K-Tec

Attempting to Observe Jupiter/Venus

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92649 by conor-figgy
conor-figgy created the topic: Attempting to Observe Jupiter/Venus
Hey guys! I'm a relatively new amateur astronomer and tonight I tried to view Jupiter and Venus through my Celestron AstroMaster 130EQ. So, when I managed to get it in my scope this is what I saw:


Apologies for the crude ms paint drawing. The grey is the planet and the black is the structure of the mirror holder (as far as I can see). So, my questions are:

1) Why can I see the struts of the holder? I've observed the moon many times and it's never been in the way.
2) I couldn't get either planet into any recognisable focus, and ideas to why?

Thanks!

Please Log in to join the conversation.

  • astroado
  • astroado's Avatar
  • Visitor
  • Visitor
5 years 5 months ago #92650 by astroado
astroado replied the topic: Re: Attempting to Observe Jupiter/Venus
Not quite sure, new to this myself, what power eyepiece were you using? Did you use a barlow? To my untrained eye it looks like too much power.

Please Log in to join the conversation.

More
5 years 5 months ago #92651 by PaulWalsh
PaulWalsh replied the topic: Re: Attempting to Observe Jupiter/Venus
Hi this looks like the 'scope just needs to be focused. If you are using a barlow or an eyepiece with magnification that is too high you wont be able to get it any better then that.

Please Log in to join the conversation.

More
5 years 5 months ago #92652 by Coldfieldboundary
Coldfieldboundary replied the topic: Re: Attempting to Observe Jupiter/Venus
your eyepiece is not in focus, so turn that wheel to turn it in/out until you get focus. Maybe you cannot reach focus, then your distance to move it in/out is too small, but then your eyepiece is not suitable on your scope.

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92653 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
I've tried it with a 20mm, 10mm and 7mm eyepiece and all with/without a barlow lens and I got relatively the same thing.

Please Log in to join the conversation.

More
5 years 5 months ago - 5 years 5 months ago #92654 by dave_lillis
dave_lillis replied the topic: Re: Attempting to Observe Jupiter/Venus
have you tried focusing on the moon and then moving the scope to jupiter without changing focus,
On bigger dobs, you do get the vains holding up th secondary as spikes on the brightest stars.

Dave L. on facebook , See my images in flickr
IFAS Rep. Shannonside Astronomy Club (Limerick)

Carrying around my 20" obsession is going to kill me,
but what a way to go. :)
+ 12"LX200, MK67, Meade2045, 4"refractor
Last Edit: 5 years 5 months ago by dave_lillis.

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92655 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Hmm, I'll try that tonight if the moon isn't too bright!

Please Log in to join the conversation.

More
5 years 5 months ago #92656 by Nerro
Nerro replied the topic: Re: Attempting to Observe Jupiter/Venus
Yes it looks like that the object is out of focus.or your eyepieces can't reach focus, this part is highly unlikely as your scope is designed for visual use.when I had my Newtonian OTA I needed an extension tube to be able to use it for visual.

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92657 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Ah ok, I tried my best to focus it but got nowhere. I'll try again tonight but is there anything in particular I should be doing/looking out for?

Please Log in to join the conversation.

More
5 years 5 months ago #92658 by Nerro
Nerro replied the topic: Re: Attempting to Observe Jupiter/Venus
What sort of eyepieces are you using?if you have heavier ones then maybe your focuser is too loose and literally can't focus as cant move the EP.just turn your focus wheels back and forth and look if the EP moves all the way up having your tube horizontally and focuser fasing up with your heaviest EP in it.
If it doesn't go all the way up it means it's too loose and you will need to tighten it.

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92659 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
I have:
- Celestron 10mm eyepiece
- Celestron 20mm erecting eyepiece
- Celestron 6mm eyepiece
- Celestron Omni 2x Barlow Lens

Just checked my focuser, seems to be working just fine.

Please Log in to join the conversation.

More
5 years 5 months ago #92660 by Nerro
Nerro replied the topic: Re: Attempting to Observe Jupiter/Venus
Well all of them are fairly light so it shouldn't be a problem.try to focus on the moon with your 20mm as Dave suggested until you will get crisp view and then slew to Jupiter.it should be already focused and you should clearly see it along with its moons.
Now if you will see the spider vanes then your scope is way out of collimation and i mean way off as I don't know what else could be wrong...

