Easy way to determine hours of dust-to-dawn hours between dates for a given latitude?

[Electric-Light]

I am wondering if there is an app or a site that can let you enter latitude, start date and end date and provide cumulative dusk-to-dawn hour.

I would like to have an easier way to calculate cumulative dusk-to-dawn hours between dates to help with auditing a group of installed fixtures for conformance with LED degradation allowance specification at the given burning hour.

 

[GoldDigger]

I would be concerned that the dusk to dawn time based solely on sunset/sunrise will not necessarily accurately represent the on time of the lighting.
On the other hand a member here produces photocell drop-in replacements that use GPS and astronomical data to control on/off times.
That is totally predictable and I would not be surprised if his company either has or could easily provide the kind of application you are looking for.

Sent from my XT1585 using Tapatalk

 

[kwired]

I bet whatever you may find doesn't factor in the 2-1/2 minutes of solar eclipse some will experience next month

 

[ggunn]

I am wondering if there is an app or a site that can let you enter latitude, start date and end date and provide cumulative dusk-to-dawn hour.

I would like to have an easier way to calculate cumulative dusk-to-dawn hours between dates to help with auditing a group of installed fixtures for conformance with LED degradation allowance specification at the given burning hour.

This would likely do what you want:
http://solardat.uoregon.edu/SunChartProgram.html


Oh, you said cumulative. Never mind.

 

[Ingenieur]

This would likely do what you want:
http://solardat.uoregon.edu/SunChartProgram.html


Oh, you said cumulative. Never mind.

under software tools there is an excel version
he may be able to do something with it

 

[Ingenieur]

This calculates hrs daylight per day for a year
http://aa.usno.navy.mil/data/docs/Dur_OneYear.php

table is a matrix of days and months
exportable into excel
can then be converted to hrs of night (24-daylight hrs) and manipulated for a given date range
typ table
http://aa.usno.navy.mil/cgi-bin/aa_durtablew.pl?form=1&year=2017&task=-1&state=DC&place=

 

[Little Bill]

Some of the Intermatic Timers that are astronomical have data on that. Some come on a spec/instruction sheet and also have it in the timer program. You put in the info for your area and it sets the timer accordingly for D>D.

You might look on their website and get a chart. Probably have to do some math though for the cumulative part.

 

[junkhound]

search for insolation tables (yes correct spelling) on solar sites - you will get everything you need, including dark cloudy day data, etc.