This is a 6 minute video by “Waves Audio”, focused on making MIDI brass samples sound realistic in your compositions.The most important thing to learn from this view is that, unlike string players who can play one long overlapping sustained note after another, brass players can’t do that. They need to breathe. Ensure your long notes aren’t too long and make them stop long enough for a brass player to take a breath for the next note. Using sufficient reverb on your brass samples, helps blend the long notes together in a more realistic way. Brass players sit at the back of the orchestra so in a live setting, they will experience a lot of reverb, second only to the percussion section.
The video also discusses using a couple of effects, for analog warmth and some EQ, but what I also found interesting about this video is the supporting string tracks. Notice the strings are divided up to play an ostinato pattern, some accents on the ostinato pattern and some longer held notes. A fine example of making good use of your string section instead of having every one playing the same thing or half your string section sitting silent while the 1st violins do all the work.