My Own Encounter With The Grey Man by Mountaineer

For those who haven't read my first story, the Grey Man is the apparition of a man wearing all grey, specifically trousers, a wide-brim hat, and a waistcoat. He has been seen by both my mother and my father, and we like to believe that he is a former owner of our farm who checks in periodically to see how we are treating his land. Now, I think I might have had my own encounter with him.

November 2nd, at around 7 am, I woke up and sat up in my bed. I looked out the widow, and, for a brief second, saw a man standing in the soybean field outside my house. The soybean field lies across the front yard and our driveway. I would estimate that the Grey Man was standing about 50-75 yards from my bedroom window. The figure I saw met the descriptions given by my mom and dad, with the man wearing grey. In a second, the man was gone. After sitting and blinking my eyes in a stupor for a few moments, I lay back down and sat up again in the same way, wondering if what I saw could have been explained by a trick of the old glass in the window and the early morning light. I did not see the apparition again.

The field is perfect deer habitat, being surrounded by a mix of forest and thick brush. So, my first thought after I determined that it couldn't have been a trick of the light was that I had seen a deer. After some more thought, I ruled that out too. I have seen deer in the same field before, but they were always in groups, I have never seen a lone one. Furthermore, deer are brown, not grey, although with the lighting conditions the two colours could have been confused. Finally, a deer would not have been scared off by me sitting up in bed in my second story bedroom, 50-75 yards from where he was. And even if he had, I would have seen him bounding across the field and towards the woods; he wouldn't have vanished into thin air.
Here are some environmental conditions for anyone that might be interested:

The sun was not over the trees yet, there was just the soft light of dawn. There were no clouds in the sky, though we have recently had a large rain. Finally, we had our first frost several days ago.

I would like to hear what explanations everyone has to offer. Thanks for reading!