Stargazing I Am Cursed Ack Fi My New Telescope hates me

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The discussion revolves around troubleshooting issues with a new telescope that is producing fuzzy images of celestial objects, particularly Jupiter. The user has attempted to collimate the telescope but continues to see spider vanes in the eyepiece, indicating potential misalignment or installation errors. Suggestions include checking the alignment of the secondary mirror and ensuring the focuser is correctly installed, as improper installation could prevent focusing. The user is also advised to perform a star test to assess collimation and consider reverting to the original focuser if problems persist. Overall, the conversation emphasizes the importance of proper setup and alignment for optimal telescope performance.
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Step 1:take telescope out of box and assemble according to instructions.

2. Install Crayford focuser.

3. Collimate to the best of my ability/knowledge

4. Take scope outside and point at Jupiter

5. Become enfuriated because for the 2nd night in a row, all I have been able to see is a fuzzy @#$!ing disc with crosshairs over it...WHY CAN I SEE THE SPIDER VANES?!

I going to go hit my head against the wall for awhile.

Casey
 
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You can see the spider vanes in the eyepiece? :bugeye: This doesn't even sound like a collimation issue; it sounds more like something is installed completely incorrectly. How are you attempting to collimate it?

- Warren
 
OK. Let's try this. Take your scope outside in the daytime, and look at a distant object. If you cannot bring it into focus, adjust the position of the primary until you can see it (a distant tree-line should do). Then, without racking the position of the primary in or out, tweak the primary screws to get the mirror colimnated with the secondary. This should get you close enough so you can see something on your next outing and get you motivated to tweak the alignment of your scope's mirrors so that you can see more.
 
chroot said:
You can see the spider vanes in the eyepiece? :bugeye: This doesn't even sound like a collimation issue; it sounds more like something is installed completely incorrectly. How are you attempting to collimate it?

- Warren

I know, but I can see them!

turbo-1 said:
OK. Let's try this. Take your scope outside in the daytime, and look at a distant object. If you cannot bring it into focus, adjust the position of the primary until you can see it (a distant tree-line should do). Then, without racking the position of the primary in or out, tweak the primary screws to get the mirror colimnated with the secondary. This should get you close enough so you can see something on your next outing and get you motivated to tweak the alignment of your scope's mirrors so that you can see more.

I already took it out today and focused in on a blinking light about 1/4 of a mile away. I could see the vanes then too. I alligned the Primary and secondary with each other I think. I mean, I adjusted the 2ndary so that I could see all of the primary in it.

Then I adjusted the tilt of the primary until the 'dot' on the sight tube was inside of the center-mark on the primary.
 
I'm not sure about your collimation issues, but unless you are somewhere very south, Jupiter is going to be a fuzzy mess because it is so low on the horizon.
 
Maybe I am just a D-bag. The Orion Tech guy insists that it must be diffraction spikes...so maybe I just don't know what I am doing yet... I am going to Google around and see if I can find a picture of what diffraction spikes would look like...
 
I don't know. I have not had a good viewing night, but I think the spikes I was seeing were black. Thus, I thought they were the vanes?
 
Can you... take some pictures of the inside of the scope for us? And let us take a look at how you've set up the critical pieces?

Do you have an astronomy club nearby whom you could contact for in-person help?

- Warren
 
  • #10
There is a star test for collimation - point at a medium-bright (it must not be very bright) star, use a high magnification, and see if the star makes concentric circles. Then slowly focus in and out and see if it makes big concentric circles when going out of focus. If the circles are not concentric, the collimation is off.
 
  • #11
chroot said:
Can you... take some pictures of the inside of the scope for us? And let us take a look at how you've set up the critical pieces?

Do you have an astronomy club nearby whom you could contact for in-person help?

- Warren

I'll try that out. I did not set up the inner workings though. It came with the optical tube nearly complete. All I had to do was install the new focuser and the tube rings.
 
  • #12
Tough to tell, but it looks in the video like one of the supports for the secondary is twisted, making it face into the telescope. Make sure they present as small a cross-section as they can to the inside of the scope.
 
  • #13
Russ is right. It looks like the vanes of the spider are not parallel to the light path. That will cause problems. If so, you need to loosen the nuts fastening the spider to the tube, and make sure to re-tension them gently while making sure that the flats of the vanes are parallel to the tube.

