Collimation needed?

[Damien2904]

Hello everyone.

Over the last week or so, I've started to think that my telescope may need collimating / mirrors realigning, as objects don't seem to focus all that great. I've never made any adjustments since having the telescope, however I imagine due to movement about the house/garden the mirrors may have moved slightly. Also from what I'm reading online about what I should be seeing I don't seem to be achieving this, with Jupiter I can just about make out some of the cloud bands, but never much detail & never the Red Spot (I do understand it does depend on atmospheric conditions). 

My telescope is a Celestron Powerseeker 127EQ, Newtonian reflector, Bird-Jones.

I've posted some photos below & would appreciate your opinion on whether you think its necessary.

The first three photos are aimed at Arcturus, with the eyepiece slightly out of focus to create the ring effect, the black circle does look slightly off centre to me. 🤔

The next couple are looking through the focuser without an eyepiece. The reflection of my phone again looks off centre, more towards the upper left side. 

 

Any feedback would be appreciated before I head to YouTube to work out how to adjust it. 

Damien

[Moonshane]

I have never used or collimated one but the link below might help. Re Jupiter, the GRS reveolves with the plant so you need to look at the right time.

This link is useful for establishing when the times will be. On average it's about every 10 hours. Planetary observing needs long periods of observing and concentration with conditions being the key factor affecting what you see. I always found magnification of about 100-150x yields the best results most often. It's surprising what can be seen on a small disk.

https://skyandtelescope.org/observing/interactive-sky-watching-tools/transit-times-of-jupiters-great-red-spot/