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Hair/scratch on primary mirror. Is it a scratch or a hair. My anxiety isn't taking it well.


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image.thumb.png.7663b692d4a9eaeff4265aa6d12d99d9.pngBought my newtonian reflector a few days ago. First scope. Below the primary mirror seems to be a hair/ scratch just below the primary mirror. I am anxious it is a scratch and want to know if it'll effect viewing. Its visible in varieties of light. 

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Will keep it in mind, just love my things to be in tiptop shape. Convinced it’s not a scratch because of its weird pattern. Almost looks like a toddler drew a very wobbly “x” on the mirror. Pretty sure it’s just a seed. 

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Almost certainly a hair - it's very plausible that a hair fell in, but very difficult to imagine how it could get scratched. 

But in many ways it doesn't matter - it won't affect views, and few people keep their Newt's long enough to need to clean the mirror (which isn't to say people don't clean them - just that it's rarely necessary!)

 

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As already mentioned, whether it’s a scratch or a hair it won’t have a bad effect on the view.  All optical surfaces tend to look dreadful under bright torchlight.

Best advice- don’t shine bright lights at your mirror😁

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Next advice - don't clean the mirror.
Every time you clean a mirror there is risk of adding scratches and other problems. They have to be really really grotty before the view is affected.

If you spill a full cup of tea on a mirror. If it gets covered in pollen and tree sap to the point of becoming foggy. If it gets bird droppings on there.
That is the time to clean.
Even then. It may be that water, a drop of detergent and a rinse will sort it. No touching required.

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Thank you all for the replies! Very helpful, pretty sure it’s just one of those seeds that likes to fly around. Was just a little concerned because I know pollen can really damage a mirror if left there for a long period of time. Completely of topic here: how do I locate sombrero galaxy and will I be able to see it with an 8inch Dob in bortle 5/6 skies? I got very close to locating it yesterday but just couldn’t pinpoint it disappointingly. Any tips from observers that have managed to locate it before?

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11 hours ago, Daniel_J said:

Thank you all for the replies! Very helpful, pretty sure it’s just one of those seeds that likes to fly around. Was just a little concerned because I know pollen can really damage a mirror if left there for a long period of time. Completely of topic here: how do I locate sombrero galaxy and will I be able to see it with an 8inch Dob in bortle 5/6 skies? I got very close to locating it yesterday but just couldn’t pinpoint it disappointingly. Any tips from observers that have managed to locate it before?

Rest assured, my 200P mirror looks terrible if I shine a light down there. The only thing I've cleaned is my Skymax 127 meniscus, but that was particularly bad. The saying goes "look through your optics, not at your optics".

The sombrero may be visible B5/6 with an 8" dob, I know it is from Bortle 4. Start by finding the constellation Corvus. It sits underneath the bowl of Virgo. You should be able to make out Algorab at the top of Corvus. What I then do is find the star HD110317J, a couple degrees north of Algorab. Under B4 skies this is faintly visible naked eye so I point my finder at it, under B5/6 I'm not sure if it's visible naked eye, but a little scanning and patience with the finder should do the trick. From there I nudge a little in the direction of Porrima and I'm looking for a formation of 3 stars close together - these are a useful pointer for the Sombrero! I should mention I start with a lower powered eyepiece for the widest field of view. A dob oriented view should show the 3 stars to the left of your image, and the fuzzy sombrero should be visible towards centre. Patience and practice is all it takes, but trust me it is worth it - seeing that bulging core and dust lane with your own eyes is incredible! With my 200P, I find a 20mm EP at 60x gives the best view. 

Screenshot_20220502-075121.thumb.jpg.2f6c1253232b3df4ef4ea46b91bdbcf5.jpg

Screenshot_20220502-075131.thumb.jpg.17d0d5e46f518d6f3d1e92909ec3d9aa.jpg

Star hopping is a bit of a skill, but I only bought my 200P 3 months back and soon got the hang of it. Use Stellarium or similar to find the bright stars or objects of significance near, or on your way to, your target. 

