Now that I have your attention :-) I'll bet many of you are saying "no
way!" Where there's a will, there's a "way!"
Anyone familiar with both the Zuiko 90/2 2:1 macro and the Zuiko
teleconverters knows they don't fit together, because the rear-element
protection tab on the 90/2 gets in the way. However, you don't really need
this tab, because:
1) the rear element is already inset, and can't contact a flat surface
placed against it, but more importantly,
2) what kind of fool lets anything other than a camera body or a cap get
close to the rear element, anyway? :-)
It really didn't take that much nerve to modify an $800 lens. I was a
prototype tech for years, and still do a lot of custom mechanical work. In
fact, I often get more pleasure out of "improving" something than I do
using it afterward!
First, I made a simple jig out of some oak scrap that would both support
the lens in a vise and serve as a grinding stop. A 3" hole saw works nicely
for this, and after you pad it with carpet, it holds the 90/2 snugly by the
focusing barrel. You'll want a 2" thickness in order to use it as a
grinding gauge.
Then, focus the lens all the way in to 1.3ft., retracting the sensitive
rear element well out of reach of sharp tools. Cover the rear element
opening with blue tape, as close to the protection tab as possible.
Clamp the lens and jig into a vise, making sure the protection tab is on
top. This will minimize filings falling into the tiny opening between the
straight tape and the curved tab. Position the jig about 2.5mm past the
base of the tab -- you'l be removing about 3mm of the tab.
Using a sharp file, cut the tab down until it is level with your jig.
Loosen the vise, slide the lens further out of the jig, re-clamp, and
carefully dress the remaining tab with a jeweler's file. Touch it up with
flat black paint.
The 90/2 and Zuiko 2x teleconverter will now focus from 1:1 to infinity!
You can even stack the 2x and the 1.4x to build a 250mm, f5.6 0.7:1 macro
-- my initial impression is very good. I'll put the JPEGs up when the film
comes back.
Important Stuff:
1) Use hand tools, NOT Dremel-type tools! They throw tiny bits of metal
everywhere. The filings from a hand file are larger, more easily
controlled, more easily cleaned up, and less likely to get into places
you'd rather they not be.
2) Go easy on the vise! Use just enough pressure to secure the lens. Use a
jig to distribute the pressure, rather than a rag, which will protect the
surface, but will only apply pressure on two points.
3) It's better to take off a bit too much than too little. As mentioned, I
think the tab is fairly useless anyway, and taking off too little can
scratch up the inside of the teleconverter. With 2.5mm remaining, the tab
will be flush with the rear element holder at infinity focus.
4) This modification also allows you to mount the 90/2 on the Zuiko 1.4x
teleconverter for a 126mm, f2.8 1.4:1 macro, but YOU CAN NOT FOCUS TO
INFINITY because of the protruding front element in the 1.4x. If you're in
the habit of rapidly focusing, you may damage or mar either or both the
90/2 and the 1.4x.
If you don't have the facilities, skill, or confidence to do this mod, I'll
do it for $50 plus shipping, results guaranteed. Although I take great
care, and modified my 10- condition lens without incident, I'm not willing
to do this to new or mint lenses without indemnity for minor scratches and
scuffs.
: Jan Steinman <mailto:jans@xxxxxxxxxxx>
: 19280 Rydman Court, West Linn, OR 97068-1331 USA
: +1.503.635.3229
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