mshchem
Subscriber
I'm not sure I understand what you're getting at. I did use Sunny 16 rules for exposure, in the one I posted I had the aperture open wider than f/16 to capture shadow detail. Probably at least one or two stops. So I don't see how this would cause the sky to be darker in any way apart from, like someone has mentioned, the sky actually being darker in reality than it feels when you're there.
All I was, my fault for not being more clear, was suggesting, Is rather than throwing in another variable, my recommendation would be to try to minimize the unknowns here. Try reshooting, with the sun at your back, see if you don't get nice snappy contrast. Normal looking negatives. Fresh developer and fixer too.