Andres Brilliante HDRI Method: How To Fake HDRI Photography in Photoshop
I. Begin

Open Document
II. Duplicate Layer

Right click “Background”
Select “Duplicate Layer”
Press
OK
III. Invert Top Layer

To
invert copied layer, press CTRL+I
IV. Restore Hue


To adjust hue, press CTRL+U
Set “Hue” to +180
Press OK
V. Blur Top Layer


To blur top layer, select Filter > Blur > Gaussian Blur
Select roughly 40 (Season to taste)
VI. Set Layer Blending Mode

1. Set layer blending mode for “Background Copy” layer to “Soft Light”
2. Experiment with opacity to refine the effect.