Archive for the ‘Learning tech’ Category

Digital Photography Techniques – How Digital Cameras Capture Photos

Tuesday, January 17th, 2012

I wanted to talk to you about the concept of digital cameras: How they actually function and take photos. I’ll skip the technical explanation as much as possible but I want you to understand the concept so that you can actually take better photos in the future.

Let’s begin with the camera’s metering. The camera works by analyzing the brightness of the light from the subject and adjust the camera settings accordingly (If you are using automatic or semi-automatic modes). There are normally three metering mode in most digital cameras: ‘Multi-segment’, ‘Center-weighted’ and ‘Spot’.

‘Multi-segment’ metering enables the camera to meter the light falls on all parts of the sensor. This mode is suitable for wide-angled photography like landscapes.

‘Centre-weighted’ metering allows the camera to meter the light falls on the center bracket of the sensor. This mode is suitable for more focused photography like sports and portraits

‘Spot’ metering allows the camera to read the light falls on the absolute center point of the sensor. This mode is appropriate for discreet and isolated subjects like macro photography

Take advantage of these modes and read the desired light. Once done, lock the exposure compensation (this setting is available mostly in DSLRs), and recompose before capturing the photo.

Now that you know how metering works, let’s talk about the subject brightness range. Unlike our eyes, your camera sensor does not have a large brightness range over a subject. The maximum possible range is 9 stops. The sensor takes black as darkest and white as brightest. Therefore the neutral compensation of a sensor is called neutral gray. (On another related matter, this explains why sometimes it is advised to use neutral gray color as a reference for white-balance settings).

There’s a simple way to know whether the composure you make is out of the brightness range of the sensor. Switch your camera to aperture priority and use ‘Spot’ metering mode. Using a constant aperture, point your camera to the brightest region of the view and then to the darkest region. If the shutter-speed adjusts more than 9 stops, then the composure is out of range and the image will either be overexposed or underexposed.

This is when a photography technique called HDR kicks in. HDR stands for High-Dynamic-Range, and it is a photography method that allows the photo to extend to a larger brightness range. The procedure for this technique is simple. Take three photographs: one underexposed, one well-exposed, and one over-exposed. Then use software such as Photomatix Pro to merge the three photos together and generate the HDR image.

Basic Photography Technique – How Does A Camera Work?

Tuesday, January 17th, 2012

Don’t go crazy buying an expensive camera, but you’d better take a little time to find out what camera you’d like. Here are some basic photography technique of a camera.

Basically, all cameras are the same and, given identical film and settings, a cheap camera will take the same photograph as an expensive camera. More money doesn’t directly buy your more quality but more control over the image.

A camera is a box with a hole in it. You can make one out of a shoe box with a window of transparent paper on one side and a small hole in the opposite side. Physics teachers call this a ‘pinhole camera.’ Adding more controls, mainly to do with the lens, produces different types of cameras.

1. Disposable Camera.

These one-time use cameras are easy to carry and take surprisingly good shots. They are great for people shots at parties.

2. Compact Camera.

Perfect for snapshots. I like a small, pocket-sized camera with a flash (for people’s faces), a self-timer, a wide-angle lens (28mm for impact), and a panoramic mode (looks cool!). The downside to not having a zoom is that you’re limited to the lens provided.

3. SLR.

The choice of amateur and professional travel photographers. The Single Lens Reflex feature which allows the viewfinder to look through the main lens instead of its own fixed lens allows you to remove and replace the lens. Interchangeable lenses give you more creative control of your shot. You can make a super-wide shot with a ‘short’ lens, or enlarge a very distant object with a ‘long’ lens. You can also control the aperture (the size of the hole) which allows you to decide what is, and what is not, in focus. The downside to the SLR is that you now have more equipment to buy and carry.

4. Medium- and Large-Format.

These are bigger versions of the SLR camera which allow you to use larger (and thus higher resolution) film. Mainly used by stock photographers, the equipment is large and heavy and, therefore, inconvenient for basic travel purposes.

5. APS.

The Advanced Photo System (called Advantix by Kodak) uses a smaller film – 24mm instead of 36mm – which means the cameras are smaller and lighter. This is good for travelers. However, because the APS is new, there is currently a smaller range of equipment suppliers and film developers available.