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  • Understanding White Balance

    When taking pictures with a digital camera you may notice that sometimes your photos have a colour cast to them. Many people keep their cameras on the auto setting, which attempts to remove the colour cast, but may not always work.

    Digital cameras have the ability to change what is known as the "White Balance&quot (WB). This setting attempts to offset the colour produced by a specific light source to make the colours as true as possible. This post will discuss what white balance is, and how to use it.

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  • How Encryption Works

    Everyday there are possibly millions of transactions made that involve the exchange of personal information. Obviously, those that provide that information would like to know that the information they send is safe and secure. On the Internet making information secure is handled by encrypting the data before it is sent, and decrypting it once it reaches its destination.

    This post will describe the encryption process and how it is used to keep information safe.

    Definition of Encryption

    Encryption is the process of encoding data to ensure that unauthorized parties cannot view it. When data is encrypted, the data is first passed through an algorithm and is converted into cyphertext, which is the encrypted data. To accomplish the encryption, a key or code provided by you is used to encrypt the data, which will make the encryption difficult to crack.

    There are two systems used for encryption: Symmetric-key encryption and Public-key encryption (asymmetric). The next section will discuss the two systems.

    Encryption Systems

    A symmetric-key encryption system uses a secret key or code to encode the data. When the information is passed to another computer, the code is passed along separately. The second computer then uses the secret code to decode the data. A symmetric-key system is fast but is not as secure as the public-key system. If someone were to intercept the data and the code, then they could easily decode the data.

    In a public-key system there are two keys: a public key and a private key. A public key is given out by a secured computer to any computer that wants to establish a secure communication. When the data is to passed from the client’s computer, it is first encoded with the public key and then sent to the secured computer. The secured computer then uses the private key along with the public key to decode the data.

    Number of Public Keys

    So how many keys are possible for encryption? It all depends on the bit strength of the encryption. The bit strength of the encryption can vary such as 40-bit or 128-bit. To get the number of keys, simply raise 2 to the power of the bit strength. For example, for 128-bit encryption the number of possible keys is 2128 or 340,282,366,920,938,000,000,000,000,000,000,000,000 keys.

    Although it may look like determining the correct key is impossible, just remember that computers are getting more powerful, so it is taking less time to determine the key through brute force. This is not to say that your data is not secure, as it still takes a long time to crack 128-bit encryption, at least to the point where it may not be worth while.

  • How Digital Cameras Work

    Over the past few years the digital camera has become very popular with everyone from the amateur photographer to the professional. The digital camera provides the ability to instantly view a photo and either delete or keep it. How is a digital camera able to take and store a photo without the use of film? This post will explain how a digital camera is able to do that.

    The Image Sensor

    Digital cameras include a digital sensor that converts light into electrical charges. There are two types of image sensors found in digital cameras: charged coupled device (CCD) and complementary metal oxide semiconductor (CMOS). Most digital cameras use a CCD image sensor so we’ll focus on that type.

    The CCD has millions of elements that are light-sensitive. Each one of these elements represents a single point in the picture, which is called a pixel in computer terms. For example, a 6 megapixel camera would have approximately 6 million pixels. A megapixel is equivalent to 1 million pixels.

    When light hits one of these elements an electric charge is created with the strength of the charge determining the brightness of the pixel. No charge produces black while a full charge produces white. As you can see, a CCD produces shades of gray and not colour. Colour is produced using a filter within the digital camera.

    Generating Colour

    There are many kinds of filters that can be used within a digital camera to generate colour, but the most common one is the Bayer filter pattern. This type of filter contains a series of rows with one row alternating between red and green, while the next alternates between blue and green. You’ll notice that green is in all rows, why is that?

    The human eye is more sensitive to green colours than to red or blue. To ensure that the images appear as "true colour", there are more green pixels than red or blue. In other words, there is the same amount of green as there are blue and red combined. The image below shows an example of a bayer filter.

    When a picture is taken, the raw output from a bayer filter is a mosaic of red, green and blue pixels. The digital camera then uses a demosaicing algorithm to convert this image into true colours. Each pixel in the filter can be used more than once, and the colour of each pixel is determined by averaging the values from the surrounding pixels.

