たとたん vs たところ — both about 'right after X happened'?

Question

ドアを開けたとたん、猫が飛び出した vs 駅に着いたところ、電車はもう出た後だった. Trying to work out if たとたん emphasizes a much shorter/more sudden gap than たところ, which feels more like 'as it turned out'.

Accepted Answer

Good read. たとたん = an almost instantaneous, often surprising/dramatic result the SECOND the first action finishes (door opens, cat instantly bolts) — very tight timing, usually something abrupt. たところ is closer to 'when I did X, [as a result] I found/discovered Y' — it frames the second clause as a discovery you stumbled onto, without the same emphasis on split-second timing. たところ can have more gap between the two events than たとたん would ever allow.