Jump to content

SkySurveyBanner.jpg.21855908fce40597655603b6c9af720d.jpg

Celestron 114eq - Wobbling


Recommended Posts

Hi All,

I have just bought a used one of these as a beginner.

I've got the DSLR mount which I've used and I'm struggling with it staying still when trying to photograph planets. I focus on Jupiter and it moves out of view. The screws are extremely tight.

I've noticed on the stand the thing wobbles and I am wondering if its me or a dodgy stand.

Any help would be appreciated.

Link to comment
Share on other sites

I can't identify the exact mount from "Celestron 114 EQ" but I have to point out that such kits are generally supplied with the cheapest and most flimsy mount that will hold the telescope up and not generate immediate complaints.

Ideally you want a more substantial mount like the EQ-5 or HEQ-5 to hold your telescope while you try to image planets with it.  And you would get better results with a dedicated planetary imaging astro camera.   I fear that astro imaging, whether planetary or deep space, can be a money pit.

And if you have got that far, you may that you can't get focus with a DSLR without modifying your telescope.

Edited by Cosmic Geoff
  • Like 1
Link to comment
Share on other sites

Camera is definitely moving slightly on one of the directions (sorry still not able to remember the two) as It goes off of the screen on the DSLR and with long exposure all I get is a white line!

The wobble is at the section where you do latitude, please dont second guess.

I shall do a video of this over the weekend with it being of no use with the cloud and add to the post. 

I'm convinced the thing is too heavy for anything other than moon watching. 

Link to comment
Share on other sites

36 minutes ago, Deason said:

Camera is definitely moving slightly on one of the directions (sorry still not able to remember the two) as It goes off of the screen on the DSLR and with long exposure all I get is a white line!

Is this a powered mount? If not, the Earth's rotation will cause objects to move through the camera's field over the course of a few minutes.  Planetary imaging requires exposures measured in milliseconds.   I doubt very much that long exposures are feasible with your outfit.

Link to comment
Share on other sites

Hi Deason

I think the reason your stars appear as white lines is because, as Geoff says,  the mount doesn't have a motor on it to allow the mount to follow the stars as they appear to move across the sky.

You'll have to experiment with the longest exposure that gives round stars.

Michael 

Link to comment
Share on other sites

1 hour ago, michael8554 said:

Hi Deason

I think the reason your stars appear as white lines is because, as Geoff says,  the mount doesn't have a motor on it to allow the mount to follow the stars as they appear to move across the sky.

You'll have to experiment with the longest exposure that gives round stars.

Michael 

 

I did wonder if my perception of how quickly we orbit was why this is happening. How quick you talking though? Its like the telescope is moving quickly to me (I'll record at some point). 

I can hold the camera in place and it doesn't move (but obviously wobbles). 

Video here.

 

 

Link to comment
Share on other sites

I can't tell anything from your video.  If you look up some elementary astronomy texts, that will tell you how quickly objects appear to move across the sky in response to the Earth's rotation. Or you can see it for yourself if you put an eyepiece in the telescope, aim it at a star or other object and just watch without touching anything.

Link to comment
Share on other sites

From the video the mount looks like an EQ1. These are designed for visual and not astrophotography. Even so they are basic and usually give a “wobbly” experienced. I did own one. Yours doesn’t seem to have a motor drive which you would need to follow the rotation of the earth. You can’t manually do it accurately. You can get a simple and cheap motor drive for an EQ1 but again it’s designed for visual only. 

How fast an object moves in the eyepiece depends on the magnification. At very low power and by eye, you hardly notice it. At high magnification (like you’d need for planets) it’s obvious. Here’s a little simple smartphone animation that I did a while back that shows Jupiter in the eyepiece of a Dobsonian with no tracking. As you can see it won’t stay in view for long.

 

Edited by PeterStudz
  • Like 1
Link to comment
Share on other sites

The celestial equator appears to move 15 seconds of arc per second of time. Less if you're looking at something towards the celestial poles, but planets are always fairly close to the equator. The apparent size of Jupiter is between 30 and 60 arcseconds (roughly), so it will appear to move fairly fast on an undriven mount.

