The following parameters are set by Orbit and do now correspond to standard Blast default parameters.
Dust (for nucleotides) or Seg (for protein comparisons) are set to NO.
This means that your query sequence will be used as-is and low complexity regions will not be masked, since removing low complexity regions does not make sense for IP searches.
Search space is fixed to 1750000000000. By fixing the search space, the computed e-value will not be dependent on the database size. Updates after updates, the e-value for a given hit will not change.