What is themes in photography...??

Focus
The adjustment to place the sharpest focus where it is desired on the subject.

Aperture
Adjustment of the lens opening, measured as f-number, which controls the amount of light passing through the lens. Aperture also has an effect on depth of field and diffraction – the higher the f-number, the smaller the opening, the less light, the greater the depth of field, and the more the diffraction blur. The focal length divided by the f-number gives the effective aperture diameter.

Shutter speed
Adjustment of the speed (often expressed either as fractions of seconds or as an angle, with mechanical shutters) of the shutter to control the amount of time during which the imaging medium is exposed to light for each exposure. Shutter speed may be used to control the amount of light striking the image plane; 'faster' shutter speeds (that is, those of shorter duration) decrease both the amount of light and the amount of image blurring from motion of the subject and/or camera.

White balance
On digital cameras, electronic compensation for the color temperature associated with a given set of lighting conditions, ensuring that white light is registered as such on the imaging chip and therefore that the colors in the frame will appear natural. On mechanical, film-based cameras, this function is served by the operator's choice of film stock or with color correction filters. In addition to using white balance to register natural coloration of the image, photographers may employ white balance to aesthetic end, for example white balancing to a blue object in order to obtain a warm color temperature.

Metering
Measurement of exposure so that highlights and shadows are exposed according to the photographer's wishes. Many modern cameras meter and set exposure automatically. Before automatic exposure, correct exposure was accomplished with the use of a separate light metering device or by the photographer's knowledge and experience of gauging correct settings. To translate the amount of light into a usable aperture and shutter speed, the meter needs to adjust for the sensitivity of the film or sensor to light. This is done by setting the "film speed" or ISO sensitivity into the meter.

ISO speed
Traditionally used to "tell the camera" the film speed of the selected film on film cameras, ISO speeds are employed on modern digital cameras as an indication of the system's gain from light to numerical output and to control the automatic exposure system. The higher the ISO number the greater the film sensitivity to light, whereas with a lower ISO number, the film is less sensitive to light. A correct combination of ISO speed, aperture, and shutter speed leads to an image that is neither too dark nor too light, hence it is 'correctly exposed,' indicated by a centered meter.

Autofocus point
On some cameras, the selection of a point in the imaging frame upon which the auto-focus system will attempt to focus. Many Single-lens reflex cameras (SLR) feature multiple auto-focus points in the viewfinder.

What is new in digital photography?

         The market of digital cameras has encountered an incredible increase of market share over the past few years. Photography can be viewed as an art form. This is a great way for the photographer to express what he sees and share his work and creativity to the public. The digital camera, like any electronic device, continues to come up with new and better ways to take pictures. Some digital cameras are made to allow users to take incredibly beautiful photographs with a very high resolution with a touch of a button. More and more photographers prefer to use a digital camera over a film camera. Many companies are responding to consumers who want a camera that's easy and fun to use and that allows them to preserve their family memories. Also, they offer a better choice of what they can do with their pictures by improving the quality of the images with high resolution. The digital camera offers different people of different levels to achieve what they need and want.

                The newer digital cameras allow the consumer to send reduced size email pictures with lots more clarity and visibility. They also offer menu options where you can edit your picture from the camera without the need of a computer. It can adjust the brightness of your dark pictures, detect and correct red-eye images from your camera. Other fun features give vibrant and sharp images and also allow you to take pictures either in landscape form or portrait. Camera sizes have decreased dramatically as well.

              Until recently, professional and serious photographers have used film photography as their main choice because of its high resolution, telephoto zoom lenses, fast shutter speeds, and the ability to take many pictures rapidly. But lately, digital photography has advanced to the point where photographers in many professions, including studio photography, have included digital cameras in their arsenal, or use them exclusively. Good quality, affordable consumer grade cameras are now available for around $500 which rival film camera resolution. For action photographers, one of the complaints about digital cameras has been the time it takes between snapshots. This is one of the things that has improved dramatically in digital cameras. In fact, many models of digital cameras, including cell phones, can also double as digital video recorders. In this way, an action photographer can advance the video frame by frame and choose the best frame as a photograph. The ability to adjust the aperture shutter speed, and to manually focus the camera have long been abilities of good film cameras, and digital camera manufacturers have known that in order to win over the serious action photographer, they have had to solve these problems as well.

             One of the advantages of the digital camera lately for the professional photographer is the decrease in price of flash memory chips and portable storage devices. This inexpensive storage makes taking thousands of pictures much easier than trying to keep track of many rolls of film. All of the image files are date stamped, searchable, and the results of the photo are instantly viewable on the camera's display. A newspaper photographer, for example, would be able to quickly choose the best pictures, without developing them, and upload them into the newspaper's network quickly and efficiently. For the photographer who would like to print the picture quickly without using a computer, there are many picture grade pictures on the market where you can hook or dock your camera directly to the printer. The real news is in how inexpensive these devices are. The real cost is in the paper products and ink.

What is Food photography and food stylist ???

            Food photography is a specialization of commercial photography, aimed at producing of food for use in advertisements, packaging, menus or cookbooks. Professional food photography is a collaborative effort, usually involving an art director, a photographer, a food stylist, a prop stylist and their assistants that tended to be shot and composed the way people were used to encountering their food, laid out on a table setting and shot from an overhead perspective from the point of view of the eater. The Stylists accordingly arranged the food to appear good from above, with the items arranged flat on the plate and clearly separated from each other. Later, romantic lighting, shallower angles and more props “en vogue” came. Most recently, the prevailing trend in Western commercial food photography is to present the food as simple, clean and naturally as possible and with little props, often using effects such as selective focus, tilted plates, and extreme close-ups. This complements trends in professional cooking to make the food more visually interesting. For instance, the height of dishes tends to increase and their elements are often layered, which lends itself well to narrow-angled shots.

              The role of the food stylist is to make the food look attractive in the finished photograph. The main difference between how a home cook or chef may present food and what a stylist does is the time and effort a stylist takes to carefully and artfully arrange the food. Also required is the visual know how, and ability to translate the perception of taste, aroma and appeal that one gets from an actual dish, to a two-dimensional photograph. Food stylists have culinary training; some are professional chefs or have a background in home economics. In addition to knowledge of nutrition and cooking techniques, food stylists must also be resourceful shoppers. As creative professionals, they envision the finished photograph and style the food accordingly.

The process of food photography begins with the purchase of the food and ingredients. Because only the most visually perfect foodstuffs are acceptable and multiple backup or test items are usually needed, this is a very time-consuming process. The best-looking of the purchased items is selected and marked as the "hero", example: the item that will be featured in the photograph. During the setup and for test shoots, it is represented by a cardboard stand-in.

The actual photography takes place in a studio under controlled lighting conditions. The light, background and setting are carefully prepared so as to present the food in an as attractive way as possible without distracting from it. The color and texture of the background is selected so as to effectively complement that of the food and to assist with its lighting.

Styled food is usually marked as inedible and discarded after the shoot, because it may have been handled or treated in ways that make it unsafe for consumption