Making a softened shape to go underneath a logo or headline text

If you are making a poster with a full-size background image, and you also want to include logo or other prominent item (text-headline), then you may want to soften the background image underneath the logo etc.

The long way of doing this

1. Make a new layer
2. On it, draw a shape that is the size you want to soften
3. Make a gradient overlay affect on the shape: Choose radial gradient in fx settings, and play around with the values to get the look required.
4. To give it a soft edge, use an outer glow affect (Layer panel - right click the layer, Blending options)

Tutorial about adding gradients: http://www.photoshopbuzz.com/shape-transparent-gradient/

The fast way

1. Go to a website like https://www.freevector.com/vector/glow and download something which is close-enough to the shape you want in a vector format (eg .eps or .ai)
2. Open the file in photoshop, resize etc if necessary,
3. If necessary, apply an outer glow effect.