Hello,
Here is a technique I like to use when cropping out images. It's very clean easy to do. Once you master it cropping out images become very easy.
If you have a small Wacom Pen and mouse pad it will make your job easy. They run about $99 but take time to get used to the pen. But it is a great tool!!
Make a copy of your background image. Crtl + J. This will make a copy.
Make a new layer on top of your copy image, make sure you have that new layer selected in you layer pallete.
In your foreground color choose a very hot bright color. I like to use 0R 255G 51B.
After you select your color now select your airbrush tool (J)
Make sure your hardness is +100% and select the brush size that is easy to use. Start small first, trust me.
Now what you want to do is airbrush (I call it masking your subject) around your object. Cover the area you want to drop-out. Make sure to cover all edges. Make small strokes when you are close to your subject, if make a mistake by painting into the image press ctrl + z. I like to be zoomed in when I am doing this. About 200-300% but then again this depends on your resolution. Also when you reduce your image size the edges will get you a sharper. I like to have a high resolution image or a large size image.
Ok, once you covered the area you want to drop out(hint: I use a small brush around the subject that have tight coners. Once I have the image out lined I then increase the brush size) Now press Ctrl+left mouse button on the lime green layer (note make sure you click on the image icon not the word example like Layer 1 that has a diffrent function).
You should see a marquee or marching ants around the lime Green mask. Now go to your menu > Feather and enter 1 pixel click ok.
Now select your copy layer of your image in the layer pallete. This is important Then hit delete. Now turn off the view for the Lime green layers and the background image.
So you now cropped out your image. The feather makes your edges softer and does not look so hard. You can now place any background color.
Hint: I sometimes make a new layer, place it under the new cropped image and fill that with lime green and zoom in to view the edges of my crop image. If you don't like it. Delete it and start all over. That is why I had you make a copy of your orignal image. Alway do this if you are going to do any editing to a image. Anything!!! Trust me I have made those mistakes 
If you made a mistake you still have the original.
I hope this helps. I use this method for fine jewelry. I prefer it better than the masking tool or magnetic Lasso.
I hope this helps. If need more help let me know.
David
MikeRenardo wrote:
I run a silk businness, and I recently purchased a Canon Powershot G3 to take pictures of silk ties for my website. I bought a photoflood lighting kit. Two lights, 250 watts each...
All I want to do is take pictures of my ties, nothing fancy, no creative photography. The only effect I want to create is the "white background." I don't know how else to put it, I'm rather new to this.
I'm sure every single one of you have seen pictures of a product with a completely white background. Right now, I'm shooting my pictures with a white display board as the backgrond. When the pictures come out, the tie looks excellent, but the background is a salmon type color. I want a white background because it will look better on my website.
Is there a special technique I can do with the camera? Or do I need to purchase a special type of paper/material for my background? Are my lights ok? (They reproduce the daylight spectrum)
Are there any other techniques that may be of use to me?
Thank you so much for your help.