Traveling
The weather on Iceland is changing pretty fast and you should be prepared for showers of rain with rain capes and sturdy shoes. If you are only on Iceland just for photography you should think about renting a camper because this will allow you to stop and rest wherever you want and be on location as the sun rises or when the light is best for you.
If you like adventures and places that are not that touristic you should rent a 4x4, because that's what you need to get towards the center of the country through rough gravel roads and rivers that have to be passed to continue the journey. Anything else near the 1 around the island is pretty easy to reach with any car during the summer time.