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Secondary Mirror in frame when viewing Mars?

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Sorry if I’ve made a stupid beginners mistake but can anyone help with the following?

I’ve bought myself my first telescope, a Skywatcher Heritage 150P flextube and tonight was the first clear night to have my first views.

I checked the collimation before hand and it was fine. I live outside Newcastle in a small village and it seem pretty dark in our back garden.

I started with the moon which was crisp and clear with good definition of craters.

I then moved to Mars which was easy to find but when I tried to focus I got a red disc but with the secondary mirror shadow (circle in the centre with 3 sticks to the sides) over it.

Obviously I’m doing something wrong so can anyone give me some advice?

Thank you.


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Hi, I wasn’t using a Barlow but now I think about it the frame appeared when Mars was very large in the viewer.

Probably my expectations of how big it should be we’re unrealistic 🙂

Thanks for the quick answer, I’ve been really impressed how welcoming this forum is.


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An object at focus through a scope appears at it's smallest when it is at sharp focus. Mars will look very small currently. Just a tiny pink disk like this:


If you can see the dark shape of the secondary mirror and it's supports against a larger disk of light, you are way out of focus.


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