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isw isw is offline
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Default Does anyone know how the retracting mechainsm works on a (Nikon) digital camera?

In article ,
Amanda Riphnykhazova wrote:

A Coolpix S9300 was dropped on the lens when I had had it for n a week.

The front metal piece containing the lens cover is severely dented and came
off.But the rest of the camera looks fine. However the unit was left with the
lens in the out position and wouldn't retract. (actually with a lot of
playing with it, the camera works but the non-retracting lens now wont focus
on the working screen.

That piece cant cost all that much and must be easy to fit. It looks as if it
just pushes on to the front of the forward cylinder. Has anyone any
experience of this please and should I take it to a local repair shop which
can buy the parts from Nikon if the repair is that easy?

The problem, obviously, is that I have spoken to the shop and whoever answers
the telephone there tells me that they send all Coolpix repairs of the
slightest complexity back to Nikon (who will charge more than the $100 which
the camera is worth to repair it)

Does anyone know how these retractable lenses work please? There is a pin
going into the lens which activates the lens cover. Does anyone think that
putting the front piece back on will suddenly activate the electronics
governing the whole lens again please?


I'm not familiar with Nikons, but I've repaired the lens assembly on a
number of Panasonic cameras, and I expect they are similar inside.

There are a number of nested tubes, some hollow, some with lenses
inside. The outside of the tubes have three (usually) pins sticking out.
The inside of each tube has matching grooves into which the pins of the
next smaller tube fit. The outer tube has a gear sector on the back, and
a small reversible motor is used to cause it to rotate. As it rotates,
the grooves and pins cause the tubes to extend or retract, sort of like
a nut on a bolt. The grooves follow a very non-linear path, which causes
some of the tubes to move at a different rate than the others, in sone
cases even "backwards" (retracting when other tubes are moving forward).

As you might expect, the pins are small and fragile and the grooves are
shallow. Forcing the lens inward will at least cause some of the pins to
jump out of their grooves, and may actually cause some to break off.

From what you said, it sounds like the lens of your camera has been
jammed in that way.

You might try *gently* rotating the lens while pushing and pulling, to
see if any displaced (but not broken) pins might be persuaded to slip
back into their grooves. I managed to fix a Panasonic camera that way
*once*.

If you send the camera in for repair, it's almost certain that the
entire lens assembly (which includes the auto-focus, zoom, and image
stabilizer mechanisms, and the photo sensor) will be replaced. You're
probably correct, that the actual piece that broke is only worth a few
cents, but the labor involved in getting to it would be huge.

If you feel comfortable working with tiny screws and other components,
paper-thin electrical cables, etc. it is possible to take a camera
apart, disassemble the lens mechanism, glue broken pins back in place,
and put the whole thing back together. I've done it, but for my own
"amusement"; there could never be any money in it. At any reasonable
hourly rate, a new camera would be a lot cheaper.

Isaac