Point-and-Shoot 

Point-and-Shoot (P&S) cameras are definitely popular cameras.  Most people utilize there simplicity and compact designs for parties, vacations, and family events.  These cameras are everything the name implies, simply point and shoot.  They are designed so that virtually anyone can use them.  You don't need a bag full of lenses, flashes, and accessories to take great photographs.  Many cameras have built-in flashes, zoom lenses and program settings that allow the photographer to take interesting photographs and still get creative without the need for extra gear.

Point-and-shoot cameras do have limitations.  Unlike Single-Lens Reflex (SLR) or Digital Single-Lens Reflex (DSLR) cameras, the image that the photographer sees in the viewfinder is not the same image that will be recorded onto the film or imaging sensor.  There are two separate lenses.  The primary lens and the viewfinder.  The primary lens records the image, the viewfinder is what the photographer sees.  This can sometimes lead to images that are offset from the original viewfinder if the photographer did not compensate for this.  The ability to add-on or expand the camera system is limited compared to SLRs or other camera formats.  Generally the flash and lens are limited to what was built into the camera.  Some higher-end point-and-shoot cameras have many available accessories.  

Point-and-shoot cameras are great cameras for anyone.  They offer a wide range or options and abilities and can be a great addition to any professional photographers camera bag.  When you don't want to pull out the expensive and heavy camera gear for the family get-together, the point-and-shoot can be a reliable friend.

35mm Single-Lens Reflex 

The single-lens reflex (SLR) camera is gaining popularity.  With the advent of digital single-lens reflex (DSLR) cameras entering most big-box stores, more and more people are understanding the benefits to photographing with a SLR.  The cameras are certainly larger and heavier than their point-and-shoot brethren, but are capable of so much more.  One of the biggest advantages to using a SLR is that what the photographer sees in the viewfinder is exactly what will be recorded onto the film frame or the imaging sensor.  This is obviously very assuring to the professional photographer.  SLRs use a pentaprism to correct the upside-down and backwards image view that is inherent in medium format and large format camera systems.  The pentaprism and mirror translate what the lens is seeing to what the photographer is seeing.  The ability to expand upon the camera system is another major benefit.  Most camera manufacturers have catalogs of lenses and accessories designed specifically for the SLR camera system.  The option to use automatic and full manual settings make them very appealing to professionals and advanced amateurs.  

Medium Format Single-Lens Reflex

Medium format SLRs are nearly Identical to 35mm SLRs.  The exception being the size of the film and the size of the cameras and lenses.  Medium format SLRs use 120 or 220 size film.  This format has been the preferred choice of professional photographers, especially commercial and fashion photographers because of it's large film format, but relatively mobile size.  Larger film sizes have more resolution and finer grain which means that enlargements look better and can reproduce with more detail and accuracy.  Many manufacturers have been producing high-end digital backs for use with some medium format cameras.  For many commercial photographers, this has resurrected their once "withering" medium format bodies and lenses into extremely high resolution digital cameras.

Medium format cameras are also much more expensive than their 35mm counterparts.  The lenses, backs and bodies often fetch a much higher price tag due to the mechanisms, quality and glass that are found in many medium format cameras and lenses.  

Large Format

Generally speaking, large format cameras use film sizes 4x5 inches or larger.  Film sizes range, but common sizes are 4x5, 5x7, 8x10 all the way up to 20x24 inches.  Large format camera bodies are some of the simplest cameras around (aside from pinhole cameras).  The large format camera is generally a monorail or a viewfinder or field camera.  The monorail cameras are best suited for indoor or studio work where the camera will remain on a tripod and will not need to be lugged around by the photographer.  Viewfinder and field cameras are great for location and well, field work because they often fold flat and are lighter than monorail cameras.  The lenses are generally a separate piece that the photographer must purchase.  Unlike 35mm and medium format cameras, large format cameras do not accept roll film (unless fitted with a roll film back).  These cameras use sheet film that is loaded into a sheet film holder in total darkness.   Before the photographer inserts the loaded sheet film holder, he must compose and focus the image on a ground glass that is located on the rear of the camera.  The image in the ground glass is upside-down and backwards.  This can be very disorienting to newcomers entering the view camera realm.  Large format film produces amazing image quality that only gets better as the film size gets larger.  Camera bodies can be relatively in expensive and climb very high.  Older lenses can also be found very inexpensively, but some of the newer multi-coated corrected lenses can be very expensive.  Large format photography forces the image taker to slow down and think about all the steps required to capture a successful image.  Large format photography very fun and quite addictive.

SLR cross section

1.  Lens assembly 

2.  Mirror in down position (image visible in viewfinder)

3.  Focal-plane shutter

4.  Sensor/Film

5.  Focusing screen

6.  Condensing lens

7.  Pentaprism or Pentamirror

8.  Eyepiece  

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Large Format Camera

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