Reducing the video resolution (the number of pixels captured per line and column) allows capturing more video frames in a given size of frame buffer memory. From the PIXCI® Image Viewer, click:
Click:Capture Adjustments Res(olution)
and draw the new desired area to be captured by left clicking and dragging over the displayed image. Click:Set Video Window
to accept the new capture resolution. Note: Changing the capture resolution will destroy any images previously captured in the frame buffers!OK
The
shows the number of frame buffers available with the current selections.Capt(ure) Frame Buffers
The selections under the PIXCI® Image Viewer:
are automatically saved when the PIXCI® frame grabber is closed, and/or XCAP is exited. When the PIXCI® frame grabber is next opened, clicking (from the XCAP Main Window):Adjustments
Choose:PIXCI® PIXCI® Open/Close Camera & Format
to use the previous video setup, or choose:Open w. last used Video Setup
to start afresh with the default video format and resolution.Open w. default Video Setup
XCAP integrates controls for both the PIXCI® frame grabber and the SILICON VIDEO® WGA camera within the Capture & Adjust window. The left side of the Capture & Adjust window contains controls for the PIXCI® frame grabber. The right side of the Capture & Adjust window provides camera specific controls.
The Analog Gain allows adjusting the camera's analog gain. Increased gain allows capturing dark scenes, but at the expense of decreased image quality (increased random noise); Whenever possible, increase illumination or increase exposure instead of increasing gain. The Digital Gain allows adjusting the camera's post A-D digital gain; values lower than 0 dB are typically useful only for special applications.
The Exposure allows adjusting the camera's exposure (shutter) period. When using AC powered lighting, an Exposure which is a multiple of half of the power line's period (i.e. 16.6/2 msec. in the U.S. and other locations using 60 Hz, 20.0/2 msec. in Europe and other locations using 50 Hz) is suggested to prevent varying image brightness due to the illumination's cyclical change of brightness. Selecting Exp. Mult. of 1/50 or Exp. Mult. of 1/60 automatically forces the Exposure to a multiple of the corresponding period.
The AOI Left, AOI Width, AOI Top, and AOI Height allow selecting an area of interest which is read-out and captured. Capturing fewer columns or fewer lines decreases the image size; capturing fewer lines also allows a faster frame rate. If Center Aoi L(eft)-R(ight) or Center Aoi T(op)-B(ottom) is selected, the AOI Left or AOI Top, respectively, is automatically adjusted so as to center the capture AOI, the AOI Width or AOI Height, within the camera's field of view.
The Subsampling allows selecting subsampling (decimation) of the AOI by a factor of ×2, ×4, ×8, ×16, ×32, or ×64 vertically, producing an image of smaller size and lower resolution, and allows a faster frame rate. The Binning allows selecting binning by a factor of ×2 horizontally or ×2 vertically and horizontally, averaging pixels in each group rather than decimation, producing an image of smaller size, lower resolution, and lower noise; the allowable frame rates are unaffected. The Subsampling and Binning features are mutually exclusive.
The Pixel Clock allows specifying the pixel clock rate. A faster pixel clock increases the allowable frame rate, but with reduced image quality (increased fixed pattern noise); a slower pixel clock increases the allowable exposure periods for longer integration and greater sensitivity.
The Video Mode allows selecting Free-Run or Controlled frame mode. In Free-Run mode the camera exposure and read-out is free-running; continuously exposing and sending frames to the frame grabber at a constant frame rate without need of a trigger. In Controlled mode the Controlled Frame Rate, Continuous, and Single Shot provide frame rate and triggering control through the PIXCI® SI1, SI2, or SI4 frame grabber.
The Strobe Mode allows enabling an output strobe to synchronize a flash or other external device to the camera's exposure.
For most common conditions:Capture Adjustments Color (or Clr)
Cover the camera's lens and click:Customize
Finally point the camera at a white target (but preferably not a target using fluorescent brighteners) and click:Black Balance
White Balance
The AEC Maximum, AEC Minimum, AGC Analog Gain Min, AEC/AGC Target Brightness AEC/AGC Rate, and other parameters limits the maximum exposure set by AEC (and thus blur of moving objects), sets the rate at which the AEC and/or AGC attempts to maintain a desired target brightness, and otherwise allow ''tuning'' the response of AEC and AGC. Only using gain adjustments avoids increased blur due to motion of th camera or subject as exposure is increased. Only using exposure adjustments avoids increased pixel noise at high gain settings.