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92662 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Ok, I'll do that hopefully tonight depending on cloud coverage and then report back here. Thanks!

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92666 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Nope, same story. I got some great views of the moon but both Jupiter and Venus looked like my original image.

Please Log in to join the conversation.

More
5 years 5 months ago #92669 by dave_lillis
dave_lillis replied the topic: Re: Attempting to Observe Jupiter/Venus
I have to say, Im having trouble interpreting your image, do you mean you see a circular disk with zero details and 4 lines or are you seeing a fuzzy jupiter with almost no detail and 4 lines ?
If the bright illumination/planet image in the center perfectly center or is it oblong/lobsided.

Dave L. on facebook , See my images in flickr
IFAS Rep. Shannonside Astronomy Club (Limerick)

Carrying around my 20" obsession is going to kill me,
but what a way to go. :)
+ 12"LX200, MK67, Meade2045, 4"refractor

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago - 5 years 5 months ago #92670 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Oh sorry, I see a circular disc with no detail (grey) and in the middle of this is a black disc which has four lines coming out of it. The black disc is, as far as I know, the mirror in the centre of my tube, specifically the mirror which reflects the image into the eyepiece. The planet isn't distorted/oblong I'm pretty sure.
Last Edit: 5 years 5 months ago by conor-figgy.

Please Log in to join the conversation.

More
5 years 5 months ago #92677 by mykc
mykc replied the topic: Re: Attempting to Observe Jupiter/Venus
Very odd. Your drawing and description match what you would see if the focusing was way off, and yet you get good views of the moon, which would require the same focus position! Can you make out the details on the lunar surface clearly? This must be very frustrating, so it might be time to make contact with another stargazer in your area. Whereabouts are you located?

Mike

Celestron 280 mm f/10 SCT
CG-5 mount
Toolbox full of bits n' bobs
Thermal underwear

Please Log in to join the conversation.

More
5 years 5 months ago - 5 years 5 months ago #92681 by dave_lillis
dave_lillis replied the topic: Re: Attempting to Observe Jupiter/Venus
yea, definitely sounds like it's out of focus, maybe there is a loose mirror somewhere and it's shifting when you move the scope, you need someone experienced to look at it for you.

Dave L. on facebook , See my images in flickr
IFAS Rep. Shannonside Astronomy Club (Limerick)

Carrying around my 20" obsession is going to kill me,
but what a way to go. :)
+ 12"LX200, MK67, Meade2045, 4"refractor
Last Edit: 5 years 5 months ago by dave_lillis.

Please Log in to join the conversation.

More
5 years 5 months ago #92694 by Graham
Graham replied the topic: Re: Attempting to Observe Jupiter/Venus
Sounds like colimination

In a misaligned scope, the star is out of focus and will appear as a doughnut shape with a dark center. If your telescope is misaligned, this dark patch will be perfectly centralised within the bright ring. This is actually the shadow cast by the secondary mirror, and you may also see the spider veins (as in the figure below). When the optics are in need of alignment the dark patch will be off center.

Source

If it is collimated then perhaps it is collimated with mirror travelling too far up the tube?

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92697 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Ahh, awesome... thanks guys! Yeah that's pretty much what I can see when trying to view the planets, but not the moon for some reason... I'm from Kilkenny but got to college in Dublin.

So, collimation it is then.

Please Log in to join the conversation.

More
5 years 5 months ago #92698 by Calibos
Calibos replied the topic: Re: Attempting to Observe Jupiter/Venus
Not so fast. Its unlikely anything to do with collimation. If you are seeing anything like your diagram or that photo you are looking at a grossly out of focus image.

Are you using the eyepieces that came with the scope?

I read that the scope has some kind of correct image prism thingie for Terrestrial viewing. Can this be removed? It might be preventing you reaching focus for celestial objects.

