Digital Camera Basics – Exposure Compensation
The built-in light meters in modern cameras are incredibly accurate. The matrix, or evaluative method which measures the whole frame and averages the bright and dark zones to come up with what it thinks is the right exposure. There is also a centre weighted and spot metering modes, which calculate light measurements in similar fashion, but sample smaller portion of the frame. In case of centre weighted, about 20% around the centre of the screen is used to average the light intensity, and in case of spot metering, only about 5% is used.
The camera’s light meter is capable of quite accurate measurements, but there is a problem. Averaging the meter reading works great if the light is evenly distributed in the frame. It doesn’t work as well if you are shooting object positioned against large dark or bright backgrounds.
It’s not hard to understand why a person standing in front of a very bright background, like the midday sky, would be severely underexposed. Engineers who designed those sophisticated camera light meters had to make sure that the camera will produce acceptable images in most light conditions. They were perfectly correct in about 90% of cases, which is quite remarkable. Unfortunately, some of the most beautiful images would be captured when the light conditions fall in those last 10%.
Imagine shooting a winter Olympics skier in a down-hill race. The camera sensor sees a perfectly white image with a tiny patch of colour somewhere in the middle (the skier). Naturally it will decide for us that the image is severely overexposed and will dim it down (reduce shutter speed to average it down). Yes, we will get an image from this shot, but it will not be snow we’ll be seeing, but some grey, ugly mass; and the skier will come out almost completely black.
In those situations it is the photographer’s job to override the camera’s settings to produce correctly exposed picture. How do they do it? Well, I’m assuming they are shooting in AV (aperture priority) mode, which means they set the aperture and the camera light meter decides on the shutter speed. Then, they use exposure compensation.
They must tell the camera that the background IS in fact that white and should be shot as white, and not averaged down to a grey colour. By adjusting the EV compensation plus 1.5-2 stops will produce snow that is white, and will also expose the skier correctly.
Similarly, if you shoot someone standing in front of a very large dark area, like some dark trees or a barn, the camera will measure for the large dark patch and in effect over-expose the person standing in front of it. Read the rest of this entry »
How Smart Is Your Mobile Phone?
Posted by admin in Mobile Phone on April 7, 2013
Today we expect to have a phone that can go anywhere with us, bringing a level of safety and communication along as previous generations never would have believed possible. Our cellular or mobile telephone is like an appendage we can’t seem to live without. From a basic phone that gives users the opportunity to phone home or call emergency numbers to the “smart phones” that provide games, online shopping and surfing, and viewing movies or TV programs there is a phone just right for nearly everyone today. Kids can have their very own phone with their own number if parents OK it.
Cheap mobile phones are basic and disposable
Looking for a basic phone that you can carry along in case of emergencies? Look no farther than the prepaid mobile that costs very little over a year’s time yet provides a means of calling locally or in emergency situations. The users of this little phone generally do not want to “gab” on the phone all day but rather just have a safety harness in case their car breaks down on the highway or they get lost in a strange town. When this phone runs out of minutes it can either be refilled or simply tossed out. The selection among mobile phones is amazing. Choose from a small one to a really small one that is ultra thin. Service providers usually carry a wide variety of name brands as well as some low end models that save you money. The basic mobile phone makes calls as well as receives plus usually can be texted on and will store hundreds of numbers in your own “phone book”. Call forward and call waiting are normal functions you won’t need a “smart” phone to provide, so go for the basic unless you want one to ‘surf the net’ with.
Service plans make the difference in mobile phone priorities
You can get the latest and most expensive smart phone for free on some service plans. You will need to sign up for a one or two year contract and that means you are beholden to them and must remain with that plan for the allotted time but that’s often considered beneficial when it’s with the service provider of your choice. Choose a basic plan or add in family members affordably and share the minutes among your entire family and friends. Long distance need not be expensive any longer either because flat rates have brought the service down to match basic rates worldwide. Read the rest of this entry »
Gadgets – Latest Electronic Gadgets
Posted by admin in Electrical Gadgets on April 6, 2013
The technology has advanced by leaps and bounds. Every year we have certain new inventions, new gadgets developed and introduced in the market. These advancements have taken place because of the development in the computer technology and electronics industries taking place in the recent years. This has made the latest electronic gadgets more popular. The latest electronic gadgets that have been introduced in the recent past are Digital devices, iPods and laptops, mobile phones, LCD televisions and various other technical gadgets. These can also be used for the purpose of gifting on various occasions like birthday, anniversaries, Christmas and many other festivals.
The latest electronic gadgets have been developed keeping in mind the tastes and preferences of consumers, the age group which uses these gadgets. These are too handy so you do not have to take tension as to where you have to keep them. You also do not have to worry about these devices being broken up as these gadgets are made with the latest and the best technology, with the best of raw materials so they provide you utility for a long period of time. Today these handheld gadgets have become a part of our daily lives. Be it the headphones you use for your mobile while taking on the phone, speaker phones for listening to music and also the laptops which can be carried anywhere so you do not have to worry about your work getting pending.
Mobile phones provide you with much functionality apart from you attending the calls. The latest technologies like GPRS and 3D have made these gadgets all the more popular and it has slowly and steadily become a part of our daily lives. Internet is one place where you can find the electrical devices with all the specifications.
Electronic gadgets are not merely for computer fanatics or the youth. Today we may discover a huge range of useful gadgets that is suitable for any age group. For every newer generation, the latest and advanced gadgets are coming up. You can see these devices on various sites that help you know more about the costs of different products and items. You can also order these products on the internet and get them to your place. You need not waste much time in traveling from one place to another when you can easily find these devices on just a click of a button. Internet shopping has become a more convenient way for shopping today. Read the rest of this entry »