Hi Olaf,
> Yesterday Frank van Lindert suggested me the same approach, I tried it and
> it easily unscrews. That is as far as I have gone so far (i.e. I didn't
> remove the shade from the lens, I just unscrewed it). I suppose the shade
> hood can then simply be removed by pulling it off?
Yes, the shade has to be pulled off. Rotate gently and pull.
>
> Hmmm, basically what I am referring to is when you look into the lens from
> the front, you will see the front element (i.e. the first "lens", this is
> what I meant with the word "element") and some 4-5 centimetres below that
> you see the second one, the latter one is the one with the fungus.
By looking from the front is difficult to say exactly where fungus is
(assuming you have not a wide experience in cleaning 300 lenses yet). Before
you unmount the frontal elements my suggestion is to detach the frontal
group that is fixed with three or four screws only. It is much more exposed
to fungus, imho, and it is easier to unmount and remount.
>
> Now, for the rest of the process (i.e. after removing the shade hood):
>
> For removing the "lens info ring" which holds the first element in place
> (i.e. the "inside" of the filter ring, where it mentions stuff like: "MC
> 300mm Olympus" etc.), Frank suggested to use a rubber ring of the same size
> to evenly apply pressure and prevent shooting out over the lens with a sharp
> tool. This idea is clear, however two small questions:
> 1-Do I first have to remove the screws you mentioned (i.e. the ones that are
> located under the shade hood)?
Yes, they are there. You'd try to remove them first after removing hood. Try
this before attempting removing the info ring.
> 2-When removing these screws, what happens exactly (more specifically, will
> the complete housing be loosened, or will something fall apart, or...?!?)?
In my sample after that the frontal part of the lens is detached and may
fall. Be sure to grasp with hands and gently pull the parts in order to get
the two half-lenses. John Hermanson who is by sure more expert than me (I
saw my 300 only while he has been repairing camera and lenses for years)
points at the fact that the lens parts may be glued too.
>
> After this ring has been removed, I guess the first element is completely
> loose and can be removed, right? If this is the case, and I remove the first
> element, will there be any awkward pieces coming loose, or are there any
> other things I should take particular care with?
After you have the two half-lenses you will find the surfaces of the glass
dirty. clean them and it is likely you are done. If you still see dirty
inside groups then you have to go further.
>
>
> O.k., I have heard that Pond's cream may not be available in The
> Netherlands, so maybe I have to go for one of the things you mentioned. Do
> you know if any of these substances can damage the coating (FYI: my lens is
> a multi-coated version)?
I think/hope the liquids I mentioned do not damage coatings. Be sure to pass
a clean cotton cloth on a humid surface only.
>
> Well, supposing the cleaning process goes as described above, there will be
> a few potential pitfalls left:
> -Getting a dust-free environment;
> -Re-assembly of the lens;
> -???.
>
> If you have any advise on these, it would also be more than welcome,
> especially considering the re-assembly of the lens, is that a
> straightforward process, or is it tricky with having to align all sorts of
> things before screwing it back together, etc.?
Vacuum clean the room in which you work and see it is not too dry. There are
no little elements (besides screws) that can be lost. Use the right
screwdriver (the bigger that fits in the gaps) and if the screws were too
tight put a drop of an appropriated oil, let it work and try to
screw-unscrew pressing firmly till they start moving.
>
Marco
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