Photography as always been about choice. If you two photographers the same subject at the same time, you would end up with two very different collections of photographs. every thing effects what the final picture will be. The lens, the size of film, Digital, Color or black and white. this are all the things that a photographer has to think about when going out to a shoot.
The advantages of 35mm is that it is common. you can still go online to day and get a bundle of 35mm film. the other advantage is that you get 24-36 exposures per role. so its more economical than medium format where you only get 12 exposures. 35mm has a distinct look. with it you can get a shallow depth of field even with a wide angle lens.
Bigger is better. Because the film size is over double that of 35mm you get a higher quality image. this means that you can create prints that are larger then that of 35mm. there is also a wide range Color that medium format has. this allows capturing the brightest and the darkest subjects with out being under or over exposed
This is a 35mm Digital camera that take 35mm lens, but the digital sensor is not 35mm its about 1.7x smaller then 35mm. this means that all the lenses are cropped by a factor of 1.7. so 50mm lens on a 35mm camera will look like 85mm lens. this makes it very difficult to get a wide 35mm lens for APS-C Sensors cameras. the advantage is the price. an APS-C Digital camera will cost more then half that of a 35mm digital camera. there is not much of a quality loss, but if you like wide angle lens and don’t use a lot of telephoto lens then 35mm is a better choice.
digital cameras are getting smaller and smaller and they stiill deliver quality images. The Gopro hero 3 is an example of that kind of camera. you can take them underwater. stick them on top of a car, or even glue them to an R/C Airplane. the sky is the limit. the only disadvantage is you have one choice of lens. Fish eye wide angle.
3D cameras have come and gone through out the ages. some of the first cameras invented were 3D cameras. 3D has continually come into and out of photography fashion. But will it ever stay. Some people it makes sick. a small group of people like it, while others don’t get it. 3D cameras take two photos at the exact same time. one from the left and one an inch to the right. they have to be synced up exactly. same focus, same lens, same shutter speed and at the same time. when we look at a 3d photo with anaglyph glasses the red side only allows the left eye to see thought the left camera lens photo. The blue side Allows the Right eye to see the right lens photos. and the differences in the left photo and right photo is what makes the images have depth.