Optic cleaning

[obscura]

Having recently been embarrassed here by my "dirty" optics, can I open up a discussion on cleaning? To clear the "grime" I used a q tip and breath very gently on senser and eyepiece/barlows etc and blew odd dust off the diagonal and objective. That proved to be enough.

I am aware of the Baader Wonder fluid and cloth at £14ish. I do have from a previous experience with a Meade LX90 iso propyl alcohol and de-ionised water which I used in a 10:1 dilution. Is this mix OK for sensor, eyepieces and objective (but not diagonal of course). My gut feel is leave alone until necessary.

What methods are best recommended?

[rfdesigner]

Do nothing counts very highly.

When to clean?... how about take an image of a know constant intensity light source (moon comes to mind, but only at high altitude) measure the intensity you detect under controlled conditions (same camera/exposure etc., compare against your very first effort and when things have deteriated by say 10% then clean just the most obviously dirty part.

Derek

[obscura]

Sounds interesting but as you say, controlled matching criteria. But I'll give that a go.

Thanks for that.

[jgs001]

I'd go for a rocket blower and the wonder fluid. Although get a proper cleaning kit for the SLR. A q-tip is not normally recommended for sensors as it can leave behind bits. I normally only use the rocket blower on the objectives when they get dusty. If they get anything worse than dust, rocket blower first, then a gentle clean with the baader fluid. I use the same techniques with me camera lenses.

For the SLR sensor, I've cleaned mine a couple of times. The right kit makes it easy. The pads are the correct size for the sensor, and the formulation of the fluid needs to be correct. I was reading a case on a photography forum where someone had bought the wrong solution for his sensor, and no matter how many times they cleaned it, it didn't remove the dirt. Once they ID'ed that and invested in a bottle of the correct fluid, all the dirt was gone in a single clean. Sounds weird I know, but it worked.

[obscura]

Hi John.

I conceed and the 'wonder fluid' is on the list.