Re: [Rollei] Rollei 2.8D with Problems

[Todd <todd_belcher >]

David,

The Xenotar front cell is not quite as Richard describes. The whole
front cell is extracted from the camera by the special tool he
describes, but the front element is removed by removing a small set
screw in the side of the front cell. This is a tiny set screw - so small
that it is easy to tear one side of the head off, making removal almost
impossible except by drilling out the set screw. if the set screw comes
out, then it is possible to remove the whole front cap. Grasping the
rear part of the lens cell, turn the whole front (and sides) of the
cell. The front with the engraved writing is continuous with the sides
so you can grasp the sides. This cap is threaded inside to the back part
of the cell and it is this that is holding the front element in place.
Once this piece is off, the front element is removable and all front
cell surfaces are available for cleaning. The only surfaces that cannot
be cleaned are the cemented surfaces of rear group. Look at the last
lens diagram here - the 2.8 Xenotar. The first three pieces of glass
form the front cell.

http://www.rollei-gallery.net/-todd/image-41289.html

todd




David Grasby wrote:
> 
> Thanks for the advice Richard.
> Maybe I should just it to you instead.   :-)
> Regards,
> David.
> 
> ----- Original Message -----
> From: "Richard Knoppow" <dickburk  >
> To: <rollei  
> Sent: Wednesday, April 02, 2003 8:44 AM
> Subject: Re: [Rollei] Rollei 2.8D with Problems
> 
> >
> > ----- Original Message -----
> > From: "David Grasby" <david.grasby  >
> > To: <rollei  
> > Sent: Tuesday, April 01, 2003 2:22 PM
> > Subject: [Rollei] Rollei 2.8D with Problems
> >
> >
> > > Dear Fellow Rollei Users,
> > >
> > > I have a 2.8D with a 80mm f2.8 Xenotar lens. The camera is
> > in lovely
> > > condition, but the lens has 'haze' problems.
> > >
> > > I sent the camera to a techie but he only works on bodies
> > and couldn't cure
> > > the haze problem but he did loosen the front element so
> > that I could send it
> > > away for repolishing.
> > >
> > > Now, I removed the front element and the haze is not on
> > either the front or
> > > rear of the lens, but in the middle. I know precious
> > little about lenses,
> > > but I assume the front element of the Xenotar is a
> > doublet(?). Does anyone
> > > on the list have any idea about what could be causing the
> > haze and whether
> > > it is possible for it to be repolished? Is this likely to
> > cost more than the
> > > camera is worth (I paid $300AUS ($180US) for the camera)?
> > > Cheers,
> > > David.
> > >
> >
> >
> >    I think you mean front _cell_ not element. The front cell
> > has two lenses in it. The front lens is a single element the
> > rear lens is a cemented pair of elements. Most likely the
> > haze is on the glass-air surfaces inside the cell. The front
> > element can be removed by unscrewing the retaining ring at
> > the front of the cell. Schneider retaining rings have slots
> > for a special tool to remove them. They can also be removed
> > by using a friction tool made of a tube the right diameter
> > with a sticky rubber ring cemented to one end.
> >   You can make a suitable spanner from sheet metal, that's
> > preferable to using an adjustable spanner since it is much
> > less likely to slip and scratch the lens surface.
> >   The haze will clean off with lens cleaner or window
> > cleaner.
> >   The rear cell also has two air-spaced elements in it and
> > is also probably hazy.
> >   It is possible, but much less likely, that the haze is
> > from defective cement between the two elements of the rear
> > lens in the front. A flashlight shown into the lens will
> > generally help to distinguish between haze and bad cement.
> >   I don't know the exact source of the haze. Its very common
> > in older lenses. I suspect it comes from evaporation of
> > something from the anti-reflection paint inside the cell.
> >   If you decide to disassemble the cell pay attention to any
> > spacers which may be under the element. I don't think
> > Schneider uses these on Xenotars but they do on other
> > lenses. They must be replaced in the right place and with
> > the correrct orientation.
> >
> > ---
> > Richard Knoppow
> > Los Angeles, CA, USA
> > dickburk  
> >
> >

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