On 1/11/2012 3:34 PM, Chuck Norcutt wrote:
> No, I don't see the problem the makers have. All of these lenses fit
> all of my OM bodies perfectly. The maker only need make the mating lens
> flanges to the same specification as OM bodies. They're probably off by
> 0.001-0.002 inches. A large error for a good machine shop.
OK, let me revise what I said.
"You can see the problem the makers have without raising the price
considerably. The same adapter is a good fit for
Zuikos, too tight on a Vivitar and too loose on a Tokina."
Now get out your flashlight and magnifying glass. Look closely at the inside of
the mount on an OM body. See those
separate little springs screwed to the mount? Stainless steel mount with spring
steel springs to hold the lens flanges.
To sell an adapter for under $20 (your previous stated limit), with chip, the
adapter is made of one solid piece of
brass, with two screws in it, a lens stop and an aperture stop down. The
flanges that hold the lens flanges have a kerf
cut in them to allow them to flex and provide tension to hold the lens from
turning.
Such a design simply doesn't have the spring range to accommodate as wide a
range of lens flange widths and depths as
the more complex one on OM bodies. The design is nothing new. Inexpensive
teleconverters and extension tubes from the
old days are made the same way. The Oly teleconverters and extension tubes use
the same, far better, but more expensive,
design as the bodies.
The focus confirmation chips used to be available separately, with a little jig
for mounting them correctly. Perhaps you
might separate the purchase of adapter and chips. You already have one adapter
that fits all the lenses.
As you have said you would be happy with dedicated adapter/ship combos for each
lens, how about custom modifying
adapters you already have? As long as the problem is that they are too tight,
simply reduce the mating flange surfaces a
little. You don't need a shop to sand/file/dremel/whatever each one just a
little, test fit, repeat as necessary. Sort
of like exposure determination by chimping. :-)
My first adapter was a home made brass one with no plating. This was at the
beginning, and all adapters were quite
pricy. Home made and used brought down the price of the experiment of trying
OMs on a D60 borrowed from a former list
member before springing for a 300D. the results convinced me.
<http://galleries.moosemystic.net/D60/> I wonder what I could do now with those
images with such better tools and
greater experience.
The brass was a bit too soft. Worked fine with small lenses. A big, heavy one
would soon feel loose on the camera. Twist
a small screwdriver in the kerfs, and it would be fine until I used another
heavy lens. I cut and stuffed tiny pieces of
sheet aluminum into the kerfs. Worked like a charm. Still works, although I
have other, better looking adapters now.
I can just see Chuck, sitting in a rocker on the front porch of his trailer,
whittling' away at his adapters. :-P
Sittin' on the porch, retellin' old lies,
Moose
--
What if the Hokey Pokey *IS* what it's all about?
--
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