How to clean corrector plate, diagonal mirror, eyepieces etc?

[Sedna]

Hi all, my equipment is getting a little dirty and I'd like to clean those pieces which I can clean myself without a professional. I own a Celestron 8SE and I have some dust/dirty in my diagonal mirror. Would also like to clean the corrector plate and eyepieces. Is there a guide someone on here can recommend to me? Any tips/suggestions? Thanks!

[Demonperformer]

3 hours ago, Sedna said:

Any tips/suggestions?

Put it off as long as possible ... a "dirty" surface will do better than a badly cleaned one, particularly with the risk of damage to coatings.

Some advice here and lots of youtube videos (search: cleaning sct corrector plate)

[Carbon Brush]

Fully agree with the above post.

Optics have to be really really dirty before you consider dismantling for cleaning.
The loss of image quality is minimal even with really mucky mirrors and lenses.

Deposits on outer faces of lenses can be easily cleaned. I use Baader Wonder fluid. I know it sounds like a well marketed kitchen surface cleaner. It is an excellent lens cleaner.
FLO sell a package of fluid and good quality lens cloth.  Some consider it expensive and have their own recipes. But compared to a scrap scope? A 100mL bottle lasts ages.

Mirrors are a different matter. They are best untouched if possible. Nothing more than agaitated liquid.

If the marks are fungus rather than dirt, they need to be addressed as they will slowly grow and wreck coatings.
But there is no need to rush out today and do something today. It is slow growing. Take advice and consider professional cleaning.

Hope this helpsw, David.

 

[Sedna]

6 hours ago, Carbon Brush said:

Fully agree with the above post.

Optics have to be really really dirty before you consider dismantling for cleaning.
The loss of image quality is minimal even with really mucky mirrors and lenses.

Deposits on outer faces of lenses can be easily cleaned. I use Baader Wonder fluid. I know it sounds like a well marketed kitchen surface cleaner. It is an excellent lens cleaner.
FLO sell a package of fluid and good quality lens cloth.  Some consider it expensive and have their own recipes. But compared to a scrap scope? A 100mL bottle lasts ages.

Mirrors are a different matter. They are best untouched if possible. Nothing more than agaitated liquid.

If the marks are fungus rather than dirt, they need to be addressed as they will slowly grow and wreck coatings.
But there is no need to rush out today and do something today. It is slow growing. Take advice and consider professional cleaning.

Hope this helpsw, David.

 

Thanks David, got it, I won't try to clean my SCT optics yet. But for my eyepieces, there are some bits of dust that look like they would come off easily. Would you recommend one of those cans that spray air, the ones people use to clean keyboard (like this one)? In particular, my diagonal mirror has a lot of dust, could this help?

[Carbon Brush]

Glass lenses. That is eypieces and 'the front bit' on a refractor or compound scope have good coatings that will withstand mild chemical cleaning and abrasion. Like Baader Wonder fluid and the cloth.

As a comparison on lens cleaning, I know that spectacle lens coatings fragment and peel after multiple cleaning operations with neat isopropanol. Which is a fairly mild solvent that is used in many cleaning applications.

The canned air products are a bit of a risk. Some are clean and dry gas. With a pure propellant. Others are not so good. It depends on the manufacturer.
If particles are so small they don't block the nozzle, does that pass the quality test?
If the gas and propellant don't contain too many oil droplets from the compressor used to charge the canisters, that is OK.

Before spraying canned air at a (soft) mirror coating or lens I would refer to the manufacturers data on product purity. NOT the sellers data.
If you can't get the information from source, look for something else.
Products for sale in the EU from reputable distributors have the manufacturers safety data sheet available and sometimes a purity statement.

Examples of products from just one UK supplier are in this link.

https://www.rapidonline.com/air-dusters

You will see that product data and safety information is included.
Though a quick glance did nothing to assure me there was not going to be oil spray or grit blasting.

On your diagonal, I would be very tempted to ignore the problem. If it really is a problem then squirt with Baader fluid.
When it dribbles off, it won't harm painted or finsh on the diagonal metalwork or plastic.

Hope this helps, David.