Power Zoom on the 12-50mm Lens Adjustment and Control Issues

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BoltSnap

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My problem with this "power zoom" is the fact that the lens keep changing zoom without stopping until it reaches the end of the range (either direction) even with very little turn. It is very difficult to get the lens to zoom to the exact focal length and I end up turning the zoom knob back and forth to get the lens to come to the value I want or, most of the time, close but not exactly.

Does anyone know what am I doing wrong here and how I should do it please?
 
Burhan, It should not be behaving that way. The gear is spring loaded so that you turn it to zoom and it "springs back" to the neutral position (no more zooming) if you release the zoom knob.

In fact, as you first begin to zoom, you engage "slow zoom" mode which is for zooming during video or very small changes in focal length. With the slight turn of the knob the zoom is slow and precise and you should not have much "back and forth" needed, if any.

You have to crank the knob more, and with a more definite effort, to switch into "fast zoom" which takes you through the range with much more speed. If you do that and overshoot the length you want, you turn the know slightly the other way to fine-tune back to the length using slow zoom. It should be very intuitive after 4 or 5 dives. You do need to use it a bit to master it.

The zoom, however, should never just, on its own, zoom through the entire range even when you have released the knob.
 
You mean that it should stop zooming when I take my fingers of the zoom knob?

---------- Post added February 7th, 2013 at 01:02 AM ----------

I justed tried it with the camera outside the housing using the Nauticam gear on the lens and it seems that even if I turn the zoom gear slightly and let my fingers off the gear, the lens zoom continues to change until it reaches the end of the zoom range in that direction. The only way to stop it is to turn the gear in the opposite direction. This may make it stop or move in the opposite direction to the end of that zoom range.
 
My guess is that in step 2 of the gear installation guide, that either it wasn't installed tight enough onto the lens and is slipping, or that the gear wasn't aligned exactly as shown with the lens. It's possibly somewhere else, but this would seem to be the most likely problem that could cause this behaviour.

What should happen is that the knob on the camera appears to be spring loaded (because the gear is), and so if you turn it right of left it will zoom in/out but will always return to it's initial position and stop zooming.
 
Two very good points have been made here by uncle bob and Guy. First that you may want to start over and reinstall the gear to be sure that is not the problem. The second is time in the water with your equipment. While I encourage students to use their equipment out of the water or in a pool until they have a chance to go diving, control of the camera in the water takes time. I am sure it took you some time to learn the features of the camera out of the water and with time in the water you will gain more control as well. I now feel like I have more control of the camera in my Nauticam housing than I do above water now that I have made a number of dives with it. Less time on Scubaboard and more time in the water will make us all better photographers.

Phil Rudin
 
Thank you for the links but have you tried to access the files? I get a message that says:


"[h=2]Page Not Found[/h] The page /user-manuals/36147 O1250-Z Olympus M.Zuiko 12-50mm F3.5-6.3 EZ zoom gear-1.pdf could not be located on this website.
We recommend using the navigation bar to get back on track within our site. If you feel you have reached this page in error, please contact a site operator. Thank you!

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