No Photos
No Photos Allowed
expression
撮影 is photography. 禁止 is prohibition. So if photography is prohibited, then we can assume there's a no photos or no photos allowed rule in place.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own. Will help to know the words 撮影 and 禁止.
この幼稚園では、子どもたちの発表会は撮影禁止です。
At this kindergarten, photography and filming are prohibited during the student recital.