<p>I have been collimating my newly bought first Newtonian telescope for a few days now, but I can't get the center of the circles to align with the intersection point of the spider's reflection. I have drawn a simple picture that illustrates what I see:</p>
<p><a href="https://i.ibb.co/XzV8gC4/20210415-002956.jpg" rel="nofollow noreferrer"><img src="https://i.ibb.co/XzV8gC4/20210415-002956.jpg" alt="enter image description here" /></a></p>
<p>My question is, which mirror do I need to adjust, and in which way, in order to get the cross to align with the circles in the correct way.</p>
<p>Thanks in advance.</p>
<p>Edit:
If this is something that is not supposed to happen, then please tell me so that I would contact the seller. Thanks again.</p>

CC BY-SA 4.0
2021-04-14T16:09:59.633Z
Spider reflection looks uncentered. That'd happen if main mirror is tilted.
Wayfaring Stranger
CC BY-SA 4.0
2021-04-14T16:45:48.967Z
The location of the spider does not matter. You want all of the optics aligned. Are the optics aligned? Is the spider a different design or is the spider physically centered in the tube?
JohnHoltz
CC BY-SA 4.0
2021-04-14T23:12:42.117Z
@WayfaringStranger
Which mirror of the two?
Ramy Gaw
CC BY-SA 4.0
2021-04-14T23:14:17.370Z
@JohnHoltz
By all optics do you mean the circles?
Ramy Gaw
CC BY-SA 4.0
2021-04-15T00:57:15.633Z
@RamyGaw The main, big, mirror.
Wayfaring Stranger
CC BY-SA 4.0
2022-08-13T06:34:21.307Z
The image is not visible to me
Nilay Ghosh
<telescope><collimation>
What to do in case of concentric circles that are not aligned with the cross after collimation (Picture inside)?
Ramy Gaw
# What to do in case of concentric circles that are not aligned with the cross after collimation (Picture inside)?

(Asked by: username_0 on 2021-04-14)

I have been collimating my newly bought first Newtonian telescope for a few days now, but I can't get the center of the circles to align with the intersection point of the spider's reflection. I have drawn a simple picture that illustrates what I see:

[![enter image description here](https://i.ibb.co/XzV8gC4/20210415-002956.jpg)](https://i.ibb.co/XzV8gC4/20210415-002956.jpg)

My question is, which mirror do I need to adjust, and in which way, in order to get the cross to align with the circles in the correct way.

Thanks in advance.

Edit:
If this is something that is not supposed to happen, then please tell me so that I would contact the seller. Thanks again.

**Tags:** telescope, collimation
> **Comments:**
> **username_1**: Spider reflection looks uncentered. That'd happen if main mirror is tilted.  
> **username_2**: The location of the spider does not matter. You want all of the optics aligned. Are the optics aligned? Is the spider a different design or is the spider physically centered in the tube?  
> **username_0**: @WayfaringStranger Which mirror of the two?  
> **username_0**: @JohnHoltz By all optics do you mean the circles?  
> **username_1**: @RamyGaw The main, big, mirror.  
> **username_3**: The image is not visible to me  

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## 0 answers

