What on earth is causing this...👀

[Ryan_86]

Hi guys, 

Following the collimation of my laser collimator this is the shap of the red dot exiting my quadruplet refractor. Notice towards the bottom it becomes pointed. I plan to fix a little focus tilt, if this doesn't resolve the problem i guess I'm stuck as it has no collimation screws for the lens

Has anybody seen anything similar? 

Many Thanks

Ryan

Edited December 12, 2023 by Ryan_86

[garryblueboy]

Looks like pinched optics 

[dweller25]

Is a star test the same ?

Edited January 8 by dweller25

[Peter Drew]

Could be a minor internal temperature plume effect.      🙂

[Ryan_86]

Thanks for your replies guys. Star tests showed perfect round stars when out of focus. This led me to look at the camera/oag/filter wheel end and it looks I'm on the right path as the oddly shaped stars rotate when I rotate the camera 90 degrees.