Sorry, can't help you with a travel loop itinerary but looking at my (amateur) photos, these are some locations I like:

from observation level of Columbia Center on a clear day

Bainbridge ferry looking back at/towards Seattle

Pike Place (of course)

Space Needle (of course)

Smith Tower

Seattle Japanese Garden

there are a couple of interesting flatiron bldgs. ("Seattle Times Bldg" and Triangle Hotel & Bar)

Snoqualmie Falls

Whidbey Island

Poulsbo

Bloedel Reserve

Port Townsend

Hurricane Ridge

Dungeness sand spit

Crescent Lake

Here are other Washington State photo location suggestions submitted by photographers:
http://www.photolocationsguide.com/states/washington/washington.htm

Basically Olympic NP has a wilderness core with roads running around the periphery, with a couple that actually penetrate a little distance into the park proper.

The relatively accessible bits are on the northern edge (Hurricane Ridge, Lake Crescent) - easily accessed from Port Angeles, and on the western edge, including the two famous rain forest valleys, Hoh and Quinault, and the portion of the national park that forms the "coastal strip." To get a feel for the park you really need to see both areas, and they're not especially close to one another. Lodging in the western/coastal part of the park is not very plentiful, with only one or two places in the park along the coast, and a handful in the towns of Forks and one or two other locations. It's possible to visit the northern coastal areas in day outings from Port Townsend, but it involves a lot of driving. Most people choose to base their visit of that area in some place like Kalaloch (actually in the National Park) or Lake Quinault at the southwestern edge of things.

In allocating your time, I'd probably say you'd need at least one day/night in Port Angeles and two on the coast, since the Hoh Valley is worthy of much of a day, as are the beaches. Some of the beaches are fairly accessible, others require a bit of a hike. As a photographer you'd probably want to spend at least one sunset at one of the beaches; they can be spectacular.

So the ONP part of your trip should probably include a day to get to PA, one to visit Hurricane Ridge etc., then on to the coast for at least two more nights, so call it 4 nights on the Olympic Peninsula altogether.

I'd probably do a counter-clockwise loop around the peninsula, then exit by heading east (use US 12) straight to the Mount Rainier area. I'd actually spend the night at the Crystal Mountain ski resort - http://www.crystalmountainresort.com/ - where you could ride their gondola to a (pretty decent) restaurant with a drop-dead stunning view of Mount Rainier. The view from the Summit House restaurant at sunset is to die for.

The next day head into the park proper to Paradise Inn for more photo ops, then I'd recommend you continue right over the Cascades into the Yakima Valley, where you'd see the remarkable transformation of the landscape from the "wet" west side of the state to the high-desert scenery around Yakima. Spend that night in the Yakima area, maybe at one of the many wineries in the Yakima Valley.

The next day continue north on US 97 through ranching country and over Blewett Pass. Detour a couple of miles for lunch at Leavenworth, a faux Bavarian village along US 2 a little west of US 97. Then continue north on US 97, then west on WA 20, with your stopping point at Winthrop, in the beautiful Methow Valley. Great "old west" scenery around here, even if some of the buildings in Winthrop have taken that theme a little far.

The next day, travel west on WA 20 through spectacular mountain scenery (North Cascades National Park) then continue on WA 20 onto Fidalgo Island, then across the (fabulous) Deception Pass onto Whidbey Island. Stop at Deception Pass State Park for some great views of the churning water below the high bridge. Spend that night in either Coupeville or Langley on Whidbey Island, both very cute waterfront villages full of galleries, cafes, etc. Again, more great photo opportunities on Whidbey.

Finally, return to Seattle via the ferry from the south end of Whidbey into Mukilteo (very cute lighthouse) and via WA 526, the "Boeing Freeway" that passes the Boeing widebody plant, biggest building in the world. If time allows, stop and take the Boeing factory tour - larger than life stuff. http://futureofflight.org

To recap, here's the itinerary. It's pretty packed and covers a lot of ground, but there aren't any drives that are longer than 4 or 5 hours, and most are under that.