You do realise that even with a barlowed 7mm giving you about 150x that Jupiter in the eyepiece wont look much bigger than the full moon looks to your naked eye when you look up at it. ie. Are you sure you aren't bypassing perfect focus when the image of Jupiter is at its smallest and sharpest because you are saying to yourself, "Nah, shouldn't be that small!" 'Fraid it is mate :D

Keith D.

16" Meade Lightbridge Truss Dobsonian with Servocat Tracking/GOTO
Ethos 3.7sx,6,8,10,13,17,21mm
Nagler 31mm

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92700 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Yeah, I'm using the three eyepieces that come standard and the barlow was bought by the previous owner.

I'll try look into this correct image prism.

Actually, you might have something there... I don't think I actually used the 6mm and the barlow together as I thought it would be too much, whoops. Hmm, perhaps I was trying to view it with an underpowered eyepiece and therefore went way way past the focus point. Well, tonight shall hopefully tell! Cheers!

Please Log in to join the conversation.

More
5 years 5 months ago - 5 years 5 months ago #92708 by dave_lillis
dave_lillis replied the topic: Re: Attempting to Observe Jupiter/Venus
Your sharpest image will always be with the longest mm eyepiece, leave the barlows out, it's also the lowest power, so the smallest image. If that doesnt work for you, then the higher power eyepieces are only going to be worse, presuming they all reach focus.
If you are seeing exactly the image from 4 posts ago, then your eyepiece is not focused, maybe your primary mirror is too far down the tube ?.
if it is what you're seeing then your moon images must be out of focus aswell and look mushy/blurry/soft.

In that image from 4 posts ago, it is slightly out of collimation, but you still be able to see some sort of image when focused. What do they brightest stars look like through the lowest power eyepiece when focused , are they dougnnuts?, flaired with a fan like comet tail, or like boiling dots/points ?

Dave L. on facebook , See my images in flickr
IFAS Rep. Shannonside Astronomy Club (Limerick)

Carrying around my 20" obsession is going to kill me,
but what a way to go. :)
+ 12"LX200, MK67, Meade2045, 4"refractor
Last Edit: 5 years 5 months ago by dave_lillis.

Please Log in to join the conversation.

  • conor-figgy
  • conor-figgy's Avatar Topic Author
  • Offline
  • Proto Star
  • Proto Star
More
5 years 5 months ago #92722 by conor-figgy
conor-figgy replied the topic: Re: Attempting to Observe Jupiter/Venus
Just back in, when I tried to observe a star it looked like the image posted earlier and the boiling dots/points as I focused "out" if you know what I mean. So, other than when I observe the moon; I can see the spider vanes and mirror shadow, again like the image posted previously.

I don't have a laser collimator, neither do I know any other amateur astronomers around where I live. Should I just wait until I get a chance to bring it to someone knowledgeable or invest in a laser collimator and learn how to do it myself?

Please Log in to join the conversation.

More
5 years 5 months ago - 5 years 5 months ago #92729 by dave_lillis
dave_lillis replied the topic: Re: Attempting to Observe Jupiter/Venus

conor-figgy wrote: tried to observe a star it looked like the image posted earlier and the boiling dots/points as I focused "out" if you know what I mean.

hmm, interesting, so when you get the boiling point for the star, thats the focus position and that'll be the focus position for every object in the sky with that eyepiece obviously. i'm kinda wondering are you thinking that the scope is focused when the focuser tube is fully racked in, by what youre saying.
The boiling is normal unfortunately, the atmosphere and thermals in the scope causes it.
IF you are seeing stars like that, then there is nothing wrong. Spider vains are normal on the brighter stars when focused, nothing you can do about it. If you view of Jupiter is very small, you could get spider vains there aswell.
If you move the scope to Jupiter and all you see is a fuzzy disk without changing focus or eyepeice, then I'm left wondering is this a "unrealistic expectation" thing going on here,

Dave L. on facebook , See my images in flickr
IFAS Rep. Shannonside Astronomy Club (Limerick)

Carrying around my 20" obsession is going to kill me,
but what a way to go. :)
+ 12"LX200, MK67, Meade2045, 4"refractor
Last Edit: 5 years 5 months ago by dave_lillis.

Please Log in to join the conversation.

Time to create page: 0.228 seconds
Powered by Kunena Forum