using a fixed crop border for spots

sensospot_grid/parameters.py

@@ -59,10 +59,13 @@ def spot_parameters_from_xml(tree, array_parameters):
     rx = array_parameters.dist_x
     ry = array_parameters.dist_y
 
-    # ROI is strangely named in params file, it's actually the outside crop
-    reg = tree.find("Registration").find("Settings")
-    cx = _to_micro_meters(reg.attrib["ROIMarginWidth"])
-    cy = _to_micro_meters(reg.attrib["ROIMarginHeight"])
+    # before, the ROIMarginWidth and ROIMarginHeight settings from the array 
+    # analysis was used. But this seems to be more or less independend of the
+    # spot offset. Therfore we crop 100µm more than the spot offset. 
+    # for future reference, how to access the node:
+    # reg = tree.find("Registration").find("Settings")
+    cx = rx + 100
+    cy = ry + 100
 
     return SpotParameters(rs, rb, rx, ry, cx, cy)