Celestron astromaster

[Biggazza88]

hi all!

just after some advice on my new astromaster 130 eq, trying to find out if i brought a 'toy' or a ok starter scope,

i added a celestron x-cel lx 5mm lens to the existing equipment supplied (10mm and 25mm erecting EP,)

any thoughts hints and tips appreciated!!

cheers, gary.

[rory]

nope , not a toy, perfectly fine telescope gary. you might want to get yourself a collimation tool . also you might find the red dot finder a pile of rubish,but try it out first and see how you get along.

congrats on your scope. so what are you planning on viewing mainly ? moon ,planets or dso's (deep sky objects) ?

[Biggazza88]

ahh thats good news, i didnt get a dud! iv had some good views of jupiter and some of her moons but thats about as far as iv got so far! theres no moon at the moment so im looking forward to having a good look at that! iv heard that most dso's are a bit dissapointing because they just look like a small fuzzy smudge but i will still be trying to find some the red dot finder is a bit pants but im waiting for the moon so i can have a go at property alligning it at a decent distance instead of just looking down the street at a chimney pot or telegraph pole.

nice x-cell collection you have there too! big monies in you EP case what do u think of them? any good?

[JamesF]

Not all DSOs are grey fuzzy smudges, but some certainly are. Globular and open clusters are usually easily visible, whereas galaxies and nebulae can be more tricky.

James

[rory]

the x-cels are pretty good for the price (can be picked up under £60 in some places) i like them alot.dont know about big money,you wanna see some peeps cases on the forums, trust me my set up is cheap by comparison. the finder on the astromaster gazza is well known for being a dud. but everything else is pretty much good to go. you'll find alot of forum members will recomend the rigel finder or telrad finder to replace the dot finder you have,and for good reason,they are simple and they work well.

i had a astromaster and i got by with no finder for nearly a year,i just used a low power eyepiece as a finder (32mm plossl) but once i got a telrad .it made a huge difference in getting to the right area.

[Biggazza88]

while looking at jupiter the other night i think i found m42(?) paladies(?) cluster, looked awesum but i didnt know what it was till i looked it up! gorgeous looking group of stars whatever it was!!

[Biggazza88]

you'll find alot of forum members will recomend the rigel finder or telrad finder to replace the dot finder you have,and for good reason,they are simple and they work well.

any ideas on where i can pick these up at a decent price? no point in upgrading the scope too much as it wasnt too expencive anyway!

[rory]

http://www.firstligh...-astronomy.html

http://www.firstlightoptics.com/finders/rigel-quikfinder-compact-reflex-sight.html

here. they are the forum sponsors,and have a reputation as good as anywhere.

[Biggazza88]

awesum, the telrad looks great! might have to invest thanks for ur help mate.

[rory]

while looking at jupiter the other night i think i found m42(?) paladies(?) cluster, looked awesum but i didnt know what it was till i looked it up! gorgeous looking group of stars whatever it was!!

one more tip for you. if not done already, download "stellarium" its a free software planetarium,its a fantastic bit of kit that wont cost a penny and you can do alot of searching on it and find out whats up there and when.

http://stellarium.org/

here you go.

welcome to the forums gazza, and clear skies to you.

[Qualia]

iv had some good views of jupiter and some of her moons....iv heard that most dso's are a bit dissapointing because they just look like a small fuzzy smudge

I wrote something very similar last night to another member who has the same OTA as you, Biggazza, so I do apologise if I'm repeating myself. With regards to the DSO's etc, this is a rather subtle hobby and I guess it's art is tweaking out extremely subtle detail from objects very, very far away. But this is exactly the fascinating aspect of stargazing's possibility. It's just mind blowing that with a little inched bit of glass or mirror we can actually contemplate such objects and I think this aestheic appreciation is augmented if we pursue our hobby by also informing ourselves of what we have seen and adding this to what we already know. Sure, they may be just faint fuzzies to many who gaze for a second and turn away but for the careful stargazer they are so much more, not only in our understanding of them but also in what they reveal.

You'll need to collimate your scope quite regularly. So if I were you, I'd use a little money for a collimation tool like a Cheshire and collimation cap.I'd forget filters for now and after a few sessions with your well collimated telescope, you might want to consider up-grading the eyepieces along with your 5mm X-Cel LX. BSTs also come highly recommended and your reflector is going to be a wonderful instrument for scanning Milky Way star fields, open star clusters, globulars and other large astronomical objects, so in view of this, and in light of the rather poor finderscope, you might want to think about getting a decent widefield EP of say around 25mm to 32mm and a Telrad. That way, not only do you have a lovely EP to scan the cosmos but it doubles with the Telrad as an excellent tool for learning the art of star hopping. If you then purchased a decent x2 barlow, you've effectively doubled your EP case. Jupiter doesn't really take magnification well, so you don't want to push beyond x160.

Check out sketches to get an idea of what you will be viewing, download stellarium, get a decent Star Atlas, dress warmly and take your time. Welcome to SGL, Biggazza and congratulations on your new telescope

[Biggazza88]

ill look into it now! :icon_mrgreen:

[Radders]

+1 for the Telrad. Best accessory I've purchased.