    Once the image is generated from the CCD and coloured by the filter, the camera than applies any white balancing, sharpening, contrast, and other settings specified by the photographer. This step is skipped if the picture is to be saved in a RAW format.

    Storing the Image

    Early digital cameras stored the images on memory within the camera. As digital cameras evolved, new types of removable memory became available. Digital cameras today can use one or several types of memory including:

    • CompactFlash
    • Secure Digital (SD)
    • Memory Stick
    • SmartMedia
    • CDs or DVDs

    Some cameras can also accept two types of memory, such as CompactFlash and SD, although most only accept one type. No matter what type of memory your camera uses, you will need a lot of room to store the pictures, especially when storing the images in one of the uncompressed formats.

    The most common file format used by digital cameras is JPEG. This is a compressed format commonly used for photographs. JPEG files use a lossy compression, meaning that data in the picture is discarded when the file is compressed. The more a file is compressed, the more data is lost and JPEG artifacts appear. This also means that the file size is smaller. Your digital camera has built-in settings that can be used to control the amount of compression.

    Another common format used by digital cameras is the TIFF format. This is usually an uncompressed format which results in much larger file sizes. Unlike JPEG, however, a picture in TIFF format doesn’t lose any data. You trade memory space for quality.

    Some of the higher-end cameras can also save pictures in a format called RAW. In this format, no processing (white balance, sharpening, and contrast) is done by the camera. This format allows complete control for those that like editing images in photo editing software. These files are larger than JPEG but are much higher quality. One of the biggest differences between RAW and the other formats is that RAW is proprietary. This means that only specific photo editors can be used to modify a RAW file.

    Once a picture has been saved to the memory card, the next step is transferring the pictures to a computer.

    Transferring Pictures

    Digital cameras can store hundreds and possibly thousands of images on a memory card. That’s great, but you would probably also like to delete the old images to make room for the new ones. This is done by transferring the images to a computer.

    Included with your camera is either a USB (Universal Serial Bus) or Firewire cable. These cables are used to transfer data between devices. Your computer will have either a USB or Firewire port, or both. Simply plug in the cable into your computer and then into your digital camera. Turn on you camera and your computer will recognize the camera and allow you to transfer the files.

    I use Windows XP, and when I plug in my camera it instantly becomes a drive letter under Windows Explorer. This allows me to copy the images to my computer just as I would with any file.

    An alternative to using your camera to transfer pictures is to purchase a card reader. Card readers require little power (they get their power from the USB or Firewire port), and they may transfer the files faster than your camera. Without using your camera, you can also save battery power. The one big difference between the card read and the camera is that a card reader may support many different types of memory cards. This allows someone with a CompactFlash card and someone else with a SD card to use the same card reader.

  • How to Buy a New Computer

    Buying a new computer can be very confusing if you don’t know what you are looking for. There are many components that make up a computer, and you may not know exactly what you need to include in your computer. For example, how much memory or hard drive space will you need, or what type of graphics card?

    In this post, I will discuss the various components of a computer and provide a rough guide as to what you will need for each component.

    Motherboard

    If the processor is the brain of your computer, this is the heart. Everything in your computer connects to this single board of chips, which makes it the most important piece in your computer.

    When it comes to a motherboard, I tell people to make sure they get a brand name motherboard, as cheap motherboard could cause problems in the future. Brand names include Asus, Abit, Intel, and Gigabyte. If the motherboard in your computer is from one of these companies, then you are off to a great start.

    Recommendation: If you are not into gaming, photo or video editing, any new motherboard will suit your needs.

    For those that perform the above mentioned tasks, find a motherboard that supports a fast front-side bus (FSB) speed (800Mhz+), and multiple graphics cards.

    Processor (CPU)

    The CPU is the brains of your computer. It is a chip that plugs directly into your motherboard. Unlike a motherboard, you are pretty much guaranteed to buy a brand name processor from either Intel or AMD. Processor speed is measured in Megahertz (Mhz) or Gigahertz (GHz), where 1000Mhz is equal to 1Ghz. The larger the number, the faster the processor.

