ED80 lens cell removal

[JamesF]

I've just noticed that the inside face of the objective unit on my (gold) ED80 is quite disgustingly filthy, so I want to clean it.  It's not obvious how the lens cell is removed however.  I'm assuming it just screws off the end of the tube, but if so it's very stiff.  Is that correct, or have I missed something?

James

[Skipper Billy]

It just unscrews - I accidentally unscrewed mine by accident when I was trying to get the dew shield off !!! I now know that the dew shield is just a push fit and the lens cell unscrews (normal direction)

I would get some advice on cleaning it before you remove it though !!  Scary stuff!!!!!

[JohnC]

I did this on the old blue one. It was very stiff at first.

Once off I thought the thread was quite rough so lightly oiled it.

Went back on a lot easier.

Best regards

John

[JamesF]

Thanks chaps.  Time to dig out the baby boa then

James

[Skipper Billy]

PS - when I accidentally unscrewed it there was some sort of sealant/threadlocker on the threads which had gone hard with age - some of it fell off (down the tube!) and another piece attached itself by static to the inside of the lens cell.

Just something to watch out for !!

[JamesF]

No threadlock on mine, fortunately.  Having taken PST bits apart recently I am absolutely not a fan of threadlock

Now I've got rid of the dust and hair from the inside of the lens unit, it appears that there's a bluish reflection from between the lenses.  Not sure what that is or whether it's possible to clean it, but it's not too bad so I intend to leave it for the time being.

James

[NGC 1502]

No threadlock on mine, fortunately.  Having taken PST bits apart recently I am absolutely not a fan of threadlock

Now I've got rid of the dust and hair from the inside of the lens unit, it appears that there's a bluish reflection from between the lenses.  Not sure what that is or whether it's possible to clean it, but it's not too bad so I intend to leave it for the time being.

James

Hi James, taking off the lens cell as a complete unit is usually no problem, but removing the lens elements from the cell is quite another thing, so if it were me, I'd live with any minor haze or whatever between the elements ( as you are suggesting ) it's not likely to cause any issues.

Regards, Ed.