The Ophioninae includes the large orange-brown species that are commonly found at night flying around lights. 
All nocturnally active ichneumonids are pale, slender with long antennae and legs. 
There are quite a few of these large orange Ichneumon wasp species in The Netherlands and they are very difficult to tell apart.
For instance, there are several species within the genus Ophion and the genus Netelia.
Netelia species are distinguishable by the small cell near the pterostigma (at the base of the two veins leading to the tip of the forewings) called the areolet which is triangular in shape. 
That cell is not present in Ophioninae (like on the photos). 

The photos likely show Ophion luteus, which is common and usually seen in April and July, August and September.
In addition, it is known to be attracted by light (like my moth trap).

Caught in my self made moth trap.

First 4 photos: In my yard, Hilversum, The Netherlands, 16 August 2018
Last photo: In my yard, Hilversum, The Netherlands, 23 April 2020