After applying the effect:

White Orchid with Simple Dreamy Effect

Original image:

White Orchid

Just follow these simple steps to apply the effect:

Step 1

Open the photograph file that you wish to apply the effect on Adobe Photoshop.

Step 2

Make a copy of the Background Layer by right-clicking on the Background Layer at Layer Palette, select Duplicate Layer… and click OK.

Step 3

Select the Background copy layer on the Layer palette, and apply Gaussian Blur into it by clicking Filter | Blur | Gaussian Blur… Adjust the Radius slider around 4~10 pixel. In my case, I choose 4 pixel radius. Click OK.

Your image will look blurry after applying Gaussian Blur Filter. Don’t worry we’ll fix it in the next step.

Step 4

Change the blending mode (Blending Options) to Screen and you will see the effect like the following.

Step 5 (Optional)

If you don’t like the result, you can change the opacity of the Background copy layer to suit your mood.

Note:
The original image was shot by me using a Sony A300K digital camera with the following exposure settings: focal-length 40mm (60mm eq), 1/40s, f5.6, ISO 100, Spot metering mode, Shade light source, Tripod attached. Exposure program: Manual Mode. The image has been resized from original image size: 3872×2592 px (10.2 Mega Pixels)