[nicks90]

You'll need to collimate your scope quite regularly. So if I were you, I'd use a little money for a collimation tool like a Cheshire and collimation cap.

i've also got the same scope as you biggazza and I had problems collimating mine initially. Dont go and spend money on a laser collimator or anything just yet. Problem is the primary doesnt have a spot or sticker in the middle of it and you cant easily get the primary out to put one on - as its all held in place with little screws with nuts on the end. I havent yet figured out how to get my hand down there to hold the nuts to dismantle it.

However, I did make a collimation cap out of a 35mm film canistor by heating up a bbq skewer and poking it through the middle and using that to align the secondary mirror. Also, the view through the colly cap - or without it - you cant see all 3 primary mirror clips (something common in 'fast' scopes supposedly) and therefore its hard to even gauge if the secondary is somewhere near in the middle (using best guess, as no centre point on primary!!!).

So what I did was sort out the secondary with the colly cap - which was surprisingly easy to do, just twiddle the 3 allen headed screws until the point of light from the colly cap hole is in the middle - and then go outside and focused on jupiter and then unfocus it so i could see the 4 spider arms and the black centre (secondary) inside the big fuzzy white blob. As it happened the black centre was slightly to one side. I then adjusted the primary until it was in the center and did it that way - is that called 'star collimation'?

Either way, seemed to have worked as it seems a bit better on high mags of jupiter after that.

[Biggazza88]

Ah cool, I havnt even had a look at fiddling with the mirrors yet but it's somthing I will have to try at some point soon I'm sure! Sounds like you got it down to a fine routine with the use of Jupiter tho, congrats and thanks for the tips, much appreciated!!

[AstroTux]

Just to let you kow that the primary mirror can be removed and centre-spotted quite easily if you are very careful. At the bottom end of the 'scope you will see a number of screws - three large silver knurled headed screws that adjust the primary mirror tilt, three silver cross-headed screws that lock the mirror position and three black cross-headed screws that hold the primary cell in place in the bottom of the tube.

If you place the tube on a soft surface and carefully undo the black screws you can slide the primary mirror cell gently out of the tube ( be very careful not to drop or knock it or you may damage your mirror ).

Once the primary is out you can centre-spot it. Take a piece of kitchen greaseproof paper and place it on top of the mirror so that it follows the curve, then gently draw around the mirror's edge with a pencil. You need to try and be as accurate as you can whilst you do this. Also mark on the paper which edge goes where so that when you remove it you can put it back exactly.

Now remove the paper and fold it in half so that the line you have drawn is matched on both sides of the fold. This gives you a fold straight through the middle of the mirror. Fold the paper again ensuring that the lines match again and you now have two folds. Where they cross is at the centre of the mirror. Make a very small hole at this point and then place the paper back over the mirror ensuring that you get it is accurate as possible.

You can then use a red CD marker, or other soft pen to mark the centre-spot of the mirror through the hole. You may also ( or instead ) want to place a sticky paper reinforcing ring carefully around this centre-spot, although this needs to be done precisely. Once you have done this you may want to gently clean any dust away using a lens blower brush, nothing more.

I have a red CD marker pen spot on mine as I use a laser collimator and the dot lights up when the laser hits it, but you may want to use a reinforcing ring if you are using a cheshire collimator.

You can then re-insert the mirror cell back into your 'scope ensuring it goes back the same way that it came out, and then collimate your 'scope. Please don't do this if you don't have the means of collimating as this process will destroy any collimation you already have.

Another issue I had with this 'scope was that the secondary mirror of mine was way out of position. It was too far from the primary so that when you sighted it through the focuser it was towards the left. When I placed it correctly in the middle of the field of view my collimation became 'spot-on', but this also affected the focus of my 40mm eyepiece and I had to purchase an extender tube to ensure that I could get focus with it. All my other eyepieces however can be focussed without it.

Hope this helps :grin: ........

[Biggazza88]

Great bit of advice there mate, thank you very much!

[nicks90]

^{If you place the tube on a soft surface and carefully undo the black screws you can slide the primary mirror cell gently out of the tube ( be very careful not to drop or knock it or you may damage your mirror ).}

^{how the hell did you do that? When i turn the screwa, it loosens off a little, but then the small nuts on the inside of the ota just rotate. The only way i can see of getting those screws out is to somehow hold the nuts on the inside of hte ota to allow the screws to fully unscrew. That will then leave the great job of somehow holding the nuts in position whilst you screw the screw back in!}

[AstroTux]

^{If you place the tube on a soft surface and carefully undo the black screws you can slide the primary mirror cell gently out of the tube ( be very careful not to drop or knock it or you may damage your mirror ).}

^{how the hell did you do that? When i turn the screwa, it loosens off a little, but then the small nuts on the inside of the ota just rotate. The only way i can see of getting those screws out is to somehow hold the nuts on the inside of hte ota to allow the screws to fully unscrew. That will then leave the great job of somehow holding the nuts in position whilst you screw the screw back in!}

That's a wierd one. The nuts in mine are held captive by the plastic lugs that the screws line up with inside the tube. All the other AstroMaster 130s I've seen are the same.

What happens if you try to hold the nut in place by using outward pressure on the screw ( ie. pulling the top of the screw away from the base plate as you loosen it )? If you could get the screws out this way you may then be able to investigate why they are rotating when they should be held in place.

Hope this helps.......