If you are a photographer, I am bound to defer to your knowledge, but I still don't have much doubt that if a light generates sufficent brightness, or is distant enough, its edges will appear to blur.
You are still wrong. As wrong as can be. The blurred out-of-focus image is a feature of the optics used and will assume the shape of the aperture gate. It's dark here, but there's nothing brighter and farther away than the sun and you can take an out-of-focus photo of the sun and as long as it's not over-exposed, it won't have blurry edges. Trust me.
But you are straying from the article. The Colonel has a photo of the lights he saw and they strongly resemble the out-of-focus photo of streetlights I posted above. Even in his picture there is no appreciable difference between the "UFO" and the lights of the radio tower he admits is on the right. His photo proves nothing and is useless as a record of what he saw since it is so out-of-focus.