That depends, Albano. If you want to clean the front elements, all you have to do is remove the decorative ring in order to have access to the front groups. They are probably screwed in place as a unit. To have access to both sides of each element, there will probably be retaining rings. By the way, do you know how to remove that decorative ring? I'm not familiar with that particular lens, but if you don't manage to unscrew the front group, you'll probably have to remove the front barrel, which can be easily done by removing three (it's always three, I guess) screws that fix it to the front of the helycoidal (is that the correct spelling?) tube. On the other hand, if you need only to lube the aperture ring, all you need to do is unscrew and lift the mount. After that, simply pull the ring up --- with the lens facing down --- being careful not to loose the little sphere that's responsible for the aperture "clicks." Some lenses will allow you to clean the rear elements simply by unscrewing it, without even having to remove the mount; I'm not sure about the M 100/2.8 (On some other lenses, dismantling everything starting from the front is the easiest way). I don't have a lot of experience opening lenses --- so far, I have only tackled primes --- but, IMHO, the most important things are: lots of attention; a clear place to do the job; a good source of light (after all, most parts are small) and the tools (mostly tweezers and inexpensive precision screw drivers, mainly Phillips ones). Maybe some latex gloves --- they help prevent the fingertips that you only see when everything is put together again...:-) The process itself is relatively straightforward. I hope this can help you. Eduardo.
----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, March 07, 2002 2:21 PM Subject: How to clean a 100 2.8? > Hi, gang > I would appreciate some info on how to open and clean a M 100 2.8 lens. > It's done by the front? The elements are secured in groups? > I don't mind about losing "factory precision" since I know it was already > open by previous owner. > Thanks in advance. > > AG > - > 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 . - 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 .
