Posterising

For this lesson, we learned how to posterize images. This was the image I chose:

 

The first step was to go to Image, Adjustments and then Posterize. I adjust the levels and decided the posterization looked best with 5 levels. This was the result:

 

Next, I went to Image then Mode and Greyscale to change the image to black and white. Then  I went to Image and Mode again but this time selected Bitmap. I changed the frequency to 35 and got this result:

Then I copied this image by going to Select All and then Edit and Copy. I then used Step Back to return to the posterized image with colour. From here, I pasted the greyscale image on top. Then used the layer tools to change the layer's mode to Overly. That had this effect:

Finally I added a new layer and used the gradient tool with a radial gradient to add a blue and yellow gradient to the image. I moved that layer between the Greyscale layer and the original layer and then changed the opacity to 56% This was my final result: