problems after home work with my telescope

Equipment Reflectors Troubleshooting
9 replies•506 views
marianobritogomez avatar
marianobritogomez avatar
Hello everyone. 
These last few days I have been trying to upgrade my sky watcher 150/750. I have flocked the inside of the tube, painted the sides of the primary and secondary mirrors, put an aperture ring on the primary mirror and trimmed the focuser tube 2 cm so it doesn't protrude. The problem I am having is that the stars now appear weird, as in the image I am showing you. I have collimated both mirrors with a laser collimator and they seem to be fine, however this problem has not been solved.
I hope that if any of you have had this problem you can tell me how to fix it.
Thank you very much.

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Björn Arnold avatar
Björn Arnold avatar
Hello everyone. 
These last few days I have been trying to upgrade my sky watcher 150/750. I have flocked the inside of the tube, painted the sides of the primary and secondary mirrors, put an aperture ring on the primary mirror and trimmed the focuser tube 2 cm so it doesn't protrude. The problem I am having is that the stars now appear weird, as in the image I am showing you. I have collimated both mirrors with a laser collimator and they seem to be fine, however this problem has not been solved.
I hope that if any of you have had this problem you can tell me how to fix it.
Thank you very much.

Looks to me as if you had pinched the primary mirror. Did you work on the mirror clips holding the primary mirror?

Björn
marianobritogomez avatar
marianobritogomez avatar
Yes I did Björn, to place this accessory in the primary mirror:
aperture ring
Björn Arnold avatar
Björn Arnold avatar
Yes I did Björn, to place this accessory in the primary mirror:
aperture ring

Then you should check that. The clips holding the primary shouldn't be too tight as this leads to deformation of the mirror.
marianobritogomez avatar
marianobritogomez avatar
Great. Thanks Björn Arnold for the quick help I'm going to fix this right now.
robonrome avatar
robonrome avatar
Make sure to let us know if this works too. Makes sense.
marianobritogomez avatar
marianobritogomez avatar
Hello everyone. The problem has been solved. Here is a picture taken last night.  It is always a pleasure to learn with all of you. Thanks for your help, The problem now is that an oval reflection has appeared around the star, also if you notice, the star is not even centered in the oval. If possible I would appreciate some advice.

Thank you very much 
marianobritogomez avatar
marianobritogomez avatar
Hi. I finally managed to solve the problem by adjusting the spider properly and releasing the secondary mirror screws a bit, which were quite tight. The image is now sharp and without that strange halo.
Thank you.
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Andy Wray avatar
Andy Wray avatar
@marianobritogomez   When you say you adjusted the spider, what exactly did you do?
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marianobritogomez avatar
marianobritogomez avatar
same distance on each leg of the spider @Andy Wray
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