    Recommendation: For those that do gaming, photo or video editing, but the fastest procesor you can afford, preferably a processor with at least two cores. For everyone else, any of the current processors will be more than fast enough to suit your needs.

    Memory

    When your operating system and applications are loaded from your hard drive, they are stored in the memory of your computer. When looking for computers, the memory is called RAM (Random Access Memory). RAM is extremely fast compared to your hard drive, which is why your applications a run from it. Unfortunately, unlike your hard drive, you don’t have nearly as much RAM.

    Recommendation: Many computers come with at least 1GB (1 billion bytes) of RAM, which is the minimum I would recommend. In this case the more memory you have in your computer the better.

    Graphics Card

    The quality of graphics your can now display on your computer is remarkable. Graphics cards have really advanced significantly in the last 10 years, as well as requiring more power and memory. Some high-end graphics cards can cost more than a new computer, but a blazingly fast. Each graphics card has its own on-board processor and memory to allow your computer’s processor and memory handle the actual application. Most graphics chips are produced by nVidia and ATI.

    Recommendation: For those that play games you will need the most powerful graphics card you can afford. I would recommend that you use two graphics cards in your computer, as long as your budget allows.

    Any graphics card on the market today can handle the day-to-day tasks such as surfing the Web and reading your e-mail.

    Sound Card

    A sound card does exactly what is says: provides the sounds to your speakers or headphones. There are many different sound cards for your computer but if you want a brand you can trust, check out Creative Labs sound cards.

    Recommendation: This part of a computer is not important unless you play many games or do video editing. For most people, even the sound included with your motherboard (if it is included) is all you would need.

    Network Card

    Network cards, whether wired or wireless, allows your computer to connect to other computers. If you have broadband, you will need to ensure that you have a network card. Most computers sold today automatically include a network card, and some have one built-in to the motherboard.

    Recommendation: If you are looking for a laptop, make sure it includes a wireless network card along with a wired one. If you look at desktops, you can go with a wireless card as well, however, if you are connecting to a wire or modem that will be beside the desktop, stick with a wired network card.

    Hard Drive

    Hard drives are the massive storage devices within your computer that contains your operating system, applications and your data. The disk space of each hard drive is measured in Gigabytes (GB), which is equal to 1 billion bytes. For hard drives, I usually stay with brand names because you know your hard drive will perform without issues. Companies such as Western Digital, and Seagate are two that produce quality hard drives.

    Recommendation: Stay with the brand name hard drives, and get the largest hard drive you can afford, especially if you like games, edit photos or videos. You may also want to look into external hard drives for backup purposes.

  • Backing Up Digital Photos

    There is much discussion on the Internet about the best method for backing up digital photos. Some say CD/DVDs are the best media, while others prefer hard drives or tapes. In my opinion there is no right way to back up digital photos as each method has its advantages and disadvantages. I will discuss the various media and their advantages and disavantages in this post, and then discuss the method I use to back up my digital photos.

    Optical Media (CD/DVD)

    CD/DVDs are perhaps the most popular method for backing up digital photos, as most computers now come with a burner and software. Most photo organizing software also include the ability to burn your photos to a CD/DVD.

    Advantages: Very little cost to storing your digital photos, as your computer probably includes a burner. You can buy CD/DVD spindles that include hundreds of blank discs for a few dollars. A single layer, single-sided DVD can hold up to 4.7GB, which means you can store thousands of photos on a single DVD.

    Disadvantages: The biggest and possibly most talked about problem with optical media is that they could develop problems as time passes. This could lead to you digital photos becoming unreadable. To help minimize read problems in the future, only buy name brand CD/DVDs.

    Another disadvantage with CD/DVDs is the fact that they are a progressing technology. This means that in a few years they will be replaced by another form of optical media. For example, the CD is now being replaced buy the DVD, which in turn is slowly being replaced by high-definition DVDs. This means that you will have to eventually move your backups to the next generation of optical media every few years.

    Hard Drives

    Hard drives can store enormous amounts of information, much more than either tapes or CD/DVDs. All computers come with at least one built-in hard drive so you don’t need to buy anything else. An external hard drive, however, is preferred for backing up data.

