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Unread 07-02-2010, 18:24
Bigcheese Bigcheese is offline
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[HOW TO]Removing motion blur on the camera by forcing a low exposure time

As anyone who has setup the AXIS Camera knows, there is no way to set the exposure time explicitly from the setup web page. I needed to force the exposure time down in order to keep tracking this years target while moving, so I looked around on the file system and figured it out.

There are three values that have an available settings of "Hold Current" that are saved between power cycles. These values are simply stored on the file system under /dynamic/image.conf (it may be slightly different, but I don't have the camera with me at the moment). It is a text file with three lines:

Code:
HOLD1=x.xxxx
HOLD2=y.yyy
HOLD3=zzz
The third line is the exposure and is a number between 0 and 1000 (I don't know if that's inclusive or not). I don't know what the number represents, but I believe it to be milliseconds (lower is a lower exposure time).

To force the exposure low:
  1. Set the exposure to Hold Current.
  2. Go to the script editor (I forget where it is right now, but it's near the same place you create backups).
  3. Find /dynamic/image.conf
  4. Set HOLD3 to the desired value (150 was a good value for me).
  5. Save the file.
  6. Power cycle the camera.

This doesn't work every time, and seems kind of random, but once it works, it will stay between power cycles. Once you get it working I recommend backing up the settings and not changing the exposure programmatically.

With this change I was able to get tracking working at 8fps even while wildly flailing the camera around .

Last edited by Bigcheese : 07-02-2010 at 21:59. Reason: fixed title