Date/Time values from Collector

[Environment_SouthlandGIS_Servi]

Hi, 

We have had a problem when syncing Collector and the data is not showing up in our database.  I have managed to extract the data from the device and can view the data in a sql lite viewer.    I have extracted all the required data except the date and times.  They are showing in a sql lite viewer as e.g 2457800.55.

Does anybody know what time format this is/how to convert it?

I have 2 known records that show the correct time but cannot work out how to convert the rest.

e.g.

I know that:

2457800.549 = 16/02/2017 1:09:56 AM

2457800.55 = 16/02/2017 1:11:40 AM

Any help would be greatly appreciated.

Thanks.

[XanderBakker · Accepted solution]

It appears to be expressed in Julian Days. see for instance this online converter:

Online Conversion - Julian Date Converter 

... or you can use some python implementing existing modules like: julian 0.14 : Python Package Index 

[Environment_SouthlandGIS_Servi]

Perfect.  Thank you very much!!!