I Am Cursed Ack Fi My New Telescope hates me

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In summary, Casey's telescope was not properly assembled and collimated, causing poor viewing conditions. He was able to see the spider vanes in the eyepiece when taking it out and looking at a distant object, but was not able to see them clearly when attempting to use the scope in the daytime. He was able to contact an astronomy club for in-person help.
  • #1
Saladsamurai
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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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  • #2
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
 
  • #3
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.
 
  • #4
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.
 
  • #5
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.
 
  • #6
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...
 
  • #7
  • #8
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?
 
  • #9
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
 
  • #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.
 
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  • #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
 

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