Cleaning the inside objective lens of a refractor

[hotspur]

I recently did some tidying up in my observatory,and had a look down the scope to see if the objective lens was clean,the front was good,but I noticed some very small things on the inside side of the lens,possibly mould.What is the procedure to clean this side of the lens?I have heard people talk about this issue-not sure what the conclusions were-do people send the tube away to the manufacturer?or somewhere that specialises in taking them apart?or do others do this job themselves?The offending stuff is very small and does not affect seeing of photography.Interested to here what others do-as it sounds like this issue-will affect/has affected many before.Thanks.

Chris

[dannat]

Chris r u talking about the vixen , does the objective cell unscrew I have taken out my WO 66 & 100 Ed to give the inside a clean - but the objective either had set screws to undo or was threaded & undid easily, I bryan cleaned as I would some ep or the front...I use dis h2o, winded & acetone (careful around plastic bits)
Does yours have a collimatable cell?

[hotspur]

Hi Daniel.

Yes,was in regard to the Vixen 103,and the 81 too.But mainly the 103.I am unsure what the arrangement is as to set screws or it just screws out,I think it might be the later,Not sure if its a collmitable cell.I will try and find out all that.

However since I looked last night,the issue really does not appear a major one,the specs are very small,and a couple of advanced astronomy people I mentioned this too this morning said,it really is not an issue to take a lens out of a refractor-unless really need to-and a few specs is not affecting viewing or imaging,not to worry about it.

If and when it is needed I will look at doing my self,like you have done Daniel.I have had plenty of optical instruments in my life and none have ever had any issues with been carefully cleaned,My old Leopold rifle scope is still like new after many trips in the bush and rough conditions.

On another note I picked up a 'Orion' cleaning product at astrofest last year.'Orion Formla MC' cleaner fluid for lens etc-$10 I feel its quite good,do not need much to use,a bottle would last yonks.

Cheers Chris