Fantastic feedback. Thanks.
RG-I get your point(s) and agree. There's a fine line. With over thirty years in biomedical research, I have pretty thick skin, but I have no formal training in art so I value these discussions enormously. BTW, I used the levels tool to add a full on black in some small areas; I think it does enhance the contrast a bit. I only brought the left slider up to 10. I also clipped the highlights down to 245. Overall, a subtle enhancement of contrast.
Slobodan-I thought about your comments all night! And I got to thinking about whether I had pushed up the blue and cyan saturation and sure enough, I had so I set both to zero. That shows in image 3 and includes the blacks and highlights adjustments above. This morning I saw your comment re the hue slider, which I have never used until now, so thanks for the thought! In image 4, I pushed the cyan hue slider to +10. I wouldn't call the difference subtle compared to the first image (I think most of the cyan cast is gone in 4), but I also didn't have that sense of "graying out" the sky. So I felt that this better reflected the scene as I remember it. I would never have thought to try the hue slider had you not mentioned it, so thanks! BTW, I've seen the green river and that's a lovely shot of Chicago.
William-I will keep that "trick" in mind. Like the hue slider, I often do not touch the temperature control and let the camera handle white balance.
Erik-Thanks. I was cropping out the homes of Sedona, but I often crop thusly, I guess 'cause I like an upward drawing interest, which the sky does for me.
Chrisc-I don't think I understand what you are saying from a "how to" point of view. I agree that the original sky needed some structural enhancement. If you would, please elaborate.
RG-I will get back to your question in a separate post.
All-Thanks so much for this discussion