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What am I doing wrong

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Hello. New member here. My 4 1/2 y/o loves everything about the universe. When he gets TV time he wants to watch the Discovery Channels How the Universe Works. He's even made a Cassini probe out of Tinker Toys. So of coarse we started looking to the sky and see what we could see. First with just our eyes and then we started using a 20-60x spotting scope that I have for target shooting. Finally we stepped up to our first telescope. A Celestron Asstromaster 114eq. Last night the moon was very bright and we were able to see it well. Mars was the only planet out, that wasn't too far after bedtime, so I focussed in on it with the 20mm eyepiece. Here's where my problem came. I could not get a good sight picture (probably not the proper term) of Mars. It was either small and blooming or when I got it big enough there was a shadow of the secondary mirror. We saw Mars better with my spotting scope. After the kids were in bed I found Jupiter and Saturn and had the same effect. We live in Southern New Hampshire. What am I doing wrong? I'd appreciate help. Thank you.

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Did you get any other eyepieces with the scope, because you need at

least a 10mm to get anything from Mars, and the seeing needs to be very

good, Mars will look small, but if you observe it for a while your eyes will

get used to the view, when you focus make sure the image gets smaller 

not bigger, the bigger it gets the more out of focus it will be, Mars is not

a real Wow factor, but Saturn is, if you get the chance observe it, it will

help you learn to focus, as the rings of Saturn come into view as you turn

the focus-er, Saturn is almost as bright as Mars and will be to your left,

but it will be later when it is in view, good luck and Enjoy! 

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Its a common mistake. Most people see pictures of the planets (mostly Jupiter, Saturn and Mars with lots of details) and think thats what I will see in my telescope. This is often not true, especially in smaller telescopes. The planets, even the biggest ones, are very small in the sky. In reality Mars is smaller than the Earth but because of its distance it will look very very small. So small that in some telescopes, if you don't know what you are looking for, you could easily mistake it for a bright red/orange star. In my 114mm I can barely make out the 2 major bands on Jupiter with my 10mm EP and  thats HUGE compared to Mars. Also local light pollution plays a factor too.

For Mars when you get it in focus it should have tight edges and be quite small. You will not be able to see any detail on it, especially with the moon out. You might be able to get some slight detail if you were at new moon and a dark site. When you see it get large but see the secondary's shadow that means you are very out of focus. If you focus on the moon and its details you should be pretty close to if not in focus for viewing Mars. Another thiing that could make it look not in focus would be the poor seeing conditions in your area at that time. This is do to moisture in the air and/or turbulance in the atmosphere.

Do get discouraged even the in the larger telescopes Mars is a very small target. To get some ideas of what you will see go to the sketching section and look for hand drawn sketches of Mars. This will give you a good clue as to what you will see or what is required to get the large amount of details.

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Great to see a dad and his son enjoying something together.

Mars is renowned for being 'difficult', I've only had a handful of iffy views with the 200P since I picked it up.

The proximity of a bright Moon will kill it.

From what you say in #1, you were waaaay out of focus, but if you have a selection, try to get a decent blob with your 20mm 'bout the size of a zit on a flea, and then try a shorter EP if you have one, refocusing along the way.

You will never see the detail that is shown in AP images, nor will I.



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Hi Astrodad and welcome to SGL.

You don't say but do you have a dew shield on your scope? This not only helps with delaying/preventing dew from building up on your mirrors but also cuts out any stray light from entering the tube and effecting the contrast of your image.

How to collimate a Newtonian telescope:




Edited by southerndiver357
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Another thing that could make it look not in focus would be the poor seeing conditions in your area at that time. This is do to moisture in the air and/or turbulence in the atmosphere.

Before you go jumping in to collimating and blaming the 'scope, this is a big possibility. I haven't had a good night's viewing of Mars this year yet. Nothing wrong with the 'scope, just that every time I've had the opportunity to look at Mars the seeing conditions have been poor. Bubbling, boiling, fuzzy mess!  :grin:

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Same as bingevader.

Mars is going to be a some what hard target to nail. you may get a better chance with a webcam fitted to the telescope,

and using your barlow. 

That pesky moon is a lovely sight but it can be our downfall to making things harder to see, less stars in the sky

because of the moons glow. 

jupiter is a nice target, place your BARLOW into the focuser then pop in your 25mm eyepiece, you should see jupiter and a few of its moons.

If you wait and keep watching mars you will notice that another star like object appears down to the left of mars, This is Saturn.

with your BARLOW in your focuser add your 10mm eyepiece and have a look, you will need to be gentle on the focuser but you should see

Saturn and its rings. 

its a shame Orion is low that would have been a lovely target with your 25mm eyepiece.

Great to see father and son enjoying a hobby together 

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mars often looks like a small fuzzy blob of jelly bouncing around in your eyepiece
don't get disheartened this is a very tough hobby to get into with steep learning curves but well worth the effort when you get the WOW moment

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