It is possible to filter Slooh 500 list in a few ways.
First filter is altitude where you decide how high the target need to be during the night to be shown in the list.
Then it is possible to filter by time. If there is for example only a specific time slot available the time filter can use used to show what other filter conditions are met at that specific time.
With a moon filter it is possible to show only those targets that have at least the given distance from the moon. If the moon is up it can be useful for example to pick only targets that are at least 90 degrees from the moon.
Filtering points are calculated at midnight and then two and four hours before and after midnight. So in some cases it is possible that a target is not listed if it will match the filter only between those calculated points.