If your 21:30 is in B2, and your 19:30 in D2, the formula =B2-D2 will give
2:00, or use =IF(B2-D2<0,"",B2-D2) if you want the result blank if B2 is
less than D2.
--
David Biddulph

"joe1999" wrote in message
...
Thanks Sandy I'll try that,
what I have is this in columns
16:30 (time out)
21:30 (time in)
5:00 (total time)

now if say sunset is at 1930 what want is another column
2:00 (night)

hope that makes more sense.


"Sandy Mann" wrote:

If I understand you correctly and assuming that you have - say - sunset
in
B2 and sunrise in C2 the:

=MOD(C2-B2,1)

will give you the hours of darkness.

--
HTH

Sandy
In Perth, the ancient capital of Scotland
and the crowning place of kings


Replace @mailinator.com with @tiscali.co.uk


"joe1999" wrote in message
...
Hi all,

I have a logbook spreadsheet with hours logged in time format and the
total
calculated in the third column formatted [h],mm, If I specify sunset in
a
time format can I get the night hours in a seperate column?
cheers