May i ask for some help please

[shazbah]

Hello all. After many months of reading posts and having a small budget , i am now in possession of my first scope which is a celestron C90 Mak.Aperture 90mm focal length 1250m F/13.9. Eyepiece is a 32mm and i have a 2x barlow. Now i really don't know what i was expecting from this scope but so far i feel pretty let down. I don't seem to able to see much more that what i can see with my naked eye.Don't get me wrong i'm not expecting to see saturns rings as i know it's only a beginners scope but i do expect to see something of the planets. Are there any other size eyepieces that someone could recommend for this scope? What do i need to purchase to enable me to see the planets a little better. Sorry for all the questions as i am a total newby and i do not understand some of the Astro lingo like (eye relief and how the magnification works). Thanks for any advice

Sharon

[Carbon Brush]

Hi Sharon.

Early evening you should have no problem seeing Venus as a half disc, like the moon. Jupiter should show (usually) 4 moons around. Sometimes one or more can be hiding behind the planet. You should also be able to make out a cloud band or two on Jupiter. Mars should show as a disc rather than a point. And yes you should see Saturn's rings - much later on when it gets higher in the sky. All of this given a fair sky, which we have had recently.

Can you describe a bit more about what you are seeing? There could be several things going wrong here.

Don't worry about your questions, we are all here to help.

David.

[nightfisher]

Hi sharon, sounds like you might be doing something wrong, it might be the barlow that is not helping, even though your mak is 90mm it should show some planet detail, if you have been looking at mars, it can be tricky to get detail, maybe start with the moon, and see how you get on with that, i have heard good things about the 90mm maks, feel free to ask for more help, depending on where you are you might be able to visit a local astro club and try some other eyepiece`s in you scope, dont be put of

[Atlas]

Could be the eye piece, it's a widefield 32MM. Find your self a good 10MM and you should be fine. Also if everything seems blurry, you may need to colimate your scope.

[shazbah]

Thanks for the info guys. Tonight i was trying to look at Venus and Jupiter but all i can see is a bright star. If i try to zoom in closer i goes all blurry and i get the round black circle showing that's at the end of my scope. I seem to get better results with my camera and 300mm lens with teleconverter.

Atlas i think you may be right about the eyepiece. I don't really understand how they work as i thought 10mm would give me less that 32mm not more magnification. (gosh this astronomy makes my head spin).

Is there a particular 10mm piece i should get??

Thanks

Sharon

[umadog]

It's a Mak, it won't need collimating. What it may need is cooling down.

[shazbah]

(cooling down) does that mean leaving it for 20 minutes outside before using??? If so, that's what I've been doing

Sharon

[Atlas]

It's a Mak, it won't need collimating. What it may need is cooling down.

Ah yes, I didn't notice that part.

[king-jaffethehutt]

should have reasonable views with your 10mm works out 125x, and only 39x for your 32mm though 250x and 78x respectively with your barlow.

Maximum mag should be kept to the 2x the aperture rule giving you a usable 180x.

I suffer dreadful condensation with my mak :-(

[king-jaffethehutt]

p.s the black patch is the shadow of the mirror in the center of the primary mirror.

[shazbah]

Thanks all. I will order a 10mm eyepiece

Sharon

[Tinker1947]

You should use a wide EP (High MM) to find you target, center it then change to higher power (Low MM)to bring it in a bit closer, using a Barlow while this increases the magnification it also add glass to the view and unless its a good quality Barlow it may make thing worst, so put a wide EP in the focus tube and start with right out or right in and move it slowly until it reaches the other end of its travel, some where in between you should get what every your looking sharp and view able, if not you may need a extension tube 2" in length should do the job.

[nightfisher]

If you plan on buying a 10mm eyepiece, go for a GSO/revelation plossl, they work very well in mak scopes, though they dont do a 10mm its a 9 or 12mm with these.

have you downloaded stallarium software, its free and really good for finding your way in the night sky, I have a 15mm non branded plossl eyepiece you can have for nothing, as i dont use it, let me know

[DoctorD]

Hi Sharon

You cannot zoom with an astronomical telescope - the knob

Is for focussing. You need to adjust this to get the sharpest view - this will need adjusting when you change we piece.

Planets are always going to be small but you should be able to see the rings on Saturn and two bands on Jupiter along with its four moons.

Try pointing your scope at the moon - the level of detail should be astounding compared to the naked eye view.

Hope this helps

Paul

[JamesF]

It may also be worth practising by viewing distant buildings/trees/telegraph poles/whatever during the day, just to get the hang of it.

As Paul says, you can't "zoom" with a telescope. Turning the knob alters the focus. What it's actually doing is moving the mirror backwards and forwards inside the telescope body. At the correct position that will mean that the point of focus is right where you need it to be for the eyepiece you're using. Unfortunately if it's too far out sometimes you just can't see anything, so until you get used to things you may have to go backwards and forwards quite a lot to find the correct position. If you get to the point where you see a white ring then you're close. You need to turn the knob to make the ring shrink in size and you'll get to the point where it forms an image. If the ring becomes less distinct then you're probably going the wrong way.

