An example of a particularly interesting out-of-focus pattern across a biological tissue slice. Areas in blue were recognized by the model to be in-focus, whereas areas highlighted in yellow, orange, or red were more out of focus. The gradation in focus here (represented by concentric circles: a red/orange out-of-focus center surrounded by green/cyan mildly out-of-focus, and then a blue in-focus ring) was caused by a hard “stone” in the center that lifted the surrounding biological tissue. |