bug fix

src/main/java/com/elphel/imagej/ims/EventLogger.java

@@ -336,7 +336,7 @@ public class EventLogger {
 		payload[0] = logger_files[file_index_below].getDidPayload(
 				fileinfo_next_below, // , // int file_index,
 				nrec_below);      // int nrec)
-		payload[1] = logger_files[file_index_below].getDidPayload(
+		payload[1] = logger_files[file_index_above].getDidPayload( // was file_index_below
 				fileinfo_next_above, // , // int file_index,
 				nrec_above);      // int nrec)
 		if ((payload[0] == null) || (payload[1] == null)) {