gb> There is actually what appears to be a small piece of hair on the inside of gb> the rear element. I had posted several weeks back a question to see if gb> anyone has ever sent their lens to pentax to have the lenses cleaned and gb> roughly how much it would cost. But no one every replied. [...] Hi Gabriel,
sorry about it :) I didn't mean it. I hope I didn't upset you (the "ROTFL" part of my message). I will try to offer some help now :) The biggest thing I would worry about when removing rear part of lens is that quite often, the rear group is aligned individually by several screws - that's centered. Unless you have a collimator or such optical bench device, you couldn't possibly center the lens right again. I learned this the hard way :) I "ruined" (fortunately a very inexpensive screwmount) 1.8/50, by removing the rear elements assembly to clean greasy aperture. I haven't shot with it since, though (I didn't in the first place), so I don't know if it did affect the lens performance and how much. About your problem - are you sure it even affects the optical quality of the lens? Perhaps you could try alongside a good 1.9/43 LTD, what you think? I would be reluctant to have repaired a lens which performs well - it might perform worse after you get it, and it could be a hassle to prove it. I guess official Pentax repair wouldn't degrade it, though. More, if it's directly beyond the last element, on older lenses this is often held by a retainer ring which can be loosened by spanner wrench or similar tool, removing the element and cleaning it. Often, the last element is not centered individually so that it cannot be decentered, as it is cut out exactly to fit the metal around it, with the retaining ring holding it fastly in place. I have cleaned one such older lens which got hazy on the last element from inside, and it works well. I dunno however how easy or hard is it on newer lenses. It was a preset lens too, so there was no problem with opening the rear part (no aperture coupling). As a resume: I wouldn't worry about it at all, unless it really shows in the photos. Does it affect Bokeh or something? Are you sure? If it is hair-like in dimensions, it shouldn't have any effect on optical quality at all. Good light, Frantisek Vlcek - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
