Putting type in a poster photo can be problematic, since the photo can vary from light to dark. Dark type can’t be seen in dark areas, and vice-versa. Often you’ll want to put type in a photo to label or explain things. Here’s my trick for doing it successfully.
First of all, set your type as yellow. Sometimes that’s all you need to do unless there are stretches of yellow in the photo. If not, get the yellow type the right size and position. Then, duplicate the text box, change the type to black, and send it backward behind the yellow type. Nudge it with the arrow keys to be a little lower and to the right to the yellow type. This gives you a drop shadow that lets the yellow type be read when it crosses a light spot in the photo.
Voila! Type that can be read no matter what the photo behind it is.