This is a source image. We want to create more separation from the background.
Applying a vignette leaves us with an image that darkens the edges and corners, but does so in a manner that creates a discernable rimming / area where the darkening begins even though the selection was well feathered before creating the vignette.
In this case, a better approach is to apply an adjustment layer and set the Blend Mode to Multiply. I’m using a Levels adjustment but any will do. No changes are made to the adjustment. We only want the multiply blend mode effect. By itself, this will darken the entire image too much. Dial the opacity back to the point where the background looks “naturally” dark. In this case I have pulled the opacity down to 27%. Then use the layer mask to eliminate the darkening in the areas where it is not desirable.
Here is a look at the mask. Note that it isn’t refined. My process is to use a brush set to 100% opacity but a very low Flow rate (5%) to trace the outline of where the area to be masked out is. I then view the mask [ALT-Click or OPT-Click on the mask to view] and paint inside the lines with a higher flow rate (25-50%) until the masked area has the density I want. Using a very low flow rate means I have enough of an edge that I can see where to paint without the need to be very exact in hitting all of the edges perfectly.
Once the darkening is done, we add a blank layer set to Overlay and Paint on it with white to Dodge (Lighten) the areas of the subject and story we wish to emphasize. Here again, we paint with the opacity set to 100% and the Flow rate set to a very low number (2-5%). We use multiple strokes to gradually build up the lightening to the level desired. Doing it this way allows us to vary the extent of the lightening in different areas and to just use CTRL-Z or CMD-Z to undo one or more strokes if we overdo it in an area. I prefer Overly for dodging as it adds a bit more contrast. I use Soft Light for burning in because it adds less contrast. Many tutorials suggest doing this on a layer filled with 50% gray as the Overlay and Soft Light blend modes are blind to 50% gray, but there is no need to add an additional full pixel layer to the size of your file. I don’t use the Dodge and Burn tools for this type of work because I want highlights, middle tones, and shadows all adjusted by the same amount in any given area. There will be other times when I am only interested in darkening a shadow or lightening a highlight where I will use those tools.