Help Spider web on my sct correcting plate

[Jeremy Parker]

After a glorious viewing last night, I had a close look at my Meade 8"sct and found what look like some spider threads on the outside of the corrector plate next to the perimeter of the secondary mirror.
It is not a lot and consists of a few threads that I tried to remove using an air blower but to no avail! It seem to be truly stuck to the glass plate.
I am a bit reluctant to use a cotton bud or any implement that will make physical contact, as it might smear the glass and make it worse.
Anyone has any experience cleaning their sct corrector plate?
I know there are plenty of advice on the Internet on how to do it or not to do it but I would like to hear from you people who has actually done it as to whether it is worth doing it?

Cheers!

[casstony]

Hi Jeremy, providing you are very gentle there's no problem with touching the corrector plate to lift the spider web off. To avoid the possibility of scratching, wet the Q-Tip to provide lubrication and rotate it in one spot (with no pressure) to lift the web off. Use multiple Q-Tips until you've got all of the web off - you could try using water or isopropyl alcohol to see what works best. Residue from the solvents is no problem - better to have cleaning marks than to leave other organic substances sitting on the corrector that might damage the coatings over time.

[GeoffW1]

Hi,

Agreed, just treat it gently the same as a lens glass - which it is.

Cheers

[dannat]

Spider web should come off easily, u sure it's not fungus:shrug:

As for cleaning I like things to be quite moist, not dry-windex is good as its streak free, if it's fungus I would be hitting it with acetone (though be careful with this as you don't want it getting to the edge of the corrector pate, be careful to keep it on the glass

I do have a box of zeiss cleaning wipes on the way but they won't be here till next week, I bought 200 so can spare you one

[gb_astro]

If you do try it Jeremy, be prepared to clean the entire corrector plate.
Unless your scope is pretty brand new, once you start putting liquids on the plate, you might find that the fine even layer of stuff that is on most SCT's becomes disturbed leaving random patterns and smudges showing where you have cleaned locally.

gb.