The Ground of seeing and seen is of course really one field.
It is the field of seeing-seen, or even the field of Ground-seeing-seen...!
It is seamless. It is absent of I anywhere. It is simultaneously, and as a whole, subject and object.
And yet, it can be talked about in all of these ways - and many more - when a layer of abstraction in placed on top of it. When various aspects of this field is filtered out and the relationships between these are explored. But this is merely a way of talking about it. As anything expressed, it immediately goes into the realm of the relative, and has no absolute truth to it. It is merely a finger pointing.
The funny thing is that all of this is alive in immediate awareness to all of us. It is only the filter of the temporary belief in the idea of I which (again temporarily) makes it appear differently. The field of seeing-seen temporarily splits itself into I and Other, and our human self then acts as if it is true.