    Advantages: As mentioned they have massive amount of storage capacity, meaning one hard drive can probably store your entire digital photo collection. You would only have to purchase the drive and no additional media. An external hard drive is very common today, and can connect to your computer through the USB port. This keeps your data safe in case your computer fails and you need to reinstall your operating system. Unlike the other media, hard drives have been around for many years, and although the technology may change, you will still be able to use your current hard drive for many years.

    Disadvantages: The biggest problem that you can run into would be a hard drive failure. Always keep in mind that anything with moving parts can break, and a hard drive is no exception. If you take care of your hard drive, then it should last for many years.

    Magnetic Media (Tape)

    This is not as popular for a home user as it is for a business user. Tapes are popular for a business since they can store much more than a CD or DVD, and they are more reliable.

    Advantages: Tapes, as mentioned, can store a large amount of data, although not as much as a hard drive. Not only can they store a lot of data, but they can also be erased and rewritten many times. If you take care of your tape, then it can last for many years.

    Disadvantages: Out of the media mentioned in this post, tape backup is probably the most expensive. You would need to buy a tape drive, and then the individual tapes, and depending on the type you buy it can be quite expensive. This is one of the reasons tapes or used more in business than at home. Tapes can also degrade if used on a frequent basis, which could cause problems with your data, so just like the other media you will need to take care of your tapes.

    Online

    This type of backup isn’t discussed as frequently because most don’t think about using an online service to store their data. There are many places online that can provide you with enough disk space for your entire digital photo collection, but you will need to research the best Web site that suits your needs.

    Advantages: One of the biggest advantages is that you don’t need to worry about resaving your data as technology progresses. Your chosen online company will do that for you. Another advantage is that the online company probably has a good backup and restore system in place in case of a hardware problem (at least you hope). This will help ensure that you never lose your data.

    Disadvantages: You will probably need to pay a monthly fee to store your data on the servers, and depending on your budget, this may not work for you. You will also need to do much research into the online company first to ensure that your data is safe and secure. The last thing you need is to see your digital photos all over the Internet because someone accessed your backups.

    My Method for Backing Up

    After reading this post, you may be wondering how I choose to back up my digital photos. Here is what I do:

    1. First I copy the digital photos to an external hard drive. I use a Western Digital 250GB hard drive which has more than enough storage space for my needs. This also allows me to pull up the pictures at anytime without having to find a DVD first.
    2. I then backup the same photos to a DVD (usually one for each year). This allows me to keep my digital photos off site in case something happens.
    3. I also maintain my collection of digital photos on an online Web site. This provides extra protection for my photos.

    As you can see I don’t stick with one method of backing up my digital photos. The best thing you can do when backing up your photos is to make multiple copies. This way if one copy doesn’t work, you have another.

    Summary

    I discussed the various media that you can use to back up your digital photos. I have also described the method I use to backup my photos. After reading this post, I hope that you will be able to choose your preferred method to keep your photos safe for many years. Remember: always make multiple copies of your data.

  • Converting Digital Photos for E-mail or the Web

    There have been many times in the past when someone has sent me an e-mail with picture attachments. I don’t mind picture attachments, if they are resized. Many times the pictures have not been resized and I end up downloading 5 files that are a combined 10MB. Even on broadband this can take some time.

    In this post I will outline the steps I use to resize my digital photos so they can be easily sent by e-mail or posted to a Web site. The steps outlined are general enough where they can be used by most photo editors as they all have the needed features.

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  • How to Make Money Online

    There has been much talk on how to make money on the Internet. There are many ways to make money, and I will discuss some of the ways in this post.

    Advertising on a Web Site

    If you have an existing Web site this is perhaps the easiest method to implement. There are many advertisers on the Internet that you can sign up with, and they will in turn provide you with code to add to any Web page. Once you add the code, advertisement will then start appearing on the page, usually specific to the topic discussed on the Web page. Many people choose Google’s AdSense for the advertisements, although there are many other companies that can also provide advertisments. After doing a search on the Internet you will find many people who have had great financial success with advertising on their Web site.