The magnificiation of a telescope is fixed by the eyepiece and focal length of the telescope. As you talk about cameras I'll assume you understand focal length. For the C90 it's about 1250mm. If you divide that figure by the focal length of the eyepiece that gives you the magnification. So, with the 32mm eyepiece you'll get 1250/32 = 39x magnification. A barlow increases the focal length of the telescope, so your 2x barlow makes the focal length 2500mm, effectively doubling the magnfiication to 78x.

Obviously by the same rules, a new 10mm eyepiece would give you 125x magnification. There are two limits to magnification however. The first is that the maximum magnification of a telescope is considered to be about twice the aperture in mm, so 180x in your case, and that in the UK the distortion effects of the atmosphere means that anything more than 250x is rarely usable.

The other side of the coin is that increased magnification will give you a smaller field of view. Whilst that's great for planets, it's not so good for deep sky objects such as nebulae, star clusters and galaxies. You might want to stick with a lower magnification and wider field of view for those.

James

[JamesF]

I'll add:

As others have said, you should be able to see some banding on Jupiter and four of it's moons, although it's very low in the sky at the moment and that will affect the quality of the image.

Venus is very bright and you won't be able to make out any detail, but you may be able to see that it has phases, just like the moon.

Mars is very well placed for viewing at the moment, but it is very bright and you may need to sit and look at it for some time to allow your eyes to adjust to be able to pick out detail.

Saturn is getting better for viewing, and whilst it will look small you should be able to see the rings. You may even be able to pick out one or two moons.

Other things you might look at right now are the Pleiades (getting low on the western horizon, sadly), the Orion nebula and the Beehive cluster. Those should all be relatively straightforward to find.

James

[boabsta]

Can I just add, take your time. Try not to get frustrated and you will have your wow moment when it all comes together.

As a few others have said, try the moon 1st. You've never seen the moon until you see it through a scope.

[JamesF]

You've never seen the moon until you see it through a scope.

That's very true. Especially when it's only partially lit. The full moon appears quite flat and featureless compared with the times when it's partially lit when it's possible to make out many more craters and see the shape of the landscape because of the shadows.

You'd almost believe it was real

James

[knobby]

Ill second that ... look at the moon when its half lit, it makes the details really pop

and don't give up, if youre a photographer well focusing a telescope is a bit like manually focusing a decent macro lens ... its difficult but you'll know when you get it right

Good luck

[shazbah]

Hi all and thanks for all the info

I first started off with my camera and a 300mm lens and was amazed at the quality pics i got from the moon. From then on every time the moon came out so did my camera equipment. Then i started looking around the sky and have always had an interest but no knowledge. I bought the mak and it is great for the moon but my problem lies when now looking at other objects and thats what led me here so i can gain some knowledge from you guys.

James: I have practiced with the scope during the day as it is also a spotting scope and this has helped me familiarise myself with the focusing knob.

Knobbly: I do quite a bit of macro photography and yes you are right in saying that it takes plenty of patience to get the focus correct.

I can't wait to get my wow moment but at least I've learnt that i wont get it with a 32mm ep. I was quite impressed with my self last night for finding Mars let alone viewing it (had some help from stellarium)

Nightfisher: that is a very generous offer that i will take you up on and i will send you a pm

So now i know i need a smaller EP and lots of practice and patience

Now for the last question..............

Can anyone recommend a good sturdy tripod for the scope?

i have been looking at the Horizon 8115and the Skywatcher synscan AZ goto mount and tripod and the Manfrotto 055xprob tripod with 128RC head.

Any opinions would be welcome as i really need to get one a.s.a.p

Many thanks to you all

Sharon

[JamesF]

Mars does look tiny in a 32mm eyepiece, it has to be said. A shorter focal length eyepiece should make a significant difference. Mars is a small planet though, and takes time to get used to viewing, so you shouldn't get too dispirited if you struggle with it. Despite it's far greater distance from us (about 1,500,000,000 km, iirc), Saturn is larger and probably easier to discern detail on, such as the shadows cast on/by the rings, the Cassini division and its moons.

You do have a perfectly good scope with which it's possible to see a great many things in the night sky, but you also have to remember that it's relatively small compared to those many other people on these forums are using and you're not going to be able to reproduce the views they get. They might see dust lanes and make out individual stars where you only see a slight fuzzy patch. Everyone has to start somewhere though

James

[sologuitarist61]

The Skywatcher Synscan AZ is OK if all you want to do is use it visually, but it seems to me that you are a keen photographer as well (as am I) so I guess that eventually you will want to take pictures, then the Synscan AZ Goto will let you down as it always maintains the same orientation whilst the sky moves and objects in it will change over time as the heavens revolve and that makes for difficult stacking of images, and smearing of long exposures.

Have you looked at the Skywatcher EQ3 Pro GOTO mount? This is a German equitorial mount and so avoids the orientation of the object moving over time. Should be big enough for your Mak.

[shazbah]

Thanks

Yes i have looked at the EQ3 pro goto mount but it looks way over the top for my little scope, it is only 41cm with the diagonal and ep and weighs only 2.3kg

Sharon

[sologuitarist61]

Thanks

Yes i have looked at the EQ3 pro goto mount but it looks way over the top for my little scope, it is only 41cm with the diagonal and ep and weighs only 2.3kg

Sharon

Don't think that way - as you get into astronomy your expectations will change and before you know what you will want a bigger scope and then you will need a new mount. Best to get the biggest you can afford now and save losing money buying and selling.

[knobby]

But when you strap your DSLR on it ...