Background Tutorial
Using the Magnetic Lasso tool in photoshop.
The Magnetic lasso tool work best when their is edge contrast between the subject and the background.
click on the magnetic lasso tool and set the preference's on the top tool bar to width 5px
edge contrast to 25%, Frequency to 57, these setting work best for me but experiment with different
settings. Using the magnetic lasso trace around the subject, when you have connected the selection
go to the quick mask mode (next example)
Click on the quick mask mode button, black foreground color adds to the selection and
white subtracts from the selection. Look at your subject and see if the red mask bleeds in
to your subject.
if the you need to remove the red mask from areas click on the white foreground and use a
brush to remove the mask, likewise if you need to add the mask go to black background color
and add masking to that area.
After you are satisfied click on edit in standard mode and your screen will return to you selection.
Open a new background and use the move tool to drag you subject to the new
background. Your subject will be on a new layer, hold down the control key and click on the
layer with you subject you will have a selection around them. Go the select menu, modify, border
type in 3 pixels, you now have a border around you subject, go to filter blur, Gaussian blur and
move the slider to 2 pixels hit OK. This will soften the edge of you subject and help it blend in
with the background, at 100% magnification look at the area around you subject and use the
eraser tool to remove any artifacts.
Using a mask.
Double click on the background layer to make it layer 0. Use the lasso tool and make a
rough selection around you subject. Go the select menu and click inverse.
Go to the edit menu and click cut.
This is how your screen will look, now go to the layers pallet and click on the mask button (the square
button with a circle in the middle). use a sharp edge brush and and set the background color to black
black removes pixels and white restores pixels. Start removing the remaining area of background,
if you should get to close to your subject just go to white and restore what you removed.
When you feel you have a clean selection drag the mask to the trash can and click apply mask
when the dialog box appears.
Hold down the control key and click on the layer you now have a selection around you subject.
Go to the select menu, modify, border and type in 3 pixels.
Go to the filter menu, blur, Gaussian blur and move the slider to 2 pixels and hit ok.
Now take the move tool and drag your subject into the new background.
At 100% magnifications check to see if their are any artifacts let from your subject and
use the eraser tool to remove them.
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Using the Extract tool in photoshop
Open you image and go to filter extract.
Select the brush tool in extract and check on smart highlighting. This work somewhat like the magnetic lasso tool
follow along the edge of you subject making sure you have no breaks.
Select the paint bucket in the tools pallet on the extract screen and fill the area you used to select you
subject, the area will fill with color, (note if the whole image fills with color you have a break in the
line around your subject, click the paint bucket again and use the eraser to remove the area around your
subject and start over. When you have subject filled with the paint bucket hist ok or preview,
with preview you can touch up the edges after the extract applies.
This is how you image will appear in photoshop, go the select menu and select modify, border, type in
4 pixels hit ok, go to filter menu blur, Gaussian blur move the slider to 2 pixels and apply.
Using these backgrounds are great fun. You may feel that this is time consuming but the more you
do it the faster you will get. I also find that using a solid black background for subjects in lite clothing
or a white background for subjects in dark clothing speeds up the selection. Chroma key backgrounds
also work well.
Click on the link below to see Russell Brown from Adobe do a complicated extraction background switch.
http://www.russellbrown.com/tips_tech.html
Their are many good selection tools on the market, Extensis mask pro, and Corel knockout are very
good, and are plugins for photoshop.
Although this tutorial is for photoshop many photo editing programs work much the
same way.
Get a 30 day trial of maskpro click the link below