Posted by dh on 08/09/07 19:50

On Thu, 02 Aug 2007 07:45:03 -0700, Richard Crowley <rcrowley@xprt.net> wrote:

>dh@. wrote:
>> We have JVC GY-DV500 cameras. I couldn't find a
>> model number on the lens itself, but the zoom unit
>> mounted on the side of the lens says:
>>
>> Fujinon S20 x 6.4 BRM-SD
>> 1:1.4 / 6.4-128mm
>>
>> I don't know what all that means yet.
>
>It is the model number and contains several key pieces of
>the specification (such as the zoom ratio, minimumm F-
>stop, type of camera attachment, etc.) It is easy enough
>to decode these numbers by browsing the Fujinon website.
>
>> The lens has
>> holes that look like they have threaded inserts in them,
>> for securing the manual focus unit etc to the lense with
>> a bolt. If they really are inserts in the holes, is it possible
>> to replace them? We have some that are broken off at
>> the outer end, so the bolt will no longer reach it.
>
>It might be possible that they used something like
>"Helicoil" thread inserts which allow you to replace the
>threads.

That's what I'm hoping.

>But you may have to consider having the lens
>repaired by Fujinon or some experienced lens technician
>as they are too delicate and expensive to trust to your
>average mechanic:-)

Maybe I'll take it by Wolf Camera or something just
to see what those guys say about it.

>> Also, is it possible to get an iris control to mount on
>> the tripod handles? We have one for zoom and
>> focus, and it would be great to have one for iris too.
>
>Why? They don't typically provide iris controls for the
>camera operator (for a number of reasons). The iris is
>usually controlled electronically by the camera

We tried, but the camera likes it too dark. Is it
possible to adjust how light or dark the auto iris
function makes it?

>(or
>remotely by the camera control unit, etc.) The camera
>operator is rarely able to properly judge/adjust the iris
>which is why we usually either use the automatic
>exposure function of the camera (in single-camera
>shooting situations), or a person back in the control
>location will adjust the iris (and other parameters) of
>all the cameras in a multi-camera production.

We're not set up for that. We're projecting whatever
band we have on stage up onto some big screens, so
we can see the result. The lighting isn't even across
the stage, so in order to get decent shots we have to
be able to control the iris. One guy is sitting on a riser
running his camera, and is in an easy position to reach
the lens. I'm standing on the floor running the switcher
and the other camera which is also on a riser, so I can't
reach the lens. I can zoom and focus with the same
hand I'm moving the camera with, but in order to adjust
the iris I have to get up on the riser which is a real pain
in the ass. Getting iris control down on the tripod arm
too would make it great.

>Some cameras have a small control panel that you can
>plug in which include the iris control and can be mounted
>on the tripod arms.
>
>For example I have a Sony RM-M7G control unit for my
>Sony DSR-300 camera. Here is a picture...
>http://www.globalmediapro.com/av/attach/192/index-1391.jpg
>The iris control is the large black knob in the lower right.

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