getting rid of condensation

[ian_j_kirk]

Hi everyone,

Just been outside having a quick viewing session for an hour or so. As you all probabley know, its freezing outside, so my scope also got very cold. When i brought it in to the warmer house, condensation built up. After all the condensation has evaporated/dried out, if the condensation was on one of the mirrors, is there a chance that it could leave a mark on the mirrors? A bit like on the inside of your car windscreen?

Thanks

Ian

[Velvet]

dont know bout that, but we all have the same problem and i just let mine dry naturall and dont seem to have any probs. I have a news and a frac so i think you will OK

Regards

Velvet

[Antscope]

depends whats floating around in the air at the time it condensed on your mirror, but I wouldn't worry about it, you can minimize condensation by placing a shower cap on the open end of the scope before you bring it in, that way it will come up to ambient temperature in a controlled way, plus less condensation.

[ian_j_kirk]

Thanks guys! That was such a quick response too! That has put my mind at ease. Was worried i had stuffed the primary mirror or something

Ian

[Antscope]

primary mirrors are usually over coated with quartz after they have been "aluminized", quartz is pretty tough stuff so its impervious to atmospheric pollutants etc

[jimmyjamjoejoe]

At worst you'l slowly get some dust building up and leaving water marks. It'l take years, if not decades to build up enough to affect views.

If you're really worried about it, rinse the mirror with distilled water once in a while.

[brantuk]

When I bring a newt indoors from the cold - I point it slightly down from horizontal while it dries out so any condenstaion formed drips downwards away from the mirror. I just pop an old towel on the floor to catch any drips from the tube opening.

[cantharis]

If your observing session is over, no way you can´t keep all condensation at bay with some mega heat from the wife´s hairdryer - my FAVOURITE astronomy accessory.

[Moonshane]

you cannot observe inside and if you bring the scope inside after observing (when it's cold at least) you cannot avoid condensation. it's not harmful generally as long as it can escape the tube - it's when you keep the condensation hidden away (e.g. it may form on the mirror if kept in a garage and you might not notice it) that it causes issues.

it's normal and nothing to worry about as suggested above. my 16" mirror has a couple of water drop marks and plenty of dust and it's not an issue. I don't generally clean my mirrors but you can do safely if needs be using tried and tested methods - don't just go ahead and clean it - check out the process first. on the whole though it's not worth doing.

[scarp15]

After a session, I always bring my scope inside to an unheated room (by which time the entire house is unheated anyhow). For the C8 i point it down slightly and remove the dust lid for a short period, as it is the corrector plate that collects the condensation. I also do the same with my eyepieces. The following morning I just use an air blower before putting everything away.

[LukeSkywatcher]

you cannot observe inside

I beg to differ. You can observe from inside (granted not a s well as you can from outside), but you have to have to make sure you do two things first.

1/ Make sure the heating is turned off in the room where you will be observing from

2/ If possible (without having a family mutiny on your hands) make sure the window in the room you are observing from is open wide so that the room can cool down to outside temperature.

I have found through experience that when observing through double/treble glazed windows that the only thing that doesnt work is observing planets. You end up seeing 3 ghost images in RGB and the planet itself will just be a white blob with no features. Stars,clusters,nebs,meteors,galaxies are all still very visible through windows.

I'm not suggesting everyone do it. There is no substitute for being outside. However for people with mobility issues, it is a solution.

Oh yeah...............one more thing................floor boards tend to be not very level or secure so they do tend to make the scope wobble a bit and cause vibrations. All depends on how old your house is though.

[Moonshane]

fair point Paul - not the best but if you have no option - I agree.

[LukeSkywatcher]

fair point Paul - not the best but if you have no option - I agree.

Where there is a will, there is a way.