    See also

    Auction Selling

    I decided to name this point as “Auction Selling” and not “eBay Selling.” I did this because there are many other auction sites online that many people have chosen over eBay, most notably because the fees are lower. Regardless of the fees; however, online auction selling can be very profitable, any many people successfully run a home-based business just by selling on one of these sites.

    See also eBay.

    Online Store

    This is probably the most involved method of making money online, as it requires you to manage your inventory, setup merchant accounts, handle shipping, create a Web site storefront, and many other things that go along with a business. If you prefer to just create the Web site to sell the products, and have someone else do the inventory management and shipping you may want to look into dropshipping.

    See also Shopster.com.

    Summary

    As with any business venture, those listed in this post require hardwork and time. Making money online is not a “get rich quick” scheme, and you may find that you will be working as many hours as a regular 9 to 5 job.

  • How To Generate Web Site Traffic

    There is much discussion on how to generate traffic to your Web site, but I decided to list a few points on the methods I like to use.

    1. It’s All About Content

      You may have heard that "content is king." What does this mean? Visitors to your site like to read updated and unique content. This means you must update your Web site on a regulary basis to keep your visitors coming back for more. Search engines also love unique content. The more content you have the more you will get listed in search engines. When you first start a site search engines may be your main traffic generator so it’s best to get listed in them. Also remember to check your spelling and grammar.

    2. Write Content For Your Visitors

      When writing your content, write it for your visitors and not search engines. This means don’t load up the content with keywords that is hard to read and understand. You need your visitors to keep coming back and not the search engines. If you write unique content the search engines will list you…don’t worry.

    3. Linking to Your Web Site

      This is a big part of getting listed in search engines, and thus getting more traffic. The more quality Web sites that link to yours, the better search engine rank you will receive. You should have sites that share the same niche as your site link back to you. When a search engine indexes the other site, it will find the link to yours and then index your site.

    4. Get Listed in Directories

      Besides search engines, there is another type of site you should get listed in: a directory. A directory is a list of Web sites that are organized into various categories. Many of these Web sites are very popular so getting listed in one of them can help you generate traffic. A bonus to getting listed in a directory is that they usually have a high page rank, which will help increase yours. Do a search for directories that contain your Web site niche and get added.

      5. See also Open Directory Project.

    5. Forums and Blogs

      I put these two into the same point because they essentially do the same thing: you leave comments and a link to your Web site. Let me explain. Do a search for a forum that is related to your niche, and sign up. Add your Web site name and URL in your signature to your profile. Now leave comments to some of the posts in the forum. Search engines will index forums, and at the same time will find the link in your signature which will once again act as a link back to your site. Leaving comments in blogs acts the same way as comments in forums.

      See also Website Babble.

    6. Write Ezine Articles

      Ezine articles are similar to magazine articles except they appear online. There are several free Web sites that allow you to write your own article. These are great as you can become a well-known leader in your niche. You should then put a link at the end of your article to your Web site, so anyone reading it can click the link and go to your site. Search engines will also index any article you have written. Other sites that also enjoy your article may print your article with the link to your Web site included. You can’t get any better than that for something that cost you nothing but time.

      See also Ezine Articles.

    7. Good Site layout

      This one is important to get your visitors to return. Make sure your site is easy to read and navigate. Having light grey text on a white background may be hard for some to easily read, so use black instead. A visitor to your site should be able to understand how to navigate within the first few seconds of loading the page. Keep the navigation simple, such as a menu on one side of the page or across the top.

    8. Submit Your Feed

      If you have a blog make sure you submit your feed to various Web sites. A feed is the content that you have created in a specific format. You can also create feeds for a regular Web site as well.

      See also Feedburner or Ping-o-matic.

    9. Advertising

      This point is not one to generate traffic as much as revenue, but I felt it important to list, as it can reduce your traffic. Placing advertising on your site is a debatable issue. The issue that is up for debate is when should you place advertisment: when you first start your Web site, or when you get a large number of visitors? My take on the issue is that it is your choice, just don’t load your site with advertisment. I hate sites that display advertisement at almost all possible locations on a Web page: top, bottom, left and right. I prefer that the advertisement be in one location and blend into the site and not stand out.