Secrets of the JVC GY DV5000 Tip#3-ALC secret

[Lou Bruno]

In the GAIN menu , the camera operator can set the gain from -3db,0,3.6.9,12,15 and 18. There is also a setting for ALC. This ALC mode is also located in the same Camera Process menu as the gain functions. All of these gain functions as well as the ALC mode are activated by pushing and holding the STATUS BUTTON and scrolling to the Camera Process Menu. The camera operator can then choose via scrolling and setting the gain of any of the aformentioned gain/ALC settings in the submenu.

ALC or Automatic Video Level Control is a function whereby the Extended Electronic Iris (EEI) finds a perfect exposure via using the VARIABLE gain and IRIS together. The ALC is a very underused exposure setting. A perfect example of how it works would be acomplished by taking a "shot" of a church steeple against a blue partly cloudy sky. The picture is actually adjusted to compensate for both exposure and backlighting. The results of this "shot" will produce a fine quality picture where the steeple, sky and clouds are ALL discernable and exposed properly.

BUT HERE IS WHERE THE PROBLEM OCCURS


For those videographers who "shoot" under low light conditions, the ALC increases the gain all the way up to 18db after exhausting the iris and shutter speeds to allow more light. When this occurs, the camera then raises the electronic gain. as a result, dark areas are introduced as video noise and grain-JUST LIKE FULL AUTO MODE. For instance, backgrounds which are normally dark in a badly lit areas and night shots will display grain in those areas. Not pretty!!!

It should be noted that ALC is sought of an automode BUT the videographer can still use MANUAL WHITE BALANCE AND MANUAL IRIS if needed.
This is unlike FAS where the camera is ALWAYS set to Full Auto White Balance (FAW)and the user is virtually locked-out on "auto pilot". In other words, the camera iris can not be put into manual either.

WELL- here is a solution which will DECREASE the ALC default setting. The below procedure will allow the user to limit the "db boost" from 18db -all the way down to a useable 9db. Great for outdoor night videotaping.


PROCEDURE

1) PRESS LOW LUX,FAS and STATUS BUTTON at the SAME time.

2) A SERVICE MENU WILL APPEAR

3) Using the SCROLL button or SHUTTER WHEEL, place it next to CAMERA 1

4) PUSH the SHUTTER WHEEL IN

5) SCROLL to the ALC

6) PUSH IN the ALC using the SHUTTER WHEEL

7) Set the ALC to 9db and PUSH to SET the ALC mode.

8) Push STATUS button to return to normal operations.

That is all there is to it! Now-look at the difference!!! NO MORE OVERWHELMING GRAIN!!!!!!!!!!!!!!!

NOTE: However, keep in mind that this setting NEVER seems to limit the camera while in Full Auto System only ALC.

STAY TUNED FOR MY NEXT TIP----I FOUND A MENU SETTING WHICH WILL SAVE YOU MONEY IF BUYING OR PURCHASING A USED OR REFURBISHED JVC GY DV5000.


LOU BRUNO

[Jeff Donald]

Thanks, Lou.