Edited by OK Apricot
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7 hours ago, OK Apricot said:

Rest assured, my 200P mirror looks terrible if I shine a light down there. The only thing I've cleaned is my Skymax 127 meniscus, but that was particularly bad. The saying goes "look through your optics, not at your optics".

The sombrero may be visible B5/6 with an 8" dob, I know it is from Bortle 4. Start by finding the constellation Corvus. It sits underneath the bowl of Virgo. You should be able to make out Algorab at the top of Corvus. What I then do is find the star HD110317J, a couple degrees north of Algorab. Under B4 skies this is faintly visible naked eye so I point my finder at it, under B5/6 I'm not sure if it's visible naked eye, but a little scanning and patience with the finder should do the trick. From there I nudge a little in the direction of Porrima and I'm looking for a formation of 3 stars close together - these are a useful pointer for the Sombrero! I should mention I start with a lower powered eyepiece for the widest field of view. A dob oriented view should show the 3 stars to the left of your image, and the fuzzy sombrero should be visible towards centre. Patience and practice is all it takes, but trust me it is worth it - seeing that bulging core and dust lane with your own eyes is incredible! With my 200P, I find a 20mm EP at 60x gives the best view. 

Screenshot_20220502-075121.thumb.jpg.2f6c1253232b3df4ef4ea46b91bdbcf5.jpg

Screenshot_20220502-075131.thumb.jpg.17d0d5e46f518d6f3d1e92909ec3d9aa.jpg

Star hopping is a bit of a skill, but I only bought my 200P 3 months back and soon got the hang of it. Use Stellarium or similar to find the bright stars or objects of significance near, or on your way to, your target. 

Thank you so much! They are some very helpful diagrams. Looking at them, I was very very close to finding it. I think what threw me off was the fact that the image through my finder scope is inverted so I was moving the scope the wrong way. I’ll have another go when the skies clear up here. I can’t wait to find it! Sombero galaxy is definitely up there with one of my favourites, a long with the whirlpool galaxy that is very good for viewing right now here in the UK.

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7 hours ago, OK Apricot said:

Rest assured, my 200P mirror looks terrible if I shine a light down there. The only thing I've cleaned is my Skymax 127 meniscus, but that was particularly bad. The saying goes "look through your optics, not at your optics".

The sombrero may be visible B5/6 with an 8" dob, I know it is from Bortle 4. Start by finding the constellation Corvus. It sits underneath the bowl of Virgo. You should be able to make out Algorab at the top of Corvus. What I then do is find the star HD110317J, a couple degrees north of Algorab. Under B4 skies this is faintly visible naked eye so I point my finder at it, under B5/6 I'm not sure if it's visible naked eye, but a little scanning and patience with the finder should do the trick. From there I nudge a little in the direction of Porrima and I'm looking for a formation of 3 stars close together - these are a useful pointer for the Sombrero! I should mention I start with a lower powered eyepiece for the widest field of view. A dob oriented view should show the 3 stars to the left of your image, and the fuzzy sombrero should be visible towards centre. Patience and practice is all it takes, but trust me it is worth it - seeing that bulging core and dust lane with your own eyes is incredible! With my 200P, I find a 20mm EP at 60x gives the best view. 

Screenshot_20220502-075121.thumb.jpg.2f6c1253232b3df4ef4ea46b91bdbcf5.jpg

Screenshot_20220502-075131.thumb.jpg.17d0d5e46f518d6f3d1e92909ec3d9aa.jpg

Star hopping is a bit of a skill, but I only bought my 200P 3 months back and soon got the hang of it. Use Stellarium or similar to find the bright stars or objects of significance near, or on your way to, your target. 

This is where I was when looking through my telescope, I will definitely try again when the sky clears up now that I have a better understanding. Thank you!

652BB18D-539C-41E6-94CF-652678347866.jpeg

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