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Can’t see Jupiter through eyepiece

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#1 Saturn668

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Posted 07 September 2019 - 01:55 PM

I have the Explore Scientific ED80 Telescope and I was kind of saddened to realise that it came with a 1.25 inch eyepiece socket and a 90° diagonal and not an eyepiece itself. Luckily, I’d also ordered an Explore Scientific 52° Series 3mm Eyepiece. I pointed my telescope at Jupiter, put in my eyepiece and excitedly peered through it. Nothing. I repositioned the scope. Still nothing. I tried it with and without the diagonal, tried to focus it to no avail. It was all just black. While on the topic, looking at The Moon with this eyepiece resulted it a kind of pure white thing. You know the kind you’d see in a microscope where you would see what appeared to be hair (or lines) and those floaters you see on your eyes sometimes. I would appreciate it so much if someone could help. I’d been looking forward to this stargazing session for so long but I was only met with disappointment.

 

Note: I don’t have a finderscope but I have a guidescope. Also my mount does have GoTo capabilities but I currently don’t have sight of Polaris or enough stars to make an alignment.



#2 rolo

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Posted 07 September 2019 - 02:08 PM

Too much magnification (200x) with a 52* field makes for a tiny exit pupil. I would recommend a low power eyepiece to start, around 25mm or 30mm


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#3 bdyer22

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Posted 07 September 2019 - 02:14 PM

 What Rolo said.  You need to start off with a lower power EP (eyepiece) so you find things.  The finder gets you in the general vicinity, but you still need lower power to find the target.

 

Check out https://astronomy.to.../field_of_view/  it will give you an idea of what to expect with your scope and EPs

 

Nice scope :)


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#4 msl615

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Posted 07 September 2019 - 02:23 PM

Start in the day, so that you can point the scope at a far way building, tree, powerpole etc.  Then you can align your guidescope to get it very close.

 

Then, at night find a bright light, building etc somewhere in the distance in the main scope, and refine the guidescope alignment

 

Find the moon in the guidescope, and then in the scope with the lowest power ep you have, as noted above by other readers.  Focus on the moon to get it as sharp as possible.

 

 

Move the scope over to nearby Jupiter in the guidescope and you should be good to go!

 

Let us know how this works for you.

 

Mike



#5 Saturn668

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Posted 07 September 2019 - 02:26 PM

Thank you all for the help. The problem is, I don’t have a lower power eyepiece. But it looks like I’m going to have to buy one.


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#6 Barlowbill

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Posted 07 September 2019 - 02:40 PM

Plenty of inexpensive eps here on CN.  I use a 32mm and 25mm Plossl all the time for my finder ep.  Then go to a higher magnification.



#7 petert913

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Posted 07 September 2019 - 02:44 PM

Yes, you will find you use your lower power, wider field eyepieces much more than a 3mm.



#8 Napp

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Posted 07 September 2019 - 02:46 PM

You definitely want some lower power eyepieces.  I have an ED80.  Looks like you bought it for astrophotography.  It's an excellent scope for that.  It's also an excellent widefield visual scope.  You need some wider field lower power eyepieces to take advantage of that.  Wonderful scope for larger objects such as the Andromeda Galaxy, Milky Way star fields, Pleiades, Beehive, etc.  I have a 3mm eyepiece and it's the least used of all.


Edited by Napp, 07 September 2019 - 02:49 PM.


#9 nicoledoula

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Posted 07 September 2019 - 03:01 PM

Besides the need for other focal length EP's do we know this 3mm isn't one of the batch with an inverted lens, as discussed in another thread? Call ES to arrange a replacement. 



#10 Sleep Deprived

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Posted 07 September 2019 - 03:03 PM

You can probably get a low power EP for $10 or $20 (especially on the used market!) if all you want it for is to put something into your field of view.  The biggest 'pain' will be waiting for it to arrive!!!  After that, you may (or may not, of course) decide you want a better quality low power, wide field, eyepiece - aka: more $$$.  Or you may decide to get a mid-power EP instead.  At least if you get a cheap low power EP you won't feel like you've wasted a lot of money even if you decide to upgrade later on.  For the purpose of acquiring things in your FOV, cheap may be the way to start.



#11 sg6

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Posted 07 September 2019 - 03:05 PM

You need eyepieces.

Where are you?

Skywatcher 80ED's are more UK at present then US.

 

Does the scope come with rings - think so, and do the rings have 2 sticky up bits the other side to the dovetail?

If yes are they the same height, in effect do the tips sit parallel to the scope?

 

Suspect there may just be 1 pointy thing. If 2 you can sight along them to get a better chance of Jupiter.

 

Another is aim at Jupiter but without the eyepiece in and look down the diagonal, you should be able to see Jupiter (maybe a blurred Jupiter) then center that and drop the eyepiece in.

 

Will still warn that the 3mm is too much magnification and so too small a field of view to guarantee success. However you may get lucky.

