Large format seems like an extinct branch of photography to the uninitiated, but the format never went away. Actually, it is finding a new wave of appreciation among film photographers. There are a few reasons for the resurgence - there is no digital equivalent sensor size, nor is there a digital camera body capable of tilts, shifts, swings, rises and falls (with the exception of some specialty lenses). Used equipment is found online in abundance, and some entrepreneurs are even making new cameras such as the Intrepid Camera Company, Stenopeika and others.
The jump to large format
As for major changes in your photography workflow, the jump from digital to film is the biggest. You need to find a lab or learn to develop film yourself and then either scan the negative or darkroom print your images. Most people will start with either 35mm cameras (because they are the most similar to consumer digital cameras) or medium format systems such as the Hasselblad 500 (because the cameras work in the same way as 35mm ones).
The jump from small to large format film is a little easier. With large format, a few things change. Firstly you no longer need to get emotionally attached to a single manufacturer. You can pair anyone's lenses with anyone's bodies and choose any film holders for the negative size you have chosen. For bodies, you can choose between studio monorail systems which are the cheapest way to get going down the rabbit hole, or fold-able field cameras that have more restricted movements, but can fit in a backpack.
There are also a few extra pieces of kit your smaller camera systems may not have needed - lens boards, sheet film holders, a focus loupe and a dark cloth. Tripods and cable releases are no longer optional - you are going to need them to get even basic shots.
What is it good for?
Taking one photograph really well. This process is the antithesis of 'spray and pray'. A lot of time is spent picking and tinkering with the composition. It takes so long to set the camera up that you don't want to waste that time on a mediocre image.
Tilts and shifts by design. And rises and falls, too. The cameras are made to move the lens around for perspective control and plane of focus manipulation.
MASSIVE negatives. They dwarf the grain even in 400 speed film.
What's the compromise?
Large format is not small. No way are these cameras going to fit in your pocket. Or small bag. Not even a medium bag. With a monorail camera, even a large bag is often insufficient. The compact Intrepid camera, on the other hand, easily fits in a backpack with a couple of lenses.
Forget about a quick snapshot. By the time the camera is set up, focused, shutter cocked and film holder inserted, a good deal of time will have passed. If you have a human subject, you have to keep their attention during setup and focusing or else there will be some long silences.
Lots of lens research required. You need to figure out which lenses cover your negative, and if you want extra coverage to accommodate small or large movements on the camera. Fast lenses allow for easier focusing via a bright image, but slower lenses are siginificantly smaller and lighter. You also need to make sure your body can cope with ultra-wide angles (75mm or less) or very long lenses (300mm or more) or if it needs special bellows or lens boards to cope with them. A great list of lens stats to get you going can be found at www.largeformatphotography.info.
What's in my camera bag?
Cameras: Intrepid 4x5 folding field camera
Lenses: Schnider 65mm f5.6, Schnider 90mm f5.6, Calumet 150mm f5.6, Rodenstock 210mm f5.6, Rodenstock 300mm f9
Accessories: Lens board for each lens, film holders (9), focusing cloth, cable release