Update install.sh: Warn in no RPi camera command was found

install.sh

@@ -302,10 +302,11 @@ CT=()			# Camera Type array - what to display in whiptail
 
 get_connected_cameras()
 {
-	local CMD  CC  MSG   NUM_RPI=0   NUM_ZWO=0
+	local CMD   CMD_RET  CC  MSG   NUM_RPI=0   NUM_ZWO=0
 
 	# true == ignore errors.  ${CMD} will be "" if no command found.
 	CMD="$( determineCommandToUse "false" "" "true" 2> /dev/null )"
+	CMD_RET=$?		# return of 2 means no command was found
 	setup_rpi_supported_cameras "${CMD}"		# Will create full file is CMD == ""
 
 	# RPi format:	RPi \t camera_number \t camera_sensor [\t optional_other_stuff]
@@ -358,7 +359,12 @@ get_connected_cameras()
 		whiptail --title "${TITLE}" --msgbox "${MSG}" 12 "${WT_WIDTH}" 3>&1 1>&2 2>&3
 
 		MSG="No connected cameras were detected."
-		display_msg --log error "${MSG}"
+		local MSG2=""
+		if [[ ${CMD_RET} -eq 2 ]]; then
+			MSG2="No command to take RPi images was found"
+			MSG2+=" - make sure 'libcamera-apps' is installed if you have an RPi camera."
+		fi
+		display_msg --log error "${MSG}" "${MSG2}"
 		exit_installation 1 "${STATUS_NO_CAMERA}" ""
 	fi