Hawaii don't follow daylight saving time, like New York, thus the difference is 6 hours in winter and 5 in summer. Just to be sure:
*Starting time at UTC-10: 12:01 am September 1 in Hawaii = 6:01 am in NYC = 2012-09-01T10:00 UTC
*Closing time at UTC-10: 12:01 am October 1 in Hawaii = 6:01 am in NYC = 2012-10-01T10:00 UTC
> Date: Sun, 26 Aug 2012 15:35:46 +0200
> From: platonides@gmail.com
> To: wikilovesmonuments@lists.wikimedia.org
> Subject: Re: [Wiki Loves Monuments] time, placement list
>
> On 26/08/12 02:39, Peter Ekman wrote:
> > As far as the time the contest should run in the US, please make it
> > 12:01 am September 1 to 12:01 am October 1 Hawaiian Time, which is
> > 5:01 am Sept 1 to 5:01 am October 1 New York Time. (The :01 is there
> > because 12:00 is considered to be ambiguous for the date in the US -
> > all our laws take effect at 12:01!)
>
> 12:01 am. Hawaian time does not seem to be the same as 05:01 am New York
> Time:
>
> TZ=UTC date --date='TZ="Pacific/Honolulu" 12:01 am September 1'
> Sat Sep 1 10:01:00 UTC 2012
>
> TZ=UTC date --date='TZ="America/New_York" 05:01 am September 1'
> Sat Sep 1 09:01:00 UTC 2012
>
>
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