Dirt on the inside of my refractor

[riogrande100]

I have what appears to be some dirt on the inside of my orion 80, is their a way to clean the inside of the lens? The outside is easy as one can easily apply the correct solution to it, but on the inside i don't know how to.

[GazOC]

I think the lens cell just unscrews, thats certainly the case on the 100mm/120mm models.

[riogrande100]

cool will give it a try tonight when i get home.

[crepitis]

I dont have an Orion refractor, but on my TAL 100RS the lens cell is held in place with three screws and could be easily removed if required, if your Orion 80 is the same as the larger ones as GazOC suggests, then it should be fairly easy..good luck.

[tooth_dr]

If its the same as a SW ED80, it just screws off.

[riogrande100]

Disaster!!!!!!

II bought the scope second hand anyway when looking at the lens, it just seemed to either have a lot of slight scratches, or extremley dirty. used a lint free cloth and some water and kept at it, but it still didn't come crystal clear!

when putting the lens back in the cell, i made a bit of an error. The lens became stuck in trying to pry it out i chipped a bit of the lens!!!

However aftre putting it all back together again the lens looks cleaner and the cip is so far on the edge that it is not seen at all!!!

However the fact that is slightly chipped pains me, but the fact the lens still contains some slight smudges, and doesn't look crystal clear annoys me.

I should have bought a new scope, i guess not all astronomers look after their kit

[GazOC]

Sorry to hear of the problems, try and not let it affect your enjoyment of the scope. The slight smudges (while a pain) won't impact the views you get.

[riogrande100]

I have taken some really nice pictures with this scope for nice widefield DSO objects (Pleides and M42). The optics are far superior to my celestron 102mm wide view achromat. So it isn't all bad, the main reason i knew the cell was dirty was when configuring my off-axis gudier and the guide cam kept picking up the dirt on the lens.

[Antocharis]

Dear All,

I have a TAL 100RS refractor, and I made a mistake. I poured a lot of alcohol on it while cleaning, and the fluid flowed inside of the lens elements. I'm aware of the risks of miscollimation, but I have to disassemble the lens. The problem is, the lens doesn't move from the lens cell. Can anybody help me how to disassemble the lens?

[steelfixer]

Rio I recon that you have all but destroyed that scope.

I think you should buy another one and seeing how its Christmas I'll take it off your hands for safe keeping I will even throw in the cost of the P&P. lol

[nightfisher]

Dear All,

I have a TAL 100RS refractor, and I made a mistake. I poured a lot of alcohol on it while cleaning, and the fluid flowed inside of the lens elements. I'm aware of the risks of miscollimation, but I have to disassemble the lens. The problem is, the lens doesn't move from the lens cell. Can anybody help me how to disassemble the lens?

Here goes: remove the lens cell from the tube (3 screws) i would then place a strip of tape along the cell and a small bit on each lens so they all line up, giving you a reference point for re assembly, on the inside of the lens cell should be a ring that unscrews to release the 2 glass elements, release this, lift out the first lens, clean CAREFULLY with a micro fibre cloth, then second lens, then refit so all three bits of tape are lined up

[Peter Drew]

riogrande100.

Are you sure your original problem was dirt on the objective lens?, in a later post you suggest that your guidecam picked this up. Generally speaking spots shown by a camera are usually caused by dirt on the sensor.