[Startrek (Martin)]

Need some hands on advice for cleaning my Delos eye pieces

2 of them have a very small smear when you shine my astro torch into them on an angle

I have researched a number of youtube clips, read books and viewed other forums / sources for cleaning eye pieces and all of them describe varying methods, some even say don't clean them at all as you will damage the coatings

I welcome any hands on experience and advice

Thanks in advance