photo techniques and technology


The basics of Photography

I think there’s something to be said for just grabbing a camera, trusting the meters, and pointing and taking what you see. However this can only take you so far. An even basic understanding of how a camera works and the terminology surrounding them and photography in general can vastly improve someone’s ability to take pictures. So for today I’m going to do my best to give a general overview of the basics of photography, and my suggestions when taking a picture.

Terminology: [general tip regarding the term], {more advanced tip regarding the term}

Shutter/Shutter speed: The shutter is what opens and closes to allow light to hit the sensor/film. The Shutter speed is the speed in which it does so. For entry level DSLR’s the range is usually BULB (meaning as long as you hold the button the shutter will stay open, until your battery dies) through to it’s fastest 1/4000 (meaning 1/4000th of a second). Compact camera’s (point and shoots) range typically ~10″ (the shutter will stay open for 10 seconds) to a maximum of ~1/2000. [For freeze frame action use a fast shutter speed, for motion blur/ soft water/ streaks of lights from passing cars/etc use slow shutter speeds, ie 1/4]

Aperture: Is sn opening that controls the amount of light let into the camera. (As the aperture is inside the lens, aperture is lens dependent). The bigger the aperture the more the shutter opens, allowing more light through the lens, allowing a faster shutter speed if needed. Consequently the bigger the aperture, the shallower the depth of field. (see below) When shooting at as big of an aperture as possible, this is refered to as shooting wide open. [For more flattering portraits shoot with a large aperture, for all objects in the photo to be in sharp focus use a small aperture]. {Note sharpness is also related to aperture, where in most cases shooting wide open is not the sharpest. Most lenses have a sweet spot, a small range of apertures that produce the sharpest image.}

F Stop (F:): Is simply a measure of aperture. This is what is displayed on lens, or on the camera. F stop is inversly proportional to the aperture, meaning a small F stop indicates a large aperture, and a large F stop indicates a small aperture. So a small F: results in small depth of field, and vice versa. A lens with a really small F: (large aperture, F: < 3) is refered to as fast glass, and usually expensive. [For more flattering portraits shoot with a small F:, for all objects in the photo to be in sharp focus use a large F:]

Focal length: Is a measure of angle of view, commonly refered to as zoom. A super wide angle may have a focal length of ~10mm, where as a super telephoto may have a focal length of ~500mm. A focal length of 10mm has an angle of view of 102.4 degrees (meaning it can see clearly everything within 102.4 degrees from the lens) and a focal length of 500mm has an angle of view of 5 degrees. [For landscapes or architecture use wide angles, for wildlife use telephotos. When shooting portraits it it always more flattering to use telephoto’s over wide angles] {Focal length also affects depth of field, the further you zoom in the shallower the depth of field, Also standing back and zooming in increases the size of whats in the background as well. This technique works well in portraits to “clean up” the background if so desired}

Focal Length

Focal Length

Focal length 2

Focal length: top 32mm, bottom 500mm

focal length comparison- From Canon EOS sys brochure

focal length comparison- From Canon EOS sys brochure

ISO: Is a measure of the cameras sensitivity to light. ISO comes from Internation Organization for Standardization, (in Swedish, which this organization is, the order ISO makes sense). The higher the ISO the more sensitive the cameras sensor is to detect light, which can allow for higher shutter speeds, or compensate for lower F stops. The trade off is with higher ISO the image quality goes down. A low ISO today is 100, a high ISO is 800 or 1600; with extreme highs of 25,600 on cameras like the Canon EOS 5D II. ISO is also spoken of in stops, with an increse of 1 stop being a doubling of ISO. (So 2 stops higher then ISO 100 is ISO 400). With an increase of 1 ISO stop you can double your shutter speed to get the same exposure. [For general use, use as low of an ISO as possible, for low light situations like concerts or indoors use higher ISO’s]. {When shooting night photos where you will need to use shutter speeds slower then 30″, to figure out how long you will need to expose the sensor put your ISO fairly high, then take the light meter ratings suggestion of shutter speed and double it everytime you cut you ISO in half. Ie/ if at ISO 800 you get a reading of 30″, when you shoot at ISO 100 (which you should be for nice night photos) your shutter should be open for 4 mins.}

Exposure: Is just the light hitting the sensor (or film), which results in the bightness of an image, ideally having a nice balance between shawdows and highlights. An image that is overexposed will be too bright with the subject bleeding (fading) into the highlights, an image that is underexposed will be too dark and often apear dull  and lose the wow factor.

MP’s: or Mega Pixels, is the number of pixels, in millions, that make up a cameras sensor. The more MPs a camera has the larger the file size and in theory the more detail and higher quality in the image.¬† The number of MPs is not related to physical size of the sensor which is an important factor to image quality. The more MP’s on a physically small sensor increases the PDR (Pixel density ratio). The higher the PDR the lower the image quality. Which means if the MP race continues and camera makers keep craming more and more pixels onto small sensors all that will happen is you will get larger file sizes and lower quality. [Turning down the MPs of your camera will not increase their size and therefore not increase quality, so you may as well keep shooting your point and shoot at full 12 mp or whatever insane number they are at these days]

Depth of field: This is the range of distance from the sensor that in an image is in focus. Shallow depth of field is where only a small portion of picture is in focus the rest is out of focus (out of focus region is refered to as Bokeh). A large depth of field is where the entire image is in focus. To decrease the depth of field you can zoom in, use a smaller F stop, and/or get closer to the subject. [For portraits it is more flattering to have a shallow depth of field]

Zoom: Is a rather pointless term used in point and shoot cameras, where you take the focal length at the wide side and divide by the focal length at the tele side. So a 10X zoom could be either 1mm-10mm (An incredibly wide and impractical range) or 10mm-100mm (A great standard range). [When choosing a compact camera look for optical zoom over digital zoom]