video assist breakup

[mark morgan]

while using my modulos 3000 on a arriflex sr2,

picture is solid until we begin to record,

then the picture breaks up or is unusable on the video assist monitor

even the monitor on the rig seems to go a little more dim when recording.

bnc "t" going to modulos and monitor on the rig

[Erwin Landau]

Hi Mark,

 

Just to clarify... Are you talking when the camera is rolling or when you try to record video on the video assist???

I assume you are talking when the camera starts rolling (film) the video gets bad right? What kind of video-tap are you using? Are you powering the camera from the rig or from the onboard battery?

 

The SR2 is a 12 volt camera and generally the black ARRI (12 volt) cameras had shielding and grounding issues. The image is always noisy. (I blew up a 35-3 once by touching it while rolling it closed the circuit and fried the breaker and melted one of the pins in my cable... also happened with a 2C with a CE base... put in the smell of burned material here...)

 

First you can try to power the camera from the 12 volt only side of your rig (depending on what rig you own, if you own a multi battery set up) it will use a different battery that is not powering the video components as well. Better yet use an onboard battery which separates the power completely from your sled. It should get you a way better picture to your sled and video village.

Also try and get power to the video tap separate from the camera (do not power it from the camera body). Try to isolate the video and the power source as much as possible... power it from the rig.

 

That usually takes care of the problem. Unless you have a modern video assist there will always be artifacts like lines or jerks going on in your monitor... (While the camera is rolling)...there is a reason why ARRI went to the SR3 and all of them as of late are retrofitted with 535 IVS video systems...

 

Hope that helps,

 

If not, call me, you have my number.

 

Erwin

 

PS: Just saw that you are using a T... if you are using the cables that I send you for power, then you are feeding a double video signal to the Modulus and you are double terminating the image (turning it dim or very dim and crappy). Power and video are coming from the 4 pin Lemo (or 4 pin Hirose) into the 6 pin Hirose (Transmitter side). No BNC to the transmitter is needed if the rig is wired properly.

A separate BNC is going from the video assist directly to your rig, that's the main video into your rig, to your monitor and out the Modulus to video village...