Contrast

This is my original image. It was very under-exposed.

I used curves in order to modify the image.

This picture was also under-exposed.

Once again I used curves to modify the contrast of the image.

This is also under-exposed.

I used curves to modify the image.

This was an under-exposed picture of Christmas lights.

I used levels adjustment to modify this image.

This is an under-exposed picture of a house lit up for Christmas.

I used levels adjustment to modify this image as well.

This was a slightly under-exposed picture of a flower.

I used levels adjustment to modify this picture as well.