Poster Design

This Poster uses the big red font to make it stand out against the white background because they contrast.

The font and colour is also different from the rest of the poster so it stands out.

The red font is rough while the black is just square.
The font take up the whole poster. 

This poster uses yellow bricks to contrast against the green background. Green and yellow are analogous colours. The bricks are just above the center of the poster, so it stands out.

The font is really small and in the corner. There is a lot of empty space.

This poster uses the green car because it contrast with the yellow background. The white text is right under the car, so its probably the next things people will see. The text is white so it makes a green, white pattern with the car. The car is 2/3, vertically, of the poster.

Postcard

I chose the JPG because it good for pictures with many colours and it allows high quality viewing from programs.

The background image is 1440 x 1080

I picked everything so it would contrast against the black background.
The white text on black and the graphic effect around the astronaut.
First I put the background, then I used the wand to paste the astronaut. I then used mask to paste the rover.
I used the stamp tool to make the effect around the astronaut. Finally I typed the words.