Day 1 Seattle - PA via Bainbridge Island ferry
Day 2 North Olympic NP
Day 3 West Olympic NP
Day 4 W. Olympic NP, then to Crystal Mt.
Day 5 Mt. Rainier to Yakima
Day 6 Yakima to Winthrop
Day 7 Winthrop to Whidbey
Day 8 Whidbey to Seattle
Day 9 Seattle - home

http://goo.gl/maps/xdYMd

Typo - Port Townsend. Port Angeles.

I think the most spectacular scenery is driving east from Seattle out over the North Cascades Highway. Winthrop, Mazama, Methow river valley area. Absolutely stunning.

I like Gardyloo's itinerary. If you want to go south to see Mt. St Helens, Turn right on US 12 when leaving Mt. Rainier.
Go west through Packwood to Randle and turn south on FS 25 which is paved all the way east of Mt. St. Helens to Carson on the Columbia Gorge (WA rt. 14).
I'm not that thrilled with Yakima.

We've done most of what Gardyloo recommended above though in separate trips. In ONP, we stayed at Lake Quinault Lodge for 4 days and visited Kalaloch, Third Beach and Ruby Beach (lunched at Kalaloch). Took a really amazing tour from the lodge into the rainforest and surrounding area - really well done, lots of photo opportunities. Swimming in lake and casual days at the Lodge. Quick stop in Port Angeles (great ice-cream!). Did not do Hurricane ridge etc. as we were heading to Hood Canal for a few days with family to round out the trip.

On another trip over 2 weeks we did Leavenworth, Lake Chelan (boat to Stehekin, wine tasting, playing in the lake, blueberry picking), Winthrop (stayed at Freestone Inn), and Whidbey Island. We had a family timeshare in Lake Chelan and a rental house on Whidbey so can't really recommend lodging but we really like Langley. Stop at Greenbank farm for pie. Really great trip.

Mt. Rainier is awesome, lots of photo opportunities especially if it is a clear day.

A couple of additional notes on North Cascades Scenic Highway:
Washington Pass Overlook, 20 miles outside Winthrop, awesome vistas;
Rainy Pass 1 mile paved hike to Rainy Lake, picnic (wildflower meadows, a waterfall and glacier viewing platform), off Highway 20, 38 miles east of Newhalen;
Happy Creek Forest Walk – old growth boardwalk loop. Milepost 135 off Highway 20.
And, stop at Cascadian Farm. Pretty interesting lunch stop.

I'm very familiar with the areas Gardyloo mentions, and I'm thinking this is one of the best itineraries I've seen on this website. Specific to the question asked, and filled with lots of great info. If you choose to follow it you will be richly rewarded. You might want to do a little research on the great Montana Ice Dam Floods prior to traveling north from the Yakima area. You'll appreciate the dramatic scenery in Eastern Washington a lot more knowing how it got that way. http://hugefloods.com/Ice-Age-Floods-2.html

Thank you! Thank you! THANK YOU!
I have to say that I <ul>finally</ul> have some clarity on the itinerary thanks to Gardyloo and the additional suggestions are appreciated as well.

?? Any ideas on where we should spend our first night??
We are landing at 10PM at night in Seattle.
We would probably leave the airport after 11 once the luggage and rental car are collected.

Stay close to the airport. You might even think about collecting the car in the morning - it might save a few bucks on rental charges. (Use the hotel vans the previous night.) All the rental cars have been moved from the central garage at the airport to a purpose-built rental car center that requires a shuttle bus; with bags etc. it can be a nuisance. Stay at an airport hotel without a car, dispatch your husband back to the airport in the morning on the shuttle, he picks up the car and comes to fetch you and luggage at the hotel. Easy peasy, and quicker/faster in the evening.

There are several okay hotels near the airport; you might even want to try out Priceline (3-star or higher) to save a few more bucks. They all have free shuttles.

Definitely stay at or near the airport (not usually recommended but makes the most sense for your trip).

Loop around the Olympic peninsula and on the way back to Seattle (or the airport) you can visit Mt. Rainier and/or Mt. St. Helens, depending on how much time you have left.

http://www.flickr.com/photos/mksfca/sets/72157622991196341/

@Michael - nice photos esp of Mt St Helens - gotta try to get there too....