Changing the colour of a background

[Snappers]

Hi all,
I'm sure this has been covered before but I can't seem to find it.
Could someone tell me how to change the colour of a background in a photo using Photoshop.

http://www.proudphotography.com/forum/gallery/files/7/4/8/butterfly_apple_orig.jpg

Here above is the original photo and I want to remove the blue cloth background and replace it with black. I tried by creating a new layer with a black background and then using the erase tool to make the apple come through the black but my hand is not that steady and it did not look brilliant as you can see.

http://www.proudphotography.com/forum/gallery/files/7/4/8/butterfly_apple.jpg

So what could I do differently to make it better. I really want this apple to POP out of the pic.

[dkippen]

Andy - I would try using the magnetic lasso to select the apple, then copy to a new layer filled with black. I'm sure there's a more refined way, but I'm at work and going off memory.

[jerryph]

The lasso tool is what I would use too. Its a lot faster as well!

[gocamels]

I like the Quick Select tool personally. My hand isn't steady enough to use the lasso. The color difference is so big here, you can probably use the Magic Wand and just make small adjustments with another tool.

Your other option is to copy the layer and darken the top, then add a layer mask and paint out the parts you don't want darkened. It just depends how much darkening you want.