I was asked to capture a wedding proposal at a local winery, Retzlaff Vineyards, a while back. The groom to be was pretty calm as we did a site check the day before. The site check allowed us to determine the best spots for photography as the afternoon light might not have been cooperative on the big day.
Settling on getting his girlfriend positioned on the east end of the picnic area was the plan. This was in order to shoot in full shade and not have too many bright highlights to ruin the images.
Not wanting to blow the surprise I was working to not be too suspicious. I used my Nikon D4 and my 600 f/4 telephoto lens to capture the action without getting too close. I pressed into service my wife playing with our dog on the lawn area as my fake subjects while I was using such conspicuous equipment. While the lens is mostly used for wildlife, it does allow me to capture images of surprise engagements as well.
A few images after with shorter lenses made for an impromptu engagement session.