Depending on how much time you have, and if it is your first time, some recommondations (I have been there six times bow, spring, summer, winter):
- auroras are nice, if you see them, I never did
- the landscape is special, anywhere you go
- if it is your first time, well, you have to go to the typical places (Golden Circle, ice lagoon), don't concentrate on those so, they are photographed to death, everything else is equally beautiful and nothing people saw millions of times already
- the Bloon Lagoon is a tourist trap, pick another spa to visit, there are plenty
- go self-driving, is is easy and simple, and as a photographers couple you will enjoy the added freedom immensly
- if you have enough time, take the ring roud for a round trip around Iceland, the newly christened Diamond Circle in the north is as beautiful as the golden one and much less crowded, go whale watching in Husavik if possible, Myvatn is quite the place as well, such a round trip can be done in around a week to ten days
- if you have even more time, add Sneafellsness (one day) and the West Fjords (easily another 3-7 days, depending on itinery), the latter is closer to the original Iceland before it became an Instagram-able destination
- if you have even more time, and are comfortable driving "off-road" (off-road driving is illegal im Iceland, so don't, but the highland roads have their share of river fordings and the roads are more like pists in Africa) consider renting a 4x4 (a Dacia Duster is a great alternative and can be rented with a roof top tent) and cut through the highlands from the south to the north; this will add 2-3 days to a stabdard ring road trip but is well worth it
- focus on landscapes, wildlife is limited and Puffins are out at sea already since July/August
- organize your accomondation yourself, e.g. through booking.com, a lot of farmers built snall chalets all over the island, beats hotels for price and comfort as well as availability and keeps money with the locals
- besides some glacier hiking (recommended, as long as there are still glaciers left, I'd pick Skaftafell over those at the ice lagoon) and whale watching there is no real need for organized tours
- a bit west of the ice lagoon is a smaller one, a bit up the hill, less well known, less crowded equally icebergy
- if time allows, consider taking the ferry to the Westmaner islands (adds another day to the ring road trip)
- respect the nature, don't go off marked paths, be aware everything that grows there tales years so don't damage the flora
- respect nature, some spots near the sea can be dangerous if you do stupid things (getting to close to waves, ignoring the tides), as can be glaciers if you don't know them
- enjoy your trip, Iceland is a stunning place regardless of time period, with beautifull spots after every corner
- bring good (!) outdoor clothing: gore-tex or similar hardshell, multiple under layers, hiking trousers that dry quick and easily, solid hiking boots, gloves and stuff in case it gets cold and / or windy
- be ready to test the weather sealong on your gear, that's how I learned to trust it blindly, you and your gear will get wet unless you are extremely lucky with the weather
If you want a more detailed list of places, some of the beaten path, to visit and a realistic route that allows for a decent amlinz of photo stops, let me know. One final thing so, if you don't have limitless time, try not to shoot each and every landscape with a tripod. There are so many beaitiful spots, you don't have time for that. Be ready to shoot hand held after short hikes or litterally from the side of the road. And believe be, that is more than enough. Keep the tripod stuff for those special places like waterfalls or night shots, almost everything else can be done handheld.
Once I have access to my images, I'll share some from the last trips.
