Think my Telescope is out of Collimation need expert opinions

[StarDuke82]

Pretty sure my Scope is out of Collimation I first suspected when I never noticed any cloud banding observing Jupiter but I tried the old star test tonight using Venus and its actually bright enough to notice that the primary and secondary mirrors appear to be slightly off center,  (see I know how to adjust the mirror with the spidervane but I’m not sure which screws are the collimation screws on my Celestron the long or the short one’s flush with the base. The attached photos are through my eyepiece editing the contrast and shadows on one to better show the concentric rings and the spider vane, am I out of collimation like I suspect.

[fwm891]

You are but you really need to use a star to do a 'star' test. Venus shows phases (like the moon) and is an extended object telescopically so it will not show the ring patterns inside and outside of focus needed to fine tune collimation.

Polaris is a good target as it doesn't keep shifting from the FoV (though it is wide double star system!).

Edited March 1, 2023 by fwm891
Text added

[Peter Drew]

To me, it looks like the secondary shadow is reasonably centred on the spider vanes which suggests that the primary mirror needs adjusting to make the whole image central.    🙂

[StarDuke82]

Thank You both I read up on Collimation and made myself a Collimation Cap and did some adjustments today by aiming my scope at a sunny window and aligning the primary mirror point in the center of the the secondary as best as possible, and will have to wait until better weather this weekend to fine tune adjustments, may post an updated image of the results 

Edited March 1, 2023 by StarDuke82
Confused my primary and secondary mirrors

[Adam J]

On 01/03/2023 at 07:34, StarDuke82 said:

Pretty sure my Scope is out of Collimation I first suspected when I never noticed any cloud banding observing Jupiter but I tried the old star test tonight using Venus and its actually bright enough to notice that the primary and secondary mirrors appear to be slightly off center,  (see I know how to adjust the mirror with the spidervane but I’m not sure which screws are the collimation screws on my Celestron the long or the short one’s flush with the base. The attached photos are through my eyepiece editing the contrast and shadows on one to better show the concentric rings and the spider vane, am I out of collimation like I suspect.

Yes you are out of colimation although you wont get much finess on that looking at Venus you need to use a star really. Its important that the star is in the centre of the field BTW. 

 

Adam