PDA

View Full Version : Accurate masks using CorelDraw


deddard
August 18th, 2008, 11:00 AM
After taking pictures of cars at motor shows, I neeed to mask out the backgrounds, but the tools within Photoshop Elements weren't always up to it - highlights on the car, variations in colour etc prevented the usual selection tools from creating nice lines for me to then use as a mask.

THe solution was simple - ensure you are working at 300DPI, and copy the image in a supported format (TIFF, JPEG etc) into CorelDraw, and then manually trace around the required part using the vector tools (bezier etc).

Then delete the original picture in CorelDraw, leaving just the vector image.
Fill the image with pure black, and then export the image as a TIFF or JPEG ensuring the resolution stays at 300DPI.

Now open the saved file with Photoshop ELements, and copy it into a new layer in the picture you wish to mask, select the mask with the magic wand, then switch to the layer which needs editing, and do whatever is necessary (deleting, colour balance, effects etc.)

Diana
August 18th, 2008, 01:22 PM
If you're doing it manually, you can do the same thing in Elements without all the extra steps. I do this all the time.

Zoom way in on your subject, say 200-300%. Grab the Polygonal Lasso tool and click in short intervals all around the subject. Pressing the Spacebar turns the Lasso into the Hand tool so you can drag to new areas of the image as needed. When you arrive back around to the starting point, double-click to complete the selection.

By pressing Ctrl-J you can put the subject on its own layer and then add a new background in a layer beneath it.

Or, once the subject is selected, Ctrl-C to copy, then open your background image and Ctrl-V to paste the subject onto the new background.

You can use the Blur tool (in the same set with the Smudge & Sharpen tools) to go around the edges of the subject to help blend it in with your new background.

Here's one of my images where I moved the subject to a new background:

http://www.pixentral.com/hosted/1UTWFjoumc00lDATya9BuycuKo55_thumb.jpg (http://www.pixentral.com/show.php?picture=1UTWFjoumc00lDATya9BuycuKo55)

Diana

deddard
August 19th, 2008, 09:42 AM
HI Yes, the lasso tool can do this, (I also use this technique), but the vector image technique is useful when there are definite lines to follow - you can do things like cars with complete accuracy because of the way vector graphics work. The lasso tool, is great, but adjusting the vector of the curves by editing the nodes isn't something you can do in Photoshop. This is the key thing with vector images - the ability to adjust the nodes with such accuracy. Sometimes you can't see the place where you need to select with the lasso (highlights etc which burn out the edge of a hard object), which is where the bezier tool comes in - just take the node beyond the highlight and adjust the curve to create a smooth line (OK, you need to know where the line is!)