If it's the Astromaster 114eq (and it looks like it) then sadly you've bought a bit of a stinker. The telescope optics, eyepieces, and mount are all dubious. If you're new to stargazing as a whole, focus on visual observing, and within that focus on deep sky viewing which is done at low magnifications which won't show the optical flaws so much. I would buy a 32 mm Plossl to help with finding things but I wouldn't spend any more on it. Understand that a better telescope could be a lot easier and less frustrating to use.

To image the planets get your DSLR to take a video as the planet drifts across the view then process the frames. You can probably get a final image with some identifiable detail but do not expect very good results with this telescope.

Link to comment
Share on other sites

15 hours ago, PeterStudz said:

From the video the mount looks like an EQ1. These are designed for visual and not astrophotography. Even so they are basic and usually give a “wobbly” experienced. I did own one. Yours doesn’t seem to have a motor drive which you would need to follow the rotation of the earth. You can’t manually do it accurately. You can get a simple and cheap motor drive for an EQ1 but again it’s designed for visual only. 

How fast an object moves in the eyepiece depends on the magnification. At very low power and by eye, you hardly notice it. At high magnification (like you’d need for planets) it’s obvious. Here’s a little simple smartphone animation that I did a while back that shows Jupiter in the eyepiece of a Dobsonian with no tracking. As you can see it won’t stay in view for long.

 

Interesting, this is about what I am seeing in my camera so thank you! 

This is all good learning, the telescope was only purchased to get used to all of these sorts of things. 

 

  • Thanks 1
Link to comment
Share on other sites

On 16/12/2022 at 14:14, Deason said:

Hi All,

I have just bought a used one of these as a beginner.

I've got the DSLR mount which I've used and I'm struggling with it staying still when trying to photograph planets. I focus on Jupiter and it moves out of view. The screws are extremely tight.

I've noticed on the stand the thing wobbles and I am wondering if its me or a dodgy stand.

Any help would be appreciated.

You have this kit...

https://www.celestron.com/products/astromaster-114eq-telescope

The mount is an EQ-1, the smallest and least supportive equatorial mount on the planet.  The mount is only for the smallest of telescopes, like this Celestron C90 Maksutov...

kit5b.jpg.bab41a6df2e1853cccb22e4f7f51a64d.jpg

Since round 2000, the manufacturers have combined telescopes that are too large with mounts that are too small, to attract the eye in the case of the "AstroMaster" series, in anodised orange and excessive plastic trimmings.

The telescope that you have there is not a Newtonian, oh no.  It is a catadioptric-reflector rather, just like my Celestron "PowerSeeker" 127mm...

OEM5b.jpg.7435f1a50006ccac915496222425b674.jpg

My EQ-1 mount came with that telescope, but I do not use that wee mount with that large of a telescope, nor is your "AstroMaster" EQ-1 suitable for the 114mm catadioptric-reflector; just adequate for visual, but not at all for astro-photography.  But cheer up, as you may certainly take photographs with the telescope itself.  You will need at least an EQ3-class mount, like the EQ3-2, if not an EQ-5 which would be ideal, support-wise.

Both of our reflectors appear as Newtonians, but in the end they are not.  Colloquially, both are known as "Bird Jones" telescopes. A catadioptric-reflector, or "Bird Jones", utilises both lenses and mirrors within the optical-train of the telescope...

catadioptric.jpg.cf26d958c68e507d8f1cea71bf8e2ae5.jpg

...the doublet-lens on the left, the spherical primary-mirror on the right.  The lens is placed here at the end of the draw-tube of the focusser...

doublet9d.jpg.0405f160f887408b5bfb716d0d8e502f.jpg

The other end is where an eyepiece is inserted; note the thumb-screws.  The lens acts as a barlow, doubling the focal-length of the telescope.  It is also reputed to correct for spherical aberration, to correct the sphere itself.  My 127mm is at f/8, but its sphere is at a native f/4 or thereabouts.  Your 114mm is at f/8.8, and its sphere at f/4.4 or so.  Indeed, without the lens installed, both of our telescopes are as Newtonians, bad ones at that with their spheres, however they cannot function as classical Newtonians when lens-less. 

