I can only tell you my local times. It differs by location. Please check the linked-to websites for your own local times, by filling in your own zip code.
For Kew Gardens Hills, in Queens:
|Tzeit Hakochovim (nightfall)|
They typically add 3 minutes to R' Tukaccinsky's time, which is how they get to 8:35 from Chabad's 8:32. As they write,
* 3 minutes have been added to compensate for the fact that the שקיעה times (for ירושלים) printed in ר' טוקצינסקי-'s luach, are 2 to 3 minutes later than the times for "sea level שקיעה". Definitions provided by otherPoskim may also be subject to a similar translating.There are other times listed at the website for nightfall, as well? So, which should you follow? This is an area where you should consult your local Orthodox rabbi, or find out your own family's shitta, at least once, so that you know which to follow.