they are somewhere around the 1400 - 1800 respectively.

For a start the standard eyepieces are not bad at all. use these untill you figure out what it is you want to look at and what the need you find that you have! this will stop you wasting your money.

My personal pref i wouldn't bother with the 6" as you can get a goto tracking 10" for the same price here (http://www.andrewscom.com.au/site-section-10.htm). more aperature than both for the same kind of pricing $1500. Just be aware that just because the tracking goto dobs are tracking and go to that doesn't make them good for astrophotography, for planetary it would be a good little combo with a 5x power mate and something similar to a DMK astro webcam.

I have meade series 5000 ep's they are quite nice but i will be the first to say im not a visual person im into astrophotography, that being said my 254 newt was once a 10" dobsonian and i still use the dobsonian base to store the OTA.

Good luck

[barx1963]

You will find that of the EPs that come with the scope the 26mm will be the one you use the most. The 15mm a bit and the 9mm will be hard to use as it will have a small exit pupil and small field of view and short eye relief. I keep a 10mm plossl that came with my first scope on hand to pop in to remind myself how nice my good EPs are!

IMHO Televue are the EPs of choice. I would go something a bit different to the 26mm initially. That will give you 46x power (1200mm / 26 =46.15)
so you will need a higher power EP around the 12-15mm mark. The 13mm Nagler will give you 92x (twice the power) and is a superb item if you can spare $299 (Bintels price) I have one and it is the shizzle!
The one disadvantage is the eyerelief is not startling at 12mm so if you wear glasses it may take a little getting used to, but I use glasses and have had no problems.
The best strategy is hold on to your cash until you have a bit of experience under your belt and have a clearer idea of what you need. Even better is to get to a club night or observing session and see what others are using and try out a few EPs for yourself.
Whereabouts are you so we can see if any clubs nearby?

Malcolm

[Screwdriverone]

Hi Blackcat,

I have an 8" reflector (not a dob) on an HEQ5 Pro and this is an awesome visual/AP rig.

Andrews has this for :

BD 203 x 1000 Newt. w/HEQ5PRO package$1599

Although they shut on Wed 21st Dec.....bummer

However, this scope is great for visual, tracks beautifully for AP (although needs a slight mirror screw mod to get the camera to focus with an MPCC (coma corrector) in line) but generally is around your budget, but for me is the perfect blend for occasional AP as well as planetary with a webcam and visual just like a dob will give.

Keeping costs low initially with a dob is a great idea however, simply because they resell well if you dont really get into it and as discussed can be converted to an HEQ5 or HEQ6 quite easily later on....

Dob use is a doddle, take it out, plonk it down and point it anywhere or simply cruise around and see what is there. A goto like mine requires alignment and a battery pack and is more fiddly, however if you are a techy sort of person, its really easy.

Start small with the dob, just keep this scope in mind as its great value for money.

If you want to see some of the pics I have taken, click here (http://www.iceinspace.com.au/forum/showthread.php?t=82662) for a solar pic, here (http://www.iceinspace.com.au/forum/showthread.php?t=82661) for a Jupiter shot, here (http://www.iceinspace.com.au/forum/showthread.php?t=63622&highlight=lagoon) for a Lagoon Nebula Shot, here (http://www.iceinspace.com.au/forum/showthread.php?t=63634&highlight=m22) for M20 Trifid Nebula, here (http://www.iceinspace.com.au/forum/showthread.php?t=63635&highlight=m22) for M22 Globular Cluster and here (http://www.iceinspace.com.au/forum/attachment_browse.php?a=79187) for a picture of the scope itself.

Gratuitous self promotion intended.....:P

Cheers

Chris

[barx1963]

I would agree with Chris that an 8" Newt mounted on an HEQ5 would be a good all round scope for visual and AP except for:
- the eyepiece will often be in difficult positions requiring the tube to be rotated
- you have to learn polar alignment
- the movement is not intuitive like an alt az or dob mount

Malcolm

[jjjnettie]

The eye pieces they supply with the scope are quite good.
You will definitely want to buy a 2x barlow lens. This will double the focal length of all your eyepieces. Great for observing the planets.
Hmmm that package that Chris mentioned, the 8" on HEQ5Pro is pretty good.

[Blackcat XIII]

Thanks a lot for all the info guys, It has helped me weigh up my options. I think I'm leaning towards a dobsonian, as I will have left over $$$ to spend on other accessories if needed.

Hopefully this post helps out others in a similar situation.

Looking forward to clear skies and epic views of the night sky. :eyepop:

By the way Chris, those pics are awesome. Something to strive for in the future.

Blackcat

[ZeroID]

Hi BlackCat, My first EP buys for both my 4.5" and then later the 10" scopes was a 20mm GSO Superview and a 2 x Barlow. I quickly added the GSO SV 15mm as well. Reason: reasonably priced, only $49 at the time and they gave a nice wide field of view, 68 degrees I think and good eye relief. They are still my most used EPs as they give abig enough field to see your target and it's surrounds and with the Barlow you can then double the mag and enjoy some reasonable closeups.

I am not saying they are the best EP's in the world, you can spend hundreds, even thousands of $$ in some cases on really good glass but they are excellent beginners EPs and the two sizes give a good range of views.
I have obviously acquired a few more since these first two but these are still working for me visually.

Have to concur with earlier posters here as well, the DOB 8" or 10" is the best starting point for most beginners. Even if you decide to move to other hardware later picking up a good second hand Dob which can one day be sold on to finance your next acquisition or as in my case rebuilt to a new configuration.
The wee 6" while cute, will lack any real punch visually. Handy as a 'Grab & Go' for travel or between clouds maybe but not big enough to explore the skies seriously.

Cheers
Brent

[andyc]

I have a selection of the Meade Series 4000 Plossls that I used with an 8 1/2" f/6 Dob back in Scotland. They are still serving me after nearly 20 years, and give quite satisfying views, though dew and use has made a mess of the coatings. New ones are a bargain at $59 from Bintel (I paid ~£100 in the 1990s for mine!), and something like that is probably not a bad 'basic' eyepiece. Seeing as my old scope is close in spec to the one you're considering, here's how I use my eyepieces most:

In dark skies, when the exit pupil is big enough, a 32mm gives great wide-field views, but to get value for light, you need your eye's pupil to open up to >5mm, which it may not do under urban skies. The standard 26mm, if it gives reasonable views, would be fine for this. Otherwise, the 12.4mm was a good medium power, with ~1/2 degree field. I have a 4.7mm ultra-wide angle but I'm not so fond of the view so wide you can't see the field stop, was never quite happy with this EP. I prefer using a Barlow with the 12.4mm, which gave me ~200x, decent for good views of Mars, Jupiter and Saturn, or for close-ups of globulars and planetaries. So my most common focal lengths would be 20/32mm low power depending on sky darkness and eye pupil size, then 12mm for medium power and somthing near 5-6mm for high power.

I have no experience of the top premium eyepieces like Televues or of 2" EP's that your telescope could accept, but they can probably wait until you're more familiar with whatever scope you get.

[Blackcat XIII]

Thanks for the info regarding the EP's. :thumbsup:

I ended up getting my 8 inch dob and definitely looking forward to the views. I didn't purchase any eye pieces yet but after I get use to the ones that come with the scope I'm sure I will be online looking for my next purchase.

Clear skies.

Blackcat