I'm pretty new to Astronomy and I have a 700mm Newtonian Reflector telescope with 76mm apature. I've tried looking at variouos things but whenever I seem to go out star gazing it's usually cloudy! I use a 2x barlow with 6-8mm eyepiece and 1.5x errecting eyepiece. How good an image should I be aiming to see i.e. if I'm looking at Saturn should I be able to see the rings?
If, for example, with this equipment I shouldn't see Saturn's rings but I wanted to what would I need? Presumably a bigger Barlow would work...But if I were to put a 2x barlow into another 2x barlow would that then act as a 4x barlow?
Also the DigiEyepiece. With my telescope would it be any good for photographing planets?
Thanks very much
Joe
P.S. I do hope I've put this message in the right place!
Yes you should be able to see saturns rings with your setup. However you could be pushing the magnification just a bit by using a 6mm eyepiece with a barlow. The top magnification you would expect and still see fine detail is around 150X magnification. Using a 2X barlow and a 6mm eye piece will give you closer to 233X magnification. While you will be able to see something if you have the type of telescope I'm thinking of you will be hard pressed to track anything at that mag. Try just the 8 mm eyepiece on its own. The image will be small but at least it will be fairly sharp.
What other eyepieces do you have. Any chance of posting a pic of your scope so we can see what sort of mount it is on?
Welcome to IIS Joe, at 700mm focal length with 8mm EP you should easily be able to see saturns rings and give a good view of Jupiter as well. That equates to around 90x mag. (Saturns rings are visible with just 20x mag). Start with just the 8mm ep and see how you go. Unless the seeing conditions are exceptional any more magnification is probably going to make the image worse. Increased magnification doesn't necessarily equate to a better view due to atmospheric effects and diminished light intensity at higher mags. An 8mm EP barlowed 2x (around 180x) is about as much magnification as you could reasonably expect from your newt. Newts also require a period of time for cooldown and collimation needs to be spot accurate for sharp images.
My little bit is that you should easily see Saturn's rings with the 8mm eyepiece. 90x is more than enough to see the rings. You should be able to see the cloud bands on Jupiter as well Don't forget the moon.
A couple of bits that may help:
Your scope is basically a 3" and at the rule of thumb of 50x per inch that means that 150x is your maximum magnification on an exceptional night. Most often the 8mm lense will max you out as this is controlled by the seeing not the scope.
More magnification does not mean better views, that is a marketing gimic to sell cheap telescopes. Magnification is mostly controlled by the seeing, if the stars are twinkling then the seeing is bad and you will not be able to use any great magnification.
Only use good barlows otherwise they just magnify the problems and do not help at all. A bad one will actually degrade your image.
A couple of questions, what type and brand of scope do you have? Does it take 1.25" eyepieces? What ype of mount does it have?
If you can answer these questions or post a picture then we can be of much greater help.
Ok, you should be able to have fun with that. Couple of things yo can do to improve it's performance.
1. Remove that useless slowmotion slider/screwy thing at the side and any other control like that. Get used to guiding it by hand. It will be easier in the long run.
2. With the slidy thing removed see you easy it is to move by hand and if you can tension the nuts/knobs enough so that it stay in place yet is easy to slew without the whole thing( tripod ) moving. If you are having difficulty getting the tension right, take the knobs/nuts off and pack a couple of washers cut from a plastic milk bottle under the knobs and then try getting the tension right.
3. If you have anything left of the milk fill about 1/3 - 2/3 of it with sand (experiment for the right amount) and hang it from your eyepiece tray (it will distort the tray but your tripod will be more stable) It goes without saying to tighten up any loose nuts, bolts and screws.
4. Dont extend your tripod to its full height. Always leave a couple of inches left in the adjustment department.
Try those and see how you go. Welcome to the ATM club (Amateur Telescope Makers/Moders)
Joe to IIS, one thing not mentioned before, for astronomical use don't use the erecting eyepiece, it's unneccessary and does reduce the brightness of your object.
In answer to Rob's quesiton behind the focuser the label just has the spec of the scope - and the little silver sticker says "never look at the sun"!
Well I'd love to say that I've tried all of your advice and it worked but I live in England and hence it's been cloudy ever since I started the discussion! But when the clouds part I'll give it all a go. Fingers crossed...
I have the same scope and am also new to astronomy. I also had trouble seeing Saturn's rings when I first got the scope but can now set it up and view the rings quite fast now. What tricked me was the two lense caps. I was only removing the 50mm cap instead of the larger 110mm cap. I assume the smaller cap is for looking at bright objects such as the moon. When I figured it out I was embarrassed and delighted at the same time as I was then able to see Saturn's rings.
I find the 25mm ep with the 3x barlow works best for viewing Saturn. I was also able to see Jupiters stripes and moons on the weekend from Margret River, Western Australia, dispite the full moon. I haven't seen Titan yet but now I have a new challenge....whats next???
I'll also have to try removing the side support thingy.
hi joe
I hae one of those that i am trying to sell for a mate. same optical tube but on a eq1 mount. you should be able to see a fair amount fo stuff with it like the planets , moon, and some bright DSOs.
my mates one had problems focusing so ghe gave up on it. I found that the main mirror was being pinched cause it was being held in too tight and that it wasnt colimated. if you cant focus properly you prolly have the same problems....
Wow! I was out last night with my scope and was looking at Jupiter. I removed the slidy thing that Paul suggested, didn't use an errecting eyepiece: just a 2x Barlow and a 12mm eyepiece.
The planet was very clearly visible as were the four large moons. I couldn't make out the stripes but put that down to the seeing (I hope my terminology is correct!) not being too good as the edge of the planet was quivering slightly.
Thanks for all your help...can't wait for the next clear night now!
yeah I went out last night hoping to get some observing in but the seeing was about as bad as I have ever seen, starts even right near the zenith were twinkling considerably. Transparency was rubbish too, there was a haze over the whole sky where I was that progressivley got worse until I gave up around 11:30pm.
Best night recently in Melbourne was Anzac Day night. Best view of Jupiter ever, could see some detail in the cloud belts. By Thursday it was getting worse, hence the cloud today...back to early nights again!
Hi Joe,
The scope you have is great for beginners. It will introduce you to a lot of objects in the night sky (shame you aren't in the Southern Hemisphere!). Still you have a lot to look forward to with Orion, M42, is still above the horizon for you in the early evening. Ursa Major has M81, which unfortunately will be just a blob in your scope, but it's still a galaxy far far away! If you do a search on "objects for small telescopes" a whole lot of sites are available for you to browse for more fodder for your scope. Keep lookin' up!
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Don't forget the moon.
& Welcome to IIS. 
L.
