Spider vein in image

[Ged k]

Hi all , new to astronomy I just bought my first telescope , omegon 150/750 eq3 , viewed the moon and work perfect , tried mars last night and located and centred in image , as I tried to focus the image just turns to spider vein , basic question but do I need to just change magnification to see mars as a sphere or do I have an issue with telescope , is it normal for vein to appear while focusing image 

[alacant]

Hi

ATM, Mars won't appear much different from a star at magnifications available with your 150. You should though be able to discern a small disc with a short eyepiece if the atmosphere is steady.

Either side of focus, you will see the spider vanes -with a black blob in the centre- as you describe. Focus on, say Capella as tight as you can. Then leave that focus position for Mars. That represents the best you'll get.

Cheers and HTH

[Ged k]

Cheers bud ill give that a go tonight if get clear skies 

 

[vlaiv]

Not sure what you mean by spider vane, but if it looks like this:

only red in color - than that is perfectly fine.

Newtonian scopes show diffraction spikes on all bright point like objects. Mars is probably too small at the magnification that you are using and it looks almost star like so you are not seeing disk of it.

If you turn your scope to any bright star and focus it - it will look like above image (except for color - different stars will have different colors, this one is blue) - again, this is normal for newtonian scope and shows only on bright objects.

It won't show on mars when the planet is larger and you use more magnification (it will show - but it will much fainter and it won't bother you at all).