Then, make sure that your primary is aimed at your secondary, and fine-tune the secondary, if necessary, then tweak the primary again until your scope can do the inside-and-outside of focus star test. A star inside or outside of focus should present a nice symmetrical disk that resolves cleanly to a point at focus.
 
  • #14
Yeah, the spider vanes look to be in pretty bad shape. You might even have trouble centering the secondary over your primary with the vanes bent and twisted, which will pretty much prevent you from ever getting good collimation.

- Warren
 
  • #16
I guess I would have thought they could rotate relatively easily. Do you have the screws too tight?
 
  • #17
I am not sure what "too" tight is. I mean, I think they are within reason. I was able to rotate them somewhat and then I held the vanes as parallel to the optical tube as possible and slowly tightened the four thumbscrews. The video in post#16 is what they look like now, after attempting to fix. It looks like an improvement, but I e-mailed Orion anyway to see what they would be willing to do.

I don't want to pay to ship anything back, but if they are willing to just send me four new vanes (they look cheap enough) I could reinstall them. If not, I am sure I could fabricate some new ones.

~Casey
 
  • #18
Agree with turbo, loosen the vane nuts while focused on a distant point light source, then slowly tighten them. You should not see the vanes, just diffraction spikes from off center light sources - and these should be subtle. If you can see the vanes, your secondary mirror is not at the proper distance from the primary. Do you have two sets of holes for the vanes? [one for prime plane photography and one for visual]
 
  • #19
Chronos said:
Agree with turbo, loosen the vane nuts while focused on a distant point light source, then slowly tighten them. You should not see the vanes, just diffraction spikes from off center light sources - and these should be subtle. If you can see the vanes, your secondary mirror is not at the proper distance from the primary. Do you have two sets of holes for the vanes? [one for prime plane photography and one for visual?]

I will check tomorrow. Like I said, the tube came assembled, so I am not sure. These "spikes" certainly are not subtle.

Casey
 
  • #20
  • #21
Orion is sending me a whole new 2ndary mirror assembly. This will determine whether it is the scope or just me. :/
 
  • #22
Good work! Orion makes good instruments and usually stands behind them. If you continue to have problems with it, bug them incessantly until it's resolved!

- Warren
 
  • #23
I'm going to go ahead and ask a stupid question - Are you sure you're focusing correctly? Through an eyepiece, the only way I can see the spider vanes is if I am way out of focus. Do you see the same problem with every eyepiece you have? Can you tell us what eyepieces you are using?
 
  • #24
WMGoBuffs said:
I'm going to go ahead and ask a stupid question - Are you sure you're focusing correctly? Through an eyepiece, the only way I can see the spider vanes is if I am way out of focus. Do you see the same problem with every eyepiece you have? Can you tell us what eyepieces you are using?

I am only using the 25 and 10mm that came with the scope. I did install a new Crayford focuser that came along as an upgrade; however, it was supposed to be just a "drop in" replacement. And that is what I did: removed 4 screws from old focuser; remove old focuser; replace with new focuse (in same orientation); replace 4 screws.

Casey

p.s. not a stupid question. This is pretty much the first scope I have ever owned:wink:
 
  • #25
If you compare the two focusers, do they each hold the eyepieces a similar distance from the side of the telescope's tube?

Is it possible that you were accidentally shipped the wrong focuser? Does the telescope function properly with the other (stock) focuser?

- Warren
 
  • #26
chroot said:
If you compare the two focusers, do they each hold the eyepieces a similar distance from the side of the telescope's tube?

Is it possible that you were accidentally shipped the wrong focuser? Does the telescope function properly with the other (stock) focuser?

- Warren

You, I had thought of swaooing them back out, but shrugged it off...I think I'll go try that now for kicks.

Thanks,
Casey
 
  • #27
Can someone answer this?

Should the focuser be all the way in or out while collimating...or at the "most used" position?

I know it would be ideal to have the scope collimated at every position, but it seems that that might not be possible.
 
  • #28
"Collimation" means an alignment of the optical axis of the telescope. When a telescope is collimated, it is collimated at every position of the focuser (assuming the focuser is properly installed and is on-axis).

Collimation with a star is usually done near focus (just inside or just outside focus), using the symmetry of the Airy disc as a guide.

- Warren
 
  • #29
chroot said:
"Collimation" means an alignment of the optical axis of the telescope. When a telescope is collimated, it is collimated at every position of the focuser (assuming the focuser is properly installed and is on-axis).

Collimation with a star is usually done near focus (just inside or just outside focus), using the symmetry of the Airy disc as a guide.

