Very nice photo! We reconstructed a barn 30 years ago from new poles and old barn boards, looks very similar to yours. I am wanting to keep the red/not-red look while protecting the siding and have tried various applications. Last try was to overcoat everything with a neutral oil, which worked for the most part. But, we have some newer wood on one side of the barn which I would really like to try to age, if at all possible, preferably with a reddish tinge. Any thoughts?