iwlist vs tethereal in capturing 802.11 wifi ESSID and data

[powah]

I found that iwlist will capture 802.11 wifi ESSID and data rates more often than tethereal. i.e. Sometimes tethereal does not capture ESSID and data rates at all.
Do people had similar results?


The commands I had used are:
iwconfig ath0 channel 6
or
iwconfig ath0 channel 11
or
iwconfig ath0 channel 36

iwconfig ath0 mode Managed
iwlist ath0 scan



iwconfig ath0 mode monitor
tethereal -i ath0 -c 100 -w /tmp/sniff.capture
tethereal -V -r /tmp/sniff.capture > /tmp/sniff.capture.txt