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Old 19-04-2012, 02:22 PM
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Shopi (Shannon)
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Advice (Bushnell and 12" SW Goto Dob)

Hi all,

Just joined the forums, I've always been facinated by space, stars, and our other orbiting bodies. When I was younger, I had a basic telescope only really any good for looking at the moon, For some unknown reason something clicked in the last few weeks and all I want to do is stargaze.

Our local leading edge had a sale on they're scopes so I picked up a Bushnell Voyager 900*114m Reflector (789946) All excited i set it up etc and heading out that night to a nice little dark lookout over the mundi mundi plains.

Once we set up and ready, I was sorely disappointed in the scope, (manual said about looking at the rings of Saturn and the spot on Jupiter etc). I've no idea if it was noobishness or the expectation i had in the scope, but all I could see where stars (bright lights) through the eye piece no different from as if I was using my naked eye. (I tried all the eye pieces in combinations with the barlow and with out 4mm, 8mm and 12.5mm) As, I said, I'm not sure if I did something wrong or it was just a waste of $210 (havn't had the chance to glimps the moon as yet.

So i guess any advice as to the Bushnell would be welcomed! but also an opinion as to a 12" skywatcher Go2 Dobs ( http://www.skywatcher.com/swtinc/pro...1=1&class2=106 ) review - http://www.skywatchertelescope.net/s...review-web.pdf

Ideally, I'd like to be able to do a bit of everything, but as from what I've read no 1 scope does it all, Would the Dob allow me to view planets etc as well as DSO's? Has anyone used this scope / recommend? I'd also like to look at getting into the astrophotography once time and $$$ permitted (I've already got a Canon 350D (Not sure if this would be attiquate etc as well)

last question how safe is it to travel with such a large scope (back of a ute etc? )

Thanks in advance

Shannon
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Old 19-04-2012, 05:10 PM
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Allan_L (Allan)
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Hi Shannon.
The Bushnell, is that a goto scope?

I had a Bushnell 114cm goto a long time ago, and i found it OK to use on planets. Rings of Saturn, yes. But pretty small image, but still discernible.

But not too good for faint DSO's, even though with the goto you could at least have a good chance of finding them, even if you couldn't "see" them.

But the SW 12 go, that is a real scope.
Yes it will be much better to see DSO's and will have a more accurate GoTo computer navigation system.

I am currently using a SW10inch (non goto) and I am very happy with it.

Now, back to your "seeing" problems.
Your strong eyepieces (lower number mm) give higher magnification, and the Barlow just doubles magnification. But there is a limit to how much magnification you can "use" and still see a decent image. The size of your scope (diameter) determines how much light you are getting, and this determines the practical maximum magnification you could expect (irrespective of barlows etc.).
Additionally atmospheric conditions can also reduce your ability to use too high a magnification. So the less atmosphere you have to look through the better. (So basically, the higher in the sky the better).
One more thing is your own eyes need to be dark adapted, which can take 30 minutes away from bright lights. We use RED lights as these do not disrupt your night vision.

Welcome to IIS
Hope you enjoy the skies.
Ask many questions.
Try to get along to an observing night to speak to others and learn from their experience (and to see through their scopes and eyepieces).
Keep looking up !
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Old 19-04-2012, 05:49 PM
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andyc (Andy)
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Hi Shannon,
I just looked up your scope on Amazon, and I think I see your problem. It ships with three rather high magnification eyepieces for the size of the telescope, and the mounting was reviewed as being quite unsteady. With a 900mm focal length, the eyepieces give magnifications of 72x, 100x and 225x. The 225x is probably unusable on the supplied mount, and 72x is already quite high for the size of telescope. If the eyepieces are of poor quality (the ones that shipped with my Celestron 130mm reflector were rubbish), then your view may be less than impressive. But don't despair! For now, I'd stick with using the 12.5mm (72x) to try and find objects, and see if you can get views of any of the brightest deep sky objects, say in the Milky Way near the Southern Cross. Your challenge will be to learn some constellations and see if you can find your way to some of the objects (if you don't already know). Mars and Saturn are both in the evening sky at the moment, though you won't see very much on Mars with your scope I suspect (Mars is tiny), but the rings of Saturn are definitely there for the taking, and truly magical the first time you see them in a telescope! A pair of binoculars, if you have them, can help you identify what your telescope is pointing at by giving you a low magnification view of that part of the sky.

