Colours

The colours that I see in the photographs are : green, white and pink.

Two corrections:

1) The first-person personal pronoun " I " is always capitalized in English. 

2)  The sentence is complete only with a period ( . ) or an exclamation mark ( ! ) (A question mark ( ? ) can also end a sentence, but here it does not make sense.

And one suggestion to improve the style.

The sentence flows more smoothly if we leave out the colon ( : ) and say simply, ".....in the photograph are green, white and pink.