The first one does not seem to have the light problem and is nice. Light could be entering the viewfinder or the tube connections so perhaps try covering these possible inlets to reduce the number of culprits. I often get this when I am using the screeen and forget to cover the viewfinder especially in a very well lit situation.
Thank you. I have not had a chance to shoot a shot using your's and Mark's suggestions, but I believe you two are correct.