Sigma LBA-714PC, LBA-710 Frame Summing, Frame Average, Gain Correction, Reference Subtraction

•Ultracal processing cannot be a part of a post processing operation.

Gamma Correction is also a type of processing. Gamma Correction is controlled from the Camera dialog box, as it relates to a specific camera’s characteristics. Gamma correction can be part of a post processing operation.

3.2.4.6Frame Summing

Click on this item if you want the LBA to sum frames. Specify the Number of Frames that you want to sum into each frame placed in the frame buffer. Frames are always summed in the order that they are input. Frame summing can be used to increase the apparent size of low-level signals. Fixed pattern noise will unfortunately grow linearly with each summed frame, but temporal noise will increase at approximately the square root of the number of frames summed, thus the resulting signal to noise ratio will be improved.

3.2.4.7Frame Average

Check on this item if you want the LBA to average frames. Specify the Number of Frames that you want to average into each frame placed in the frame buffer. Frames are always averaged in the order that they are input. Frame averaging will improve the signal to noise ratio by approximately the square root of the number of frames averaged.

Note: If the frame that you are averaging has poor pointing stability, then the reliability of the computed results of an averaged frame may not be very good.

3.2.4.8Gain Correction

Check on this item if you want to apply Gain Correction. You must have Generated or Loaded a gain correction table, before you can apply gain correction processing to newly acquired or post processed frames of data. See 3.1.8 Generate Gain, for further details.

3.2.4.9Reference Subtraction

Check on this item if you want to subtract the reference frame from newly acquired or post processed frames of data. The reference frame is location 0 (zero) in the frame buffer. This location is always reserved for the reference frame. The content of frame 0 will be subtracted from the results of all other processing operations. Associated with creating and saving a reference frame is the Set Reference Source edit control (shown above), and the Set

Reference action item in the Files menu, and the set reference toolbar button. See Set Reference for further details.

The Set Reference Source edit control allows you to select what type of data will be loaded into the reference frame.

Using this feature with the four-camera option will cause the reference frame to be subtracted from the input of each camera. It does not discriminate between camera selections.

Operator’s Manual	65	LBA-PC
Doc. No. 10654-001, Rev 4.10