Marks on my primary :(

hurricane (Andrew) · #1 06-10-2010, 01:55 PM

Looking down the tube of my 12" dob, I've noticed the primary mirror had this kind of 'fog' on one half.

It looks like someone has breathed on it causing a fog, and compared to the clean/normal side it loses some clarity.
So today I decided to take out the cell, inspect a little more and give it a clean (help from the articles here), but the mark is still there.

The scope is only 8 months old. What is this 'fog' and is there anything apart from the processed described above that I can do to clean/remove it?

Thanks

icytailmark (Mark) · #2 06-10-2010, 02:11 PM

thats moisture on the mirror from dew. just get a hair dryer and blow down ur tube. give ur mirror a clean while u have it out of ur tube.I recently cleaned my 12" mirror. Fill up sink with a few drops of washing liquid and warm water. let the mirror sit in the water for 5 mins. shake the mirror around a little. Then get some cotten balls and lightly run the cotten over the surface of the mirror while its under water. Rinse off with distilled water and let it dry.

gts055 (Mark) · #3 06-10-2010, 02:14 PM

Hii, Its difficult to comment without seeing the mirror. Is the haze on the protective overcoated surface or on the aluminium coating under the overcoat? As cleaning has had no effect, perhaps best to see the mirror vendor. Is there a warranty period? Mark

hurricane (Andrew) · #4 06-10-2010, 04:20 PM

Thanks for your replies.

I don't believe it to be moisture as it was dry. I've also given it a wash and it is still there.

Is there a way to tell if its under or on top of the overcoat?
According to the website I bought it from it has a 'three-year factory backed genuine Australian warranty' - would that cover the mirror?

Paddy (Patrick) · #5 06-10-2010, 06:17 PM

Quote:

Originally Posted by hurricane

Thanks for your replies.

According to the website I bought it from it has a 'three-year factory backed genuine Australian warranty' - would that cover the mirror?

I would think so, Andrew. It is an essential element of the scope and I think they could only not cover it if it had been mistreated.

Most of the vendors seem good with after sales service, so I'd be contacting them and not doing anything more to the mirror to avoid any suggestion of voiding the warranty.

torana68 (Roger) · #6 10-10-2010, 11:54 AM

...make sure you let us know how well your treated with the claim.

hurricane (Andrew) · #7 18-11-2010, 11:43 AM

Hi guys, just an update.

Took it back to AndrewsCom and they were more than helpful.

I'm in Canberra, so I called them to see if I could take it in, and when I did they said they would replace it.

Less than a week later the new one was ready to pick up (so on my way to Sydney I dropped in), but there was a mistake with the size, so they sent down the correct one the next day - free of charge.

Very pleased and happy with their service.
The mirror is so shiny!

Jeeps (Sam) · #8 18-11-2010, 12:19 PM

Andrews are always great to deal with. Good to hear you've got it sorted out!

cheers

Steffen · #9 18-11-2010, 03:24 PM

That's great news, and good to hear you got decent service from AndrewsCom. I've got a Dob from them as well.

That said, the rubber clamps holding the mirror look awfully tight in your pictures. Did you not see any pinching in your star images? Normally, you should just be able to put a business card between mirror and clamp, your clamps seem to be bending under tension?

Cheers
Steffen.