The Analogue Input tab contains information about how the data is being sampled and also gives you control over the Start Delay, which needs to be adjusted between scan speeds during bidirectional scanning.
|A||ADSamples.per.frame||The number of samples being acquired per frame. SciScan always samples at the fastest possible rate, with one sample being taken for every tick of the sample clock. The number of samples is a function of the number of pixels, the dwell time and the fill fraction.|
|B||Sample.Clock||The sampling speed of the data acquisition card. 5MHz in the case of the PCI-6110|
|C||Pixel.dwell.time.in.ticks||The number of ticks, and therefore samples, taken per pixel at the currently applied pixel dwell time.|
|D||autocorrect.start.delay||Uses image features to attempt to find the most appropriate start delay setting. See below for more information.|
|E||Start.delay||In Bi-Directional scanning the acquisition of every second line becomes shifted relative to the one before it depending on the scan parameters. Start delay can be used to correct for this shift. Set using either the sliding scale or start delay box.|
Below is an image demonstrating an incorrectly set start.delay. “Comb” artifacts or a “double image” appear depending on how far out the start delay setting is. Adjust the Start.Delay setting to correct for the image issues.
Autocorrect Start Delay
The Autocorrect.start.delay feature uses image features to try and find the best possible setting for the start.delay. As it relies on the recorded image to make its adjustment a moving average of 10 frames must be applied before SciScan will attempt to line up the forward and reverse scan images. Once ready, press the green button and allow SciScan to complete its calculations before continuing.
Start Delay Lookup Table
To avoid having to adjust the start delay every time you change a parameter; SciScan creates a look-up-table using the startdelayLUT_coMD.vi plugin. SciScan keeps track of the last used start-delay setting for a given combination of scan parameters (zoom, resolution, ect..) and saves it for the next time you use these settings. If you are using a set of parameters for the first time you will need to correctly set the start delay by either adjusting the start delay slider, or by using the Autocorrect feature as described above. Once it has been correctly set once, you should be able to switch back to these settings and the start delay should be remembered.
Posthoc Start Delay Correction
If tan image has been recorded with the incorrect start delay, this can be corrected posthoc in the RAW file using the posthoc start delay correction.vi. For information on how to correct the VI see the Posthoc Start Delay Correction page.