the sample picture, depth of focus is large, and so all the details
are sharp. We'd like to emphasize the monument in the foreground by
blurring the background.
the tools palette, change to Quick Mask mode by clicking the
icon marked with a red circle. Nothing visible happens, but in this
mode, you can use a properly configured brush to mask out the areas
you want to leave sharp. Later changes will not affect the masked areas.Change
to the Brush tool (press B), select a mid-sized brush
(we have used a 45-pixel one), and carefully cover the areas
you want to leave unchanged. By default, covered areas display with
a red veil. This won't affect the picture directly, only signals Photoshop
which areas are not to be touched.
the mid-sized brush, select a smaller one with a sharp edge, and cover
the sensitive areas and the edges of the shape more carefully. Keep
in mind that you should only cover the areas that you want to stay sharp.
Paint the boundaries between the sharp and blurred areas with a sharp-edged
brush! This requires a bit of dexterity and experience. In this example,
we have used a 9-pixel sharp-edged brush, and a 5-pixel
one for even smaller details. For more accurate work, enlarge the details
of the photo on the Navigator palette. If you accidentally cover something
you shouldn't, press E to change to the eraser tool, and
use a similar-sized eraser to undo the unwanted mask, and restart covering
the area that needs it.
finishing the mask, click the icon to the left of Quick Mask,
or press Q to change back to Normal mode. The red veil
disappears, and the uncovered areas become selected. Our next steps
will only affect these areas.Click Filter/Blur/Gaussian Blur
to blur the background. On the dialog, set a blur radius of 1
to 2 for wide-angle pictures (that is, if the picture contains a
larger area). If the photo was taken with a teleobjective or contains
only a smaller object or theme, you can use a larger blur. If you set
a too large blur for a wide-angle photo, the result will look unnatural.
You may do so if you wish but in such cases, a smaller blur produces
more plausible results. We have used a radius value of 2,
which is perhaps already on the borderline, but we wanted to underline
applying the Blur effect, press Ctrl+D to remove the selection,
and finally, save the image.
blur II. in Photoshop
effect in Photoshop