Auto-Fire
An auto-fire is described as an unintentional capture of an "image" without exposing the sensor to sufficient radiation. This issue generally presents itself as a "snowy" or blank image being captured without any exposure being triggered. The type of image that returns can give a quick idea as to the cause of the auto-fire.
- A "snowy" image resembles the static seen from tuning a TV to an empty analog station.
This is generally caused by a connection failure. If the sensor is connected to the PC via any USB extension cables or USB hubs, we would recommend plugging the sensor directly into the PC to avoid any unnecessary failure points (ideally connecting the sensor into the USB ports on the back of the PC, as those USB ports connect directly to the motherboard). - If no exposure is triggered, and a pure, blank white image is returned, the sensor sensitivity is most likely too high. Within the Extension settings is an Option called XVIS Detection Threshold (default 250 mV) which will need increased incrementally and tested to find a point where the sensor does not auto-fire, but still responds to radiation when exposed (as the threshold increases, sensitivity decreases, eventually to a point where the sensor will not recognize any radiation it is being exposed to).
- If the sensor is being exposed and is returning a pure, blank white image, the sensor may not be receiving the necessary power from the USB connection. This is common with laptops and tablets, though does sometimes happen on desktop computers as well. The first recommended step would be to follow the steps outlined in this guide: Disable USB Power Management / Selective Suspension. If that does not solve the issue, the next recommended step would be to use a powered USB hub to connect the sensor to the PC instead of direct connection. Using a powered USB hub guarantees that the sensor receives its electricity directly from the wall outlet, instead of through the Windows managed USB port.
XVIS Detection Threshold - XVCapture/DCV:
- Launch DCV/XVCapture and select Advanced User Tools
- Select Preferences
- By default, the User ID is admin and the Password is AKRON
- Select Imaging Extensions from the left side towards the bottom, click the red caret (>) next to Digital X-ray Image Capture and double-click on the Extension you are using for your E2VII/Hamamatsu.
- Click on the Hardware Settings button found on the left
-
XVIS Detection Threshold can be found on the right under XRay Detection Options
Article Version 1.0 2026.05.07