 

Scope is f/7.5 so not fast. A reasonable plossl at 30mm area should do fine, Vixen NPL maybe. Alternatives are ES 52's at again 30mm. Paradigm at 25mm, Meade HD 60 at 25mm. Cost depends on location in the world.

 

Here the NPL's are something like £40, ES 52's around £58, Paradigms (Starguiders) around £50, Meade HD around £96 - think they are less in the US.

 

Jupiter should be reasonable at 80x that is a 7.5mm eyepiece - you will get 8mm and there are some at 6.5mm. Again Jupiter is low so magnification will magnify the general mess you are looking through.



#12 Saturn668

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Posted 08 September 2019 - 03:19 AM

Alright, so I live in Istanbul, Turkey in a highly light polluted area. Ordering anything from another country is a pain. It takes a long time and the 3mm eyepiece (which I ordered from the UK) got stuck in customs and we had to pay a tax. So I will attempt to find these in Turkey. My questions are for planetary, lunar and maybe deep sky observations what mm lenses should I have? Will Celestron lenses do? Also what can I use the 3mm eyepiece for? It hasn’t been a waste has it?



#13 bobzeq25

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Posted 08 September 2019 - 10:24 AM

Alright, so I live in Istanbul, Turkey in a highly light polluted area. Ordering anything from another country is a pain. It takes a long time and the 3mm eyepiece (which I ordered from the UK) got stuck in customs and we had to pay a tax. So I will attempt to find these in Turkey. My questions are for planetary, lunar and maybe deep sky observations what mm lenses should I have? Will Celestron lenses do? Also what can I use the 3mm eyepiece for? It hasn’t been a waste has it?

It helps a lot to know how these things work.  The large lens creates an image at the other end of the scope.  The eyepiece than magnifies that image.  The smaller the number on the eyepiece, the more it magnifies the image.

 

But a small number has some disadvantages.  Your eye has to be at just the right place.  The field of view is small, which makes finding things hard.  There's a limit to how much you can magnify the image without the quality of what your view being bad.  The bottom line is most people rarely use a number as small as 3mm.  It's a specialized tool for an expert, for certain situations.

 

So, what should you get for starting out?  Anything from 10mm to 30mm would be good, maybe you can find something like that locally.  10mm would be better for planetary, and closeups of the moon.   30mm would let you see the whole Moon, and is better for most DSOs.  Don't expect to see anything like the pictures of DSOs though (the Moon can come close), the camera is a completely different thing.



#14 The Ardent

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Posted 08 September 2019 - 10:56 AM

I’m disappointed that your friends in the astronomy club didn’t come over to help you celebrate first light with the new scope.

I have the Explore Scientific ED80 Telescope and I was kind of saddened to realise that it came with a 1.25 inch eyepiece socket.



#15 Hesiod

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Posted 08 September 2019 - 11:03 AM

At 160x the view should be rather dim, but not a "pure white thing": that was likely caused by the fact that were badly defocused.

Probably you have to rack out most of the drawtube to get the focus, but may get a close idea by aiming a target far on the horizon (e.g. ships).

As for the eyepieces' selection, a 10-12mm one (40-50x) is fine for "generic" observations of deep sky objects, even if should really travel to a darker site than Istanbul to see them (the interior of Anatolia would be perfect...I remember quite dark skies between Ankara and Cappadocia, and being on a rather dry plateau helps giving a crystal-clear sky).

If become adept to travels to dark sites, eyepieces in the 20-30mm range become really rewarding for huge, diffuse objects (especially if coupled with nebular filters).

If want to observe from Istanbul, your 3mm (160x) should be fine for planets, Moon, double stars, and some very bright deep sky objects (such as some planetary nebulae); you could add a 5mm eyepiece for more relaxed views (oncec learn how to observe, will find that can see the same details at lower magnification).

Celestron makes decent eyepieces (even if Explore Scientific ones are IMHO better value); giving the fact that you have a fast, short refractor, in your boots I would prefer to get "superwideangle" (60°-70°) or "ultrawideangle" (80°) eyepieces instead of "wideangle" (50°, e.g. the Plossl such as the OMNI by Celestron) because you can attain the same magnification and a (much) wider field of view


Edited by Hesiod, 08 September 2019 - 11:03 AM.


#16 CarrieTN

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Posted 11 September 2019 - 04:12 PM

Yes, we are kind of learning ourselves. Most people start out with some cheaper plossel Eyepieces like 35 deep sky and some smaller like 21mm. 17mm etc 

after you find out which magnifications you use most then you can get better eyepieces with the field of view you want

go to astronomy.tools. To help you

 

3mm would be like finding a needle in a haystack. Have to start with less magnification.

 

how we align our finder scope with the telescope is to do it when you see the moon during the day. Where we live hard to find anything far away and the moon works great using the lighted lines in the eyepieces to center




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