- Warren
Right. I just meant if I am outside right now collimating my scope, should I compress or extend the focuser tube? If everything was perfect I know that the little "dot" would stay centered "in" the little "ring" perfectly; however, I am experiencing some variance.

I am still waiting for new parts, but I am trying to elliminate all other possibilities.

Casey

Question #2: I am looking through the scope at a chimney at least a 1/4 mile away (it is day light here); I can get focused pretty well at low mag (25mm eyepiece), but at high (10mm) I can not bring it to focus.

Is that normal?
 
  • #30
Hmm. You're going to need pretty high power to do proper star-test collimation. If your focuser's range prevents you from bringing a 10 mm eyepiece to focus, then the focuser is not appropriate for your telescope. I strongly advise you to try to stock focuser.

- Warren
 
  • #31
chroot said:
Hmm. You're going to need pretty high power to do proper star-test collimation. If your focuser's range prevents you from bringing a 10 mm eyepiece to focus, then the focuser is not appropriate for your telescope. I strongly advise you to try to stock focuser.

- Warren

So not being able to bring this chimney into focus is not normal then?

Casey
 
  • #32
1/4 mile shouldn't be too close to focus. You might be near the end of the travel of the focuser, but it should be possible to focus the telescope on an object 1/4 mile away. Again, please try the stock focuser and tell us what happens in the same situation.

- Warren
 
  • #33
I guess I missed the part about changing-out the focuser. There are several things that can go wrong there and a good rule of thumb for any new device you buy (whether it be your car, your computer, etc.) is to get it working stock before trying to modify it.
 
  • #34
chroot said:
"Collimation" means an alignment of the optical axis of the telescope. When a telescope is collimated, it is collimated at every position of the focuser (assuming the focuser is properly installed and is on-axis).

Collimation with a star is usually done near focus (just inside or just outside focus), using the symmetry of the Airy disc as a guide.

- Warren

Salad's referring to some image shift he noted on the Crayford. His previous post described a variability of the collimation when he changed the focuser position. Now that he has seen it again on the Synta focuser I'm thinking that the orientation of the focuser tube is the source of all his problems. It may be that the focuser is not 'normal' to the plane of incoming light and is actually cocked at an angle...

It could be that the OTA is out of round from being dropped on the Synta focuser during shipment. It is aiming at a point slightly different than the position of the secondary.
 
Last edited:
  • #35
russ_watters said:
I guess I missed the part about changing-out the focuser. There are several things that can go wrong there and a good rule of thumb for any new device you buy (whether it be your car, your computer, etc.) is to get it working stock before trying to modify it.

AMEN to that!

Chroot, I replaced the stocky and got that blessed chimney into focus! One variable eliminated!

Now...they accidently sent me two Crayford upgrades. i am going to try the other one now and see what happens.

Casey
 
  • #36
Even if the focuser was not normal the optical axis, it would still be able to reach focus -- or, at least, some small part of the image would be in focus. Futhermore, he claims he can reach tolerable focus with one eyepice but not with another.

- Warren
 
  • #37
Saladsamurai said:
Now...they accidently sent me two Crayford upgrades. i am going to try the other one now and see what happens.

There's so much going on here that you didn't tell us from the beginning Saladsamurai... it would have been so much easier for us to help you had you given us all the information from the beginning...

Anyway, you need to measure the distance between the top of the eyepiece and the OTA when each eyepiece is in focus. Any focuser replacement that is appropriate for your telescope needs to be able to put the eyepieces into those same exact positions.

By the way, are you using 1.25" or 2" eyepieces? Is your Crayford focuser a 2" focuser? Are you using an adapter to put a 1.25" eyepiece in it? Are you using the adapter properly?

- Warren
 
  • #38
chroot said:
There's so much going on here that you didn't tell us from the beginning Saladsamurai... it would have been so much easier for us to help you had you given us all the information from the beginning...

Anyway, you need to measure the distance between the top of the eyepiece and the OTA when each eyepiece is in focus. Any focuser replacement that is appropriate for your telescope needs to be able to put the eyepieces into those same exact positions.

By the way, are you using 1.25" or 2" eyepieces? Is your Crayford focuser a 2" focuser? Are you using an adapter to put a 1.25" eyepiece in it? Are you using the adapter properly?

- Warren

Chroot, see post #1, step 2.

Or is it the "two" focusers that you are referring to? Because by that I meant that whoever boxed up the scope obviously lost track and put an extra upgrade in the box holding all of the parts.