The 12" scope you've identified is a good big one, and could lead to a lifetime of observing all sorts of deep sky objects, quite apart from the Moon and planets. Aperture is ultimately what matters most for nearly all astronomy, and 12" is a good bit of aperture! !t will take a bit of learning your way about the sky and learning to find interesting stars and deep sky objects, and you should be prepared to be frustrated at first. This takes time but is incredibly rewarding in the end.

If you don't want to spend big bucks right away, the best quick improvement to your little telescope would be a low-power wide field eyepiece. With a focal ratio of 7.8, your telescope would support a 32mm or 40mm low power eyepiece, for example this simple one from Bintel for $39:
http://www.bintel.com.au/Eyepieces-a...oductview.aspx
That will give you a much wider field of view and a much higher chance of locating objects, and of relating what you see in the telescope to what you can see with your eyes and binoculars. It would turn your little scope into a little rich field telescope! Objects like Eta Carinae nebula, the LMC, the Jewel Box and Omega Centauri could be fun to look at with this! Adding a small finder (e.g. a 6x30 sold at Bintel for about $50) might also help - I did this with my 130mm Celestron and it made it an awful lot easier to use as I could locate objects much, much more easily. I had to drill two holes into the tube to mount the finder but it was well worth it!

Other advice is to find a local astronomy club, go to a star party, and look through other people's scopes, small or large, and chat to them. You'll get more of a feel for different telescopes and perhaps a better idea of what's good value for you as well.

Oh, and ! Clear skies!
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Old 19-04-2012, 07:02 PM
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Shopi (Shannon)
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Cheers

Thanks Allan & Andy,


The bushnells a normal scope no go to, it does come with a sky tour thing, punch in your details and takes u on a tour, gimmicky but still cool =]

The stand is hideous, wobbly as hell, and the tightening screws are just frustrating, finally line it up with the red dot, tighten and then watch the tube move a few mills lol, frustration is actually a rather moderate feeling.

I'll have a look at the new eye pieces that you've suggested, and purchase them, hopefully will tie me over till I've got the dollars together for the 12" I've a okay knowledge of the night sky (on a basic level, Venus, Jupiter, Saturn, etc and a few costollations, but the best bit, I've a pretty awesome app on the iPad (star walk) that fills all the gaps in.

I've tried to look at Saturn with the eye pieces that I have and no rings on Saturn, just looked like a star in the scope or a fuzzy blob when zoomed in, so with the new eye pieces, I'd have a better chance of seeing the rings? (rather excited truthfully about seeing them with my own eyes)

Thanks again gents =]
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Old 19-04-2012, 07:24 PM
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andyc (Andy)
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If you go down the line of adding a new eyepiece, I'd probably just go for one eyepiece for now (32mm would give you ~30x, a nice low magnification for wide field viewing and less 'shake' too), then save the dollars up for a bigger scope. You should see Saturn's rings clearly in all your eyepieces, so I'd maybe make sure you're pointed at the right object (not meaning to be condescending or anything, but I know from experience it's easy to miss with a red dot finder!). Right now, there's a star that's similar to Saturn in brightness not far away in the sky - the star Spica in Virgo, and above Saturn in the early evening. It's colour is white or bluish white, while Saturn is about the yellowest object in the sky. So if the blob/star you think is Saturn is not yellow, you may not be pointing at it! Saturn should not appear 'stellar' (ie a single point) in any of your eyepieces. Even in the low power eyepiece I suggested it would appear as a tiny oval with the rings just discernible, and in your 12.5mm eyepiece they should be quite clear. If the blob you're looking at is yellow, then I wonder if something's up with the optics of your scope (poorly collimated, something else)?
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Old 19-04-2012, 08:40 PM
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Shopi (Shannon)
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Thanks Andy, whipped out the scope to make sure I was pointing at the right spot, worked out what I was doing wrong (was on Saturn =P) the issue was my expectation I guess I was expecting it to take up most of the scope, and when, I was focusing I was going to far past or to far back and missing the 'focus' point. I'm pleased to announce u helped pop my Saturn cherry =] all 3 lenses, saw Saturn =] the main issue I'm having is the stand and lock bolts, is it possible with this scope to upgrade the stand and fix the scope tilt rotate bolts? I've searched google endlessly, but all I seem to find are sales pages and the occasional review (I'm guessing it's not an overly popular scope or newish low end scope and not in wide circulation). I realize u don't know the scope 1st hand but, I appreciate the time you've taken out to help


Shannon
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Old 20-04-2012, 02:18 AM
ColHut (Colin)
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Is yours like this? http://www.telescopes.com/telescopes...ithskytour.cfm or http://www.bushnellaustralia.com.au/...er_789945.html

How do you point it? Are they twist dials connected to alt/Az gears (see link above). If so it looks as if they have taken the 'goto' out of their "Northstar" goto/'kinematic' with RVO series and replaced it with dials for pointing. It looks essentially like that anyway. There is a review of same in the review section.

