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    #11
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    It was absolutely perfect- never mind ;-)


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    #12
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    Quote Originally Posted by optitek View Post
    It was absolutely perfect- never mind ;-)
    I don't understand your comment. Splain it for us.


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    #13
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    ggrantly,

    My DVX100A is perfectly sharp from end to end, as were the HMC150 and HVX200A cams I've used.
    The zoom lenses on these are parfocal, in the sense that the software component of the focusing system corrects for any minor "mistracking" issues as the lens is zoomed.
    Mass produced lens assemblies like this with a number of lens element groups, often need some internal computer help to keep them in focus throughout the range.
    I'm pretty sure that the integral zoom on the OP's camera works the same way.

    As JB notes, the back focus must be set correctly, and a proper back focus check is one of the first things I'd do when buying or renting a camcorder with built in zoom.

    Hopefully, back focus "tweaking" on these newer lenses can still be done electronically via a software alignment, unless the assembly itself is damaged.

    However, since Lance's post asked for service center suggestions, I hope my earlier reply was of some help.
    Don't know where your located, but if Digitron in L.A. can't fix it, no one can (I think Eric is still the go-to guy there).

    Ken


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    #14
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    Quote Originally Posted by ggrantly View Post


    And in fact, if the OP's lens is not parafocal, then focusing via that technique will never work.



    So what part of my response is incorrect?
    I think the confusion comes from the described symptom that COULD be because the lens isn’t back focussed correctly OR it could ALSO be because the lens isn’t parfocal. We don’t know for sure with this specific case if the lens is parfocal. I’m certainly used to built in lenses on handycams being parfocal.

    JB
    Cinematographer
    Sydney Australia
    www.johnbrawley.com
    I also have a blog


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    #15
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    Quote Originally Posted by ggrantly View Post
    I don't understand your comment. Splain it for us.
    To paraphrase my favorite musician:
    "IT AIN'T NO POINT TALKING WHEN NO ONE IS LISTENING"


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    #16
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    Thank you for the recommendation, I'll check them out!


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    #17
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    Ggrantly: This is a fixed lens. In my experience, every video camera I have ever owned with a fixed lens is parfocal. I've never had a camera with this issue and I've owned nearly 20 cameras over the past 20 years. Yes, I do have focus aids on the camera but we are an event based company and as such we need cameras to hold their focus...for example we are shooting a dance recital. One camera is responsible to hold the group...which expands and contracts from as wide as the stage to less than half the stage. A camera that can't stay in focus through that zoom range would be useless to our crew.


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    #18
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    Any of the fixed lens PannyCams I have owned have lost a couple stops (roughly) of sensitivity between wide and long views. If you go from f/2 to f/4.5 your depth of field is going to change. Even if the lens is "parfocal", if the DOF changes while zooming, can you necessarily expect the lens to hold focus? Maybe, maybe not. It is a distinction without a difference if the image softens.

    Despite some differing opinions posted here, in my experience with the PannyCams I have owned, I wouldn't be able to make significant zoom in or zoom out moves without tweaking the focus unless I was using a small aperture to increase the DOF. And smaller apertures, beyond f/8 or so, will significantly soften the image on virtually all Handycam lenses.

    G

    Edit: No doubt when we moved past the standard def DVX100 series to the high def HVX and HPX cams, critical focus became more challenging.


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    #19
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    Quote Originally Posted by ggrantly View Post
    Any of the fixed lens PannyCams I have owned have lost a couple stops (roughly) of sensitivity between wide and long views. If you go from f/2 to f/4.5 your depth of field is going to change. Even if the lens is "parfocal", if the DOF changes while zooming, can you necessarily expect the lens to hold focus? Maybe, maybe not. It is a distinction without a difference if the image softens.
    Yes. Most high zoom ratio lenses have iris ramping going from wide to the top-end. My three Fuji Premiere HD's (13x, 13x, 22x) and Canon 17-120(7x) all hold focus. If it's a parfocal lens, you nailed focus, back-focus is set properly, there's nothing "wrong" with the lens and the object or camera doesn't move in relation to one-another after focusing on it, focus should be the same no matter where you are in the zoom range. If this were not the case, then what most of us do with ENG and other (parfocal)zoom lenses, zooming in to get critical focus on your subject and zooming back out to set the shot while maintaining focus, would not work.


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