Time range from timestamp

If anyone could help me with this would be great! :grinning:

Question 1:
There’s a timestamp in every log.
I need to make a graph that shows the total time of logs that are later then 08:00
So if theres a log with timestamp 14-11-2018, 08:50:03
I need to know the time it has passed 8 a clock, so: 50.03
Then I would like to know the total time for the past 30 days, is this possible in Grafana?

Question 2:
With a single timestamp, is it possible to make a graph with just the date on the x-axis
and the time on the y-axis? As there’s only one timestamp log each day.

Thanks alot