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Hello everyone! 

I have a Celestron Astromaster 70az. I've been on winter break recently and have got the opportunity to utilize it in the evenings and early mornings. I used it this morning around 4-5 am IST to spot Jupiter, and boy was I overcome by excitement. Since I acquired this scope from my cousins', it's been rather untouched. Perhaps the alignment/collimation is off but I only see a distant white speck. It could be the shortcomings of my telescope but I would rather have you guys correct my understanding on this as I am a novice to astronomy. 

My main inner debate was whether I should look for extra accessories or purchase a more powerful scope good enough for planetary observation. (Sidenote: I have a 20mm and a 10mm scope that came with this box). 

Now, I live in the middle of Mumbai which is a bustling city. I realize light pollution and other pollution also factor in greatly. I would like to hear more experienced people out before making hasty decisions.

Thank you, 

-H

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Hi.

Jupiter should be fine in a 70mm scope.Find it in your 20mm first and make sure it's in focus.Keep looking and after a few seconds you'll make out some detail and moons. Then put your 10mm and refocus. It will obviously be bigger. Jupiter is so bright that light pollution shouldn't be a problem.

I have a 70/700 scope too. I would recommend learning with it before getting a new scope. These scopes are just so light and easy to set up and put away again. I've just upgraded with a couple of cheap plossl eyepieces and I'm really satisfied but my old ones were probably worse than yours. Of course dreaming about a better scope is part of the fun.

Good luck.

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Personally I would enjoy what you have as in the first response ( but it is a small beginner scope ) then wait to move to a bigger one, I would not bother with extras for this scope , better to move up.

a small scope will only ever show small things.

 

Edited by alanjgreen

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A 70mm aperture telescope certainly has its limitations compared to larger scopes in terms of the detail it will reveal and the maximum magnification which will be possible. But it will also allow you to see a lot of objects.

Telescopes in India are expensive - and have to be bought from a small number of dealers or specially imported. If you are able to afford a better telescope and want to develop in the hobby, I would certainly recommend buying one - either now or at some point in the future. However in the meantime there are plenty of targets to observe, so there is no need to hurry.

Your telescope comes with two eyepieces which give different magnifications - the 20mm will give x45 and the 10mm will give x90mm. The maximum theoretical magnification of your telescope is about x140 - although in practice I would keep below this. Using a 7.5mm eyepiece, you would obtain a magnification of x120. You don't need to spend a fortune: basic Plossls by Celestron, Skywatcher or GSO would give acceptable results - however avoid the very cheapest eyepieces as the quality is very poor.

Eyepieces can of course be transferred between telescopes. However their magnifications depend on the focal length of the telescope, so this may change with a new telescope.

Remember, though, that the planets are always small when seen through amateur telescopes. Don't expect to see the detail you've seen in photos taken from professional telescopes and space probes!

Light pollution is sadly a great problem in astronomy. If you ever have the opportunity to take your telescope to a rural area with less light pollution, you will be amazed at what you can see with it! :icon_biggrin:

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46 minutes ago, domstar said:

Hi.

Jupiter should be fine in a 70mm scope.Find it in your 20mm first and make sure it's in focus.Keep looking and after a few seconds you'll make out some detail and moons. Then put your 10mm and refocus. It will obviously be bigger. Jupiter is so bright that light pollution shouldn't be a problem.

I have a 70/700 scope too. I would recommend learning with it before getting a new scope. These scopes are just so light and easy to set up and put away again. I've just upgraded with a couple of cheap plossl eyepieces and I'm really satisfied but my old ones were probably worse than yours. Of course dreaming about a better scope is part of the fun.

Good luck.

 

Definitely, I really love this scope because of its mobility. Any particular eyepieces that you'd recommend getting?

 

47 minutes ago, alanjgreen said:

Personally I would enjoy what you have as in the first response ( but it is a small beginner scope ) then wait to move to a bigger one, I would not bother with extras for this scope , better to move up.

a small scope will only ever show small things.

 

 

I think I'll spend a few more months on this scope and then in June around my birthday wait to pick up a better one. Thanks!

28 minutes ago, Putaendo Patrick said:

A 70mm aperture telescope certainly has its limitations compared to larger scopes in terms of the detail it will reveal and the maximum magnification which will be possible. But it will also allow you to see a lot of objects.

Telescopes in India are expensive - and have to be bought from a small number of dealers or specially imported. If you are able to afford a better telescope and want to develop in the hobby, I would certainly recommend buying one - either now or at some point in the future. However in the meantime there are plenty of targets to observe, so there is no need to hurry.

Your telescope comes with two eyepieces which give different magnifications - the 20mm will give x45 and the 10mm will give x90mm. The maximum theoretical magnification of your telescope is about x140 - although in practice I would keep below this. Using a 7.5mm eyepiece, you would obtain a magnification of x120. You don't need to spend a fortune: basic Plossls by Celestron, Skywatcher or GSO would give acceptable results - however avoid the very cheapest eyepieces as the quality is very poor.

Eyepieces can of course be transferred between telescopes. However their magnifications depend on the focal length of the telescope, so this may change with a new telescope.

Remember, though, that the planets are always small when seen through amateur telescopes. Don't expect to see the detail you've seen in photos taken from professional telescopes and space probes!

Light pollution is sadly a great problem in astronomy. If you ever have the opportunity to take your telescope to a rural area with less light pollution, you will be amazed at what you can see with it! :icon_biggrin:

 

So far, I've only bought one telescope and that too from an online store, they are, unfortunately, expensive. Looking at the variety of telescopes and accessories made me dizzy, and that was just the Celestron website. However, I'll stick in there and do my research before upgrading. Thanks :icon_biggrin: .

 

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Post on this forum when you get down to your final three choices of scope. We can help with pros and cons of each one :)

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Some people are too dismissive of what small telescopes can do. A 70mm refractor of good quality will show interesting views of the Moon, Jupiter, Saturn and the brighter stars and consistently perform closer to its theoretical limits. It will be less affected by bad viewing conditions, and on some nights, or on planets low in the sky, a big telescope will not show much more detail than a good 70mm.

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20 minutes ago, HridaySabz said:

Definitely, I really love this scope because of its mobility. Any particular eyepieces that you'd recommend getting?

Sorry others are more qualified than me. Just check that your eyepieces don't have an H written on them.If they do then anything will be an upgrade. The consensus seems to be that the book turn left at orion is one of the best upgrades possible. I got stuck after looking at the planets and this book shows you how to find some great sights in a small telescope. It can be frustrating after a short while just looking without having an attainable target. At the moment Orion is a real beauty of the night sky.@Cotterless45 posted a great piece called Observing Orion on this site and I've been looking for a few of the things he mentioned.

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I love my borg89 for wide field, but my upcoming 20inch is going to blow it away on my favourite galaxies.

my 11inch SCT gets all the main objects up close and personal, but the frac just shows a small thing in a wide field. It's very sharp image, but a small thing is all it can achieve.

to see the object upclose then aperture is king.

only my opinion of course :)

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Take your time to get your head around things, before you make a purchase you might regret. The possibillities in astronomy land are asrtronomical...
First try to find out what you really want to do with your new hobby and than start looking for equipment expansion. Enjoy the scope you just got for now and see what it's shortcomings are from your perspective.

And  buy or loan books like 'Turn left at Orion' 

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