Removing background from a complex image (doodle)

Question

I'm trying to remove the background from this image - http://image.shutterstock.com/z/stock-vector-welcome-back-to-school-seamless-pattern-with-hand-drawn-doodle-elements-vector-illustration-302557214.jpg

I want to remove the grids and make the color 20% lighter. I tried 20% opacity - http://i.imgur.com/BulovTU.png And to remove the background I used magic wand tool but it's not working... as I'm not a professional photoshop user. I want only which background and the doodles.

Please help me on this.

@joojaa Also I've this one(same pic with solid green background) - http://image.shutterstock.com/z/stock-vector-welcome-back-to-school-seamless-pattern-with-hand-drawn-doodle-elements-vector-illustration-302557118.jpg And after editing it on photoshop I got 😭 http://i.imgur.com/8sIfrr5.png

Answer 1

It would be much easier to work with the vector in Illustrator, but if you must work in Photoshop this might help you out a little.

You can use the Select Color Range tool using setting similar to what I have here:

And then fill the selected area with white, and you should get some decent results. This is what I ended up with:

After that, just adjust the color to your liking and you should be set.