Keeping the tripod low will help improve stability. A couple of plossels (if you got lesser eyepieces marked "R", "H", or a little better "MA") will be useful. Do you have some pics of your eyepieces?

I agree a 32mm plossel will give maximum low power widest possible view for you scope. You might consider one about 10mm and a Barlows x2. Check out Bintel or Andrews. The GSO models are perfectly fine and cheap.

You might find it blows about a lot in the breeze.

A 6 or 8" dob might be better and sell the one you have if it become too frustrating.

Good luck and welcome aboard.
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Old 20-04-2012, 06:14 AM
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ZeroID (Brent)
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Hi Shannon and
My first 'decent' scope was a 114mm newt similar to yours. My mount was a bit more steady though but I improved it no end by hanging a reasonable weight down off it between the legs. About 5 kg of solid steel helped by stabilising the whole thing on a bit of chain attached up by the head.
And even in suburban skies in Auckland I can make out dustclouds in the Great Neb in Orion, Eta Carina and a lot more.
It's more a matter of getting used to what you are looking for and some dark adaptation. I still use my 114 because it is quick and easy to setup and am adapting it for eventual use as an Astrograph.
I tend to use either a GSO 20mm or 15mm Superview for most viewing. The high power EPs tend to demand better seeing conditions so get used rarely. Lowest I'd use is a 9 mm TMB planetary and that would be pushing it.
I hope you've loaded Stellarium onto your PC. It's a huge help in learning the skies and what to expect.
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Old 20-04-2012, 10:06 AM
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andyc (Andy)
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Quote:
Originally Posted by Shopi View Post
I'm pleased to announce u helped pop my Saturn cherry =] all 3 lenses, saw Saturn =]

Glad I could be of use , planets are a lot smaller than you expect! You should look at Venus just now if you have a low enough northwestern horizon after sunset - it will show a fat crescent shape in your scope that will get bigger and thinner over the mext month or so as it heads between us and the Sun. Then the next challenge will be to find some bright star clusters and nebulae!

Afraid I don't have much other useful advice on the scope itself (ZeroID and ColHut have provided some useful suggestions though). It's probably not worth spending a very large amount of money on this telescope, though if you do buy an eyepiece or fider for it, they can be transferred to a new telescope so you're not wasting $$$. Your best bet may be to save for a better scope - as starter telescopes the 6" or 8" dobs give great value for money, and particularly the 8" has good light-grabbing power. But that said, I still use my 130mm reflector when I just need to nip out and look at something, there's plenty potential in these little telescopes.
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Old 20-04-2012, 02:54 PM
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Vegeta (Ibrahim)
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The Dob would be an exellent option. But as Andy and Brent said, the smaller scope still has a lot of potential. my little 60mm refractor is still used more often than my 12" dob because it is smaller, lighter,easier to set up, and is not as sensitive to seeing as the dob so i can use it for a quick glimpse of the sky. ( I also don't have to break my back setting it up like the dob)

The 12" dob would have a lot more light gathering and resolving power than that of your current reflector, so DSO's will show details invisible to the smaller scope.
My 12" dob is a solid tube, but i can still safely transport it in the back of a stationwagon or 4WD (but i often lose a back seate), so transportation should't cause much of an issue considering it can collapse, but i can't make any promises because i've never tried it in a ute.

Hope this helps
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Old 23-04-2012, 06:13 AM
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Shopi (Shannon)
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Thanks guys, sorry for the late reply day 4 out of 5 today (work), been buggered all week and hardley even looked out at the computer.

Col that's the scope I've got, just basic as setup no dials hanging off the Alt though for fine adjustments etc Just 1 twist knob and hope it don't change degrees when u let go, there's a small dial for the Az to do the fine work there. Tripod's as low as it can go Will give Zero's idea a crack this week with a 5Kg weigh in the centre, hopfully that will help a ****ton! You are correct though Col, it does get affected by the breeze and 'bounces' around with anything more then a sneeze at it.

Wasnt aware of the Stellarium software, but have since installed and started playing with (Thanks for the Tip)


Thanks for the help in general guys, I appriciate it muchly! I'll keep scowering the forums reading up, but whilst, I'm doing that I'll be saving for the 12" goto DOB (Tim Allen grunt)


Shannon
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Old 26-04-2012, 04:41 PM
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yes goto 12" dobbie all the way
I have had mine for 12 months now and i love it
You wont regret it
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