Q: Does backup save photos

It does, assuming that the photos aren't already on iCloud (from Photo Stream or iCloud Photo Library). See About backups in iCloud and iTunes - Apple Support

However, it is not a great idea to rely on it solely. Note that a backup can only be used to do a complete restore to your existing device or to a new device of the same type. I strongly prefer also having a copy of the photos on other device (e.g. a computer) where I can visually verify that they are in fact there and have them included in the backup of that device.