Thanks Fred! The baffle on these lenses comes off quite easily with 2-3 screws. I won't have to risk doing it on the lens. I've used a "cut-off" wheel in the Dremel for stuff like this before, works quite well. I wanted to make sure removing part of the flange wouldn't cause any problems down the road. I assumed it was just there to protect the aperture lever and served no other important function. But, you know what they say happens when one ass-u-me s! ;-)
Don > -----Original Message----- > From: Fred [mailto:[EMAIL PROTECTED] > Sent: Monday, October 25, 2004 6:35 PM > To: Don Sanderson > Subject: Re: Older Series 1 lenses on the ist-D > > > > I have several older Vivitar lenses I'd like to try on the D. > > Problem is the flange that protects the aperture control lever on > > the rear side won't let them mount. Does anyone know of any > > downside to cutting this flange down to the size it is on newer > > lenses? It'll probably wreck the resale value but I'm really > > curious to see how they do on the digi. > > Below is a a description of the procedure, along with a couple of > pix. There's really nothing "fancy" about the procedure, except you > want to keep aluminum filings out of the lens innards. > > Unfortunately, the "original" line (mid-1970's) of VS1 lenses had a > "generous" amount of baffling at the mount end, which causes > problems with some K-mount bodies (and I think that the LX is the > oldest body that is not happy with the extra flange these old lenses > have). Here are some image links illustrating the removal of this > flange: > > First, here are two VS1 35-85/2.8's, the left one of which shows the > extra baffle, while the right one has been modified - > <http://www.cetussoft.com/pentax/v358528/1ofeach.jpg> . > > Lacking access to a bench grinder, I resort to simply cutting of the > excess baffle material with a hacksaw (but leaving the protective > "hump" near the coupling lever, as in jen-you-wine Pentax K-mounts). > (Another PDML-er reported using a thin file for this procedure.) I > don't try to remove the baffle entirely, but I leave about a mm or > so of it still sticking out (since trying to remove all of it would > tend to scar up the face of the K-mount flange, and removing it > entirely is not really necessary, anyway). I then smooth off the > remaining edge of the baffle with a fine-toothed file, and finally I > touch up the exposed (shiny) metal edge of the remaining baffle area > with a black "magic marker" (for a little flare prevention). > > It is important, of course, to mask off completely the rest of the > lens when the extra baffle is being removed from the lens (since you > don't want any little aluminum filings "adding" to the lens' innards > - <g>) - <http://www.cetussoft.com/pentax/v358528/lensmod.jpg> . > > It is also possible to ~carefully~ remove the K-mount flange from > the lens and then remove the extra baffle after masking off only the > flange - <http://www.cetussoft.com/pentax/v358528/flangmod.jpg> . > > I've used lenses that still had the extra baffle protrusion on the > KX, the ME Super, and the Super Program, but I've found that the > flange does come quite close to impacting the upper mirror box > baffle in the LX (when first inserting the lens mount into the body, > before twisting/locking it into position), so I've routinely > performed this "surgery" on some of the "original" VS1 lenses (and, > believe me, it is indeed worth the trouble for some of 'em - <g>). I > suspect that this procedure would be necessary to use any of these > ol' classics on most (if not all) of the newer autofocus bodies, and > probably on the digital bodies, I would think. > > Fred > >
