So we are using a vray camera to match our model of an existing parking lot into a photo of the parking lot. We shot in RAW so we know it was taken at 18mm but on a crop-frame sensor so we should use a focal length of 27.46 to be exact. Well, with these settings, our match isn't even close. It wasn't until I put the focal length at 42mm that everything matches perfectly (camera location, light poles, parking islands, etc).
So this makes no sense to me. How can the focal length of the vray cam be so far off of the actual photo? The only thing that I can think of is that the photo was taken in vertical orientation. My vray cam isn't vertical orientated. I'm using the output resolution to make the frame vertical. Could I be correct that my vray cam is essentially having to zoom in on the vertical orientated frame forcing the focal length to be larger? Has anyone had to deal with this issue?
Thanks for any incite!
Jared