Why Is My Zhumell Dobsonian's Laser Collimator Missing the Secondary Mirror?

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The user is experiencing difficulty collimating their 12" Zhumell Dobsonian, specifically with the laser collimator missing the secondary mirror and hitting the wall instead. Initial observations suggest that the primary mirror is well-aligned, but the laser beam's misalignment indicates a potential issue with the secondary mirror. After adjusting the mirrors, the user found the laser beam centered on the primary mirror, yet the view through the eyepiece worsened. Ultimately, they concluded that further adjustments to the primary mirror were necessary, and after making those adjustments, they achieved the desired alignment. The discussion highlights the importance of careful mirror adjustments in achieving proper collimation.
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I have a 12" Zhumell Dobsonian and I've been trying all day to collimate it and can't get it lined up right.

This is what it looks like when peering into the eyepiece holder:
http://img184.imageshack.us/img184/4786/christmasscope008dx6.jpg

Can anyone tell me if this is a secondary mirror or primary mirror problem? I see all of the primary mirror and the spider is almost dead center, so it can't be that horribly misaligned, but when I put the laser collimator in the holder the beam completely misses the secondary mirror and hits the wall.

I'm really getting frustrated because it shouldn't be this hard. Can anyone help?

Thanks in advance.

EDIT: I used the laser collimator and adjusted the mirrors until the beam came back and hit the target area on the collimator and when I looked in the end of the tube (just for a second!) the beam was smack in the middle of the primary mirror, but now when looking through the eyepiece holder the image looks even worse than before. I don't really have anything around to focus on since it's nighttime and the scope is indoors, so I can't test it that way. But it seems to me that the image you see when looking in the holder should be close to perfect when the laser beam comes back and hits the target on the collimator.
 
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looks to me like you just need to adjust the primary mirror.
 
I tried collimating it with the laser and I think that was the problem. Now it's perfect, thanks!
 
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