You will be coming to my backyard .... I live 10 minutes from the Townsend entrance to GSMNP.
As previously mentioned, it will be hot in July but there are so many shaded areas that you will not find it unbearable.
Let's see, where to start?
Your trip timing should be perfect for the Rhododendron bloom, usually mid July or so, some earlier, some later. These gorgeous white flowers will be everywhere.
In no particular order:
The vistas from
Clingman's Dome (great sunrises)
Newfound Gap Road
The
SinksCades Cove (wildlife, song birds, woodpeckers (5 species) turkey, black bear, coyote, deer) primitive structures (homes, churches, grist mill, etc.) wildflowers
Tremont - Often missed spot (by tourists) Go to the end of the road and park. Grab your camera and hike up the Middle Prong trail (easy hike) You will have the Little River on your left with too many water falls and water features to photograph them all.
Hiking conditions and opportunities are numerous, from easy to strenuous. I would suggest stopping at the Visitor's Center at Sugarlands and asking for current recommendations. While at Sugarlands ask for directions to the Laurel Falls hike.
What to bring (camera gear)
Wide angle lens (for sunrises and vistas, also waterfalls)
70-200 for waterfalls and general use
Macro capable lens for flowers
Polarizer for the water photos ... it will help with all the "green" as well
GND's for sunrises (if you have them)
I use a 500mm for some wildlife, but since you are traveling a long lens may not be practical
Gatlinburg is nice, as mentioned a small tourist area ... Pigeon Forge is a true tourist area (Dollywood, outlet stores, miniature golf, go-carts, etc.)
I suggest "The Peddler" in Gatlinburg for a great meal
Excellent Photographer Reference
The Smoky Mountains Photographer's Guide
Amazon LinkHope this has been some help .... Have a great trip!