By Bill Dellinges
The LensPen is an interesting idea. Combine a lens brush and lens cleaner in a pen-like format. I got mine from Eagle Optics as a gift for spelling their vendor when he had to go to the bathroom at a bird conference in Bisbee-but I digress. They cost about $8 and can be found almost everywhere. No way was I going to test it on a $300 Nagler eyepiece, so I used an older eyepiece in my collection as a guinea pig. Hereís the deal: on one end is a retractable brush, use this first to get any particles off the lens before cleaning it to avoid scratching the lens (a standard procedure). Removing the cap at the other end reveals a Ĺ" diameter felt pad. This pad gets its cleaning agent from a solid plug of the stuff at the end of the inside of the cap (got that?). I intentionally mashed a finger print and pressed my eye against the eye lens of this unfortunate eyepiece to "dirty" it. Guess no one will ever buy an eyepiece from me again after reading this.Will the LensPen clean this mess up? I brushed off the lens. I then followed the instructions and gently pressed and moved the penís pad about the lens. It removed the print and oils pretty well. I did note, however, it left a sleek-like film on the lens surface which could be detected if you held it just right in the light. Now what? I got an idea. I put the cap back on which gives the pad another dose of cleaner and then repeated the cleaning procedure. This seemed to do the trick. The eyepiece was now as clean as it was before. So maybe it takes two applications for really dirty lenses in order to remove "sleeks" (?). Anyway, Iíd have to say the thing works but I would use it only in emergencies, preferring the orthodox method of isopropyl alcohol and tissues. Since I had to use a somewhat firm pressure on the lens while cleaning it, Iíd be reluctant to try it on expensive eyepieces unless I had no choice, like removing a greasy finger print in the field where it might permanently etch itself into the coatings before you could get home to clean it (better option: keep a lens cleaning kit with you when using your scope). This product is designed for small jobs like eyepieces and camera lenses. I donít think you want to try to clean a 14" SCT corrector plate with it unless you have a long life ahead of you.