Celestron C9.25 cleaning the mirror?

[TerryW]

Anyone have any experience of disassembling and reassembling the C925?

After keeping my scope outside for a month and removing the build up of moisture using non-intrusive means I am now left with a cloudy (no pun intended) film on the mirror as viewed under strong light through the objective lens.

Thanks in advance.

Terry

[faulksy]

i take it that its on the inside ? if its the outside badder optic cleaner is very good with there cloth

[TerryW]

Martin from First Light Optics just straightened me out. The clouding effect is caused by the coatings.

I had convinced myself that in causing the scope to get condensation inside it I had fogged up the mirror with something horrible.

It looks to have completely survived the condensation which I have successfully removed using a computer fan in reverse and a gentle warming from a fan heater. Took all night for the condensation to fade away.

Terry

[faulksy]

i made like a fake ep out of nylon in work bored out the ctr and made a cap to close the end off, i then fill the chamber with bags of silica gel wich obsorbs all the moisture inside the ota not that i get any now due to this mod. you could probably use an old ep just remove the glass

[TerryW]

Good one.

I have a load of tiny (1" x 1") bags of silica gel. I'll see what I can rustle up.

I'd like to keep the OTA outside on the mount. As the OTA is quite heavy and the losmandy fitting is so flaming awkward to engage that I tend to disturb the mount's north alignment when I screw the OTA on. The whole idea of leaving the mount outside is that I don't need to grovel on the wet shingle to align it every time I use it.

I think a few soft rubber sealing rings of the correct size might help the situation. Plus, Martin at FLO suggested using a celestron focal reducer as it seals the scope better. I am trying to avoid spending any more money on the scope just now but I may end up investing a few pence on rubber seals if I am brave enough to leave it outside again.

Terry