Also; 2"Crayford 1.25" eyepieces...using 2---->1.25 adapter

Casey
 
  • #39
Are the two focusers the same? If not, how are they different?

- Warren
 
  • #40
chroot said:
Are the two focusers the same? If not, how are they different?

- Warren

The two New ones (the Crayford upgrades) seem identical. I installed the other upgrade (this makes both that I have tried) and I get the same poor results.

Since the two Crayfords yield the same result I will assume they are
identical. Thus, for simplicity's sake I will refer to my focusers as the Crayford and the stock (we'll pretend I don't have an extra one).

Now the stock appears to be in working order. However, when I install the Cayford, I cannot get things into focus at HIGH power. The focuser does not seem to be high enough.

That is, at its max extension it is about to come into focus; i.e. If I could extend it more, I would be in good shape.

Would does this require of me? Shimming?

Thanks guys,
Casey
 
  • #41
Have you measured the distances between the eyepieces and the OTA at focus? Is the focuser not capable of this amount of travel?

If I were you, I'd just not use that focuser. Perhaps you really did get the wrong one. Can you call Orion and ask? Can you post the model numbers of the scope and focuser?

- Warren
 
  • #42
I got it. The distance was off. I found another adapter type thing in the other box with the extra focuser.

I placed both the stock and Crayford next to each other and fully extended their tubes. The stock sat a scoach higher then the Crayford. So I took some stuff apart and unscrewed some others and found the culprit.

I am waiting for dark to find out if the spider vanes are an issue, but I have new ones coming.

Thanks for all the help,
Casey
 
  • #43
Okay... if the spider vanes aren't an issue in the daytime, they won't be an issue at night. Just make sure you put the scope into proper focus. You may wish to start by focusing on something "easy" like the Moon, rather than trying to focus on stars. A surprising number of new amateur astronomers have problems focusing on stars, mistaking reflections and other light -- even when completely out of focus -- for stars in the eyepiece.

Now that you roughly know the positions at which both eyepieces reach focus for a distant terrestrial object, you'll know where to begin trying to find focus at night.

- Warren
 
  • #44
chroot said:
Okay... if the spider vanes aren't an issue in the daytime, they won't be an issue at night

- Warren
That's good news. I have the finder aligned. And I have used a telescope like this before (only much smaller). This focusing/spider issue was the only problem.

Thanks for all the help,
Casey
 
  • #45
Awesome.
 
  • #46
Saladsamurai said:
Awesome.

I take it the scope worked at night?

- Warren
 
  • #47
chroot said:
I take it the scope worked at night?

- Warren

Indeed. Thanks again for the help. If you had not suggested comparing the focusers, I would not have noticed that something was missing.

It may be common knowledge to anyone who knows anything about optics, but it had not occurred to me to check the lengthds of the focal tubes fully extended.

Casey
 
  • #48
Saladsamurai said:
Indeed. Thanks again for the help. If you had not suggested comparing the focusers, I would not have noticed that something was missing.

It may be common knowledge to anyone who knows anything about optics, but it had not occurred to me to check the lengthds of the focal tubes fully extended.

Casey
Aha! It appears that you may need a (cheap) extension tube to achieve adequate back-focus with that Crayford-style focuser. That will let you take advantage of the "regular" and "fine" focusing adjustments of the better unit. You may be able to clamp the set-screws on your eyepiece adaptor with the eyepiece withdrawn part-way to get the same effect, but it's nice to get the proper accessory and make stuff work like it's supposed to.
 
  • #49
This thing definitely works pretty sweet now.

I would like to invest in some sort of filter to aid in looking for nebula and what have you. Something that will help with the light pollution. Any suggestions?
 
  • #50
Well, light pollution filters and "nebula filters" are two different animals. The typical "nebula filter" is an Oxygen-III filter, but they're expensive and only work on certain nebulae. They also block light of all other frequencies; stars become dim spots. Unless you know exactly where to look, these filters can actually do more harm than good, since you won't be able to star-hop.

You might want to start with a wide-band light pollution filter and just see how you like it. Don't go for a narrow-band filter, because they'll cause you the same problems with star-hopping. Don't expect miracles, but for $50 or so they can be a good tool to have in your eyepiece box.

All that said, you will probably find that the two most useful accessories will be: 1) a Telrad finder and 2) a couple of nice, high quality, versatile eyepieces, e.g. a TeleVue Zoom.

- Warren
 

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