elmar meters ring hard to move

[ezio gallino]

My elmar is a fine lens: there's a problem focusing ring is very hard to set. Should I try to lube or better leave it to professionals?If yes what is best oil to use? shoot this way is a very hard experience.

thanks for any hint. ezio

 

[Ben Z]

Technically the focusing helix of a lens is coated with grease, not oil. Since the helix is open to the environment somewhat, it picks up bits of dirt and crud, plus the emollient in the grease dries up, all of which conspires to make it stiff to turn. The proper servicing requires taking it apart, cleaning it thoroughly with solvent, and applying the correct amount (a little too little or too much has a great deal of effect) of the correct type (likewise very influential) of lens grease. That said, I remember DAG telling me a while ago that one or at most two drops of "light machine oil" (seweing machine oil would qualify) on the helix threads (exposed from behind by turning the lens to the close-focus, or in front--if the lens head is removable--when the helix is at infinity stop) and then working it a bit can re-emulsify the dried grease. I've done this on a few cheap lenses that weren't worth a re-lube and it works. It doesn't get rid of the gritty crud though, which can make an abrasive paste that can wear the brass helix prematurely. So I personally wouldn't go that route with an expensive lens.