For best performance, collimating both requires removal of the lens-cell from the optical train...

doublet9a.jpg.16a33f5cc133ec384a07bffab0e2c447.jpg

After collimation, the lens-cell is re-installed.  Many take the lens out of its cell via its slotted retaining-ring.  That is incorrect.  Rather, the entire cell containing the lens is removed, as shown.  That way, the lens isn't soiled, nor flipped out of order.  The cell is removed with a tool via these two holes circled in yellow...

96392770_doubletcorrector4b.jpg.498ca534bbf40057577c59c5376adc74.jpg

I made my own tool with oak and nails.  Again, do not remove the lens from its cell, ever; unless you'd like to blacken its edge round, to improve contrast and reduce light-scattering...

doublet3e.jpg.076e6a5b6fbfe47d3b356b54b4d0bb83.jpg

Edited by Alan64
Link to comment
Share on other sites

On 18/12/2022 at 07:09, Deason said:

Interesting, this is about what I am seeing in my camera so thank you! 

This is all good learning, the telescope was only purchased to get used to all of these sorts of things.

You could try getting one of these to help track the stars https://www.celestron.com/products/astromaster-powerseeker-motor-drive

I have the 130EQ and the mount looks similar so the only way to settle the wobble is hang weights to the mount (I used milk bottles filled with water). The plastic tray is too flimsy so dont hang on that. The other thing to do is set a delay on the camera before it captures an image. This will allow the wobble to settle once you have pressed the shutter. Using a remote control also helps reduce the wobble.

EDIT: If you have the Astromaster series, it probably doesnt have the additional lens in the drawtube (my 130eq doesnt) so not a birdjones. And dont be put off by comments that its optics are bad etc. See my signature link to see what kind of images you can get from such a scope. But you do need a better mount to get these!

Good luck!

Edited by AstroMuni
Link to comment
Share on other sites

I did get the little motor for my old EQ1 as mentioned by @AstroMuni. And it’s been the best bit of Astro kit I’ve purchased. Certainly for the price. Visually it’ll let you track objects for a good 10 minutes. And once you have it tracking there’s no need to touch anything which (as long as it’s not too windy!) means no more wobbles.

I also used the motor to take simple smartphone snaps. At low-ish magnification I found that I could get about 30sec exposures without star trailing. This allowed pictures of the bright DSO and even the brighter galaxies. A lot of fun and it teaches you the basics. 

  • Like 1
Link to comment
Share on other sites

1 hour ago, PeterStudz said:

I did get the little motor for my old EQ1 as mentioned by @AstroMuni. And it’s been the best bit of Astro kit I’ve purchased. Certainly for the price. Visually it’ll let you track objects for a good 10 minutes. And once you have it tracking there’s no need to touch anything which (as long as it’s not too windy!) means no more wobbles.

I also used the motor to take simple smartphone snaps. At low-ish magnification I found that I could get about 30sec exposures without star trailing. This allowed pictures of the bright DSO and even the brighter galaxies. A lot of fun and it teaches you the basics. 

Thats exactly how I started my journey 🙂 but only tried lunar & planetary imaging with my phone.

I did find that the motor got in the way in certain positions on my Astromaster 130, so thats one thing for the OP to watch out for!

  • Like 1
Link to comment
Share on other sites

Just now, AstroMuni said:

Thats exactly how I started my journey 🙂 but only tried lunar & planetary imaging with my phone.

I did find that the motor got in the way in certain positions on my Astromaster 130, so thats one thing for the OP to watch out for!

Yes, that’s a good point. It’s not that well thought out and can get in the way in certain positions. But at home, as my view from my garden is E-SE-SW (house blocks the north) I mounted it on the other side of the mount to  “normal” and never had a problem from them on. 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.