If you put the resulting image next to the original photo you will see that after AKVIS Enhancer application the details on the earth, in the sky, on the lorry have become clearer, besides the overall contrast of the picture has improved.
We use the AKVIS Enhancer plugin in this tutorial, but you can take the standalone edition and use the same parameters to achive this result.
Select the Improve Detail mode. The photo will be processed at default parameter values.
Press the button to apply the result of the photo correction and close the plugin window.