I did lower the EV on the camera to underexpose the images in order to get more I could out of the sky.
In post processing I did import the image in Adobe LightRoom and used a custom made setting to convert the RAW file. My camera profile is set on Neutral in order to be able to work the colours better in the post processing.
I used LR to straight the horizon and apply the camera lens correction to avoid image distortion.
From there I did work with Photoshop to clean the image and Nik Software suite .. in this case I reduced the image noise using Dfine and then EFEX Pro to warm the image with colour cast removal. After that I did apply the detail extractor to get more details out of the darker areas.
In the end I did apply the darken/lighten center filter to focus on the little shed on the other side of the pond and some sharpen filter.
If you have any question feel free to ask.