Don’t understand digital photography vocabulary ? Below articles helps to eliminate confusion.
4K video has normally a resolution of (4096 x 2160 ) approximately 4 full HD video added together (1920 x 1080). Some cameras record even higher resolution.
AA filter or Low pass filter (Olpf)
AA filter(anti-aliasing) is used in front of the image sensor in most modern digital cameras to eliminate unwanted patterns called moire. (This often occurs when we make pictures of something with repetitive patterns like factory buildings for example) Some newest cameras with high pixel count(Nikon d7100, Nikon d800E, Nikon d810, Fuji X cameras) omit AA filter completely, which results in slightly sharper images.
Adapter is a device which is used for connecting other two pieces of equipment which otherwise cannot be connected.
Aps-C sensor format
Aps-C format or Dx in Nikon is a sensor size of 22.5*15mm or around, from 22.2*14.9mm up to 23.5*15.7mm. The bigger size is more used by Nikon, Sony and Fujifilm (crop factor 1.5x), the smaller size is more used by Canon(crop factor 1.6x).
Aps-H sensor format
Discontinued format between Aps-C (22.5*15mm) and Full frame (36*24mm). The Aps-H format sensor size is 28.7mm*19.1mm. Earlier Canon 1 series cameras has this format. Crop factor is 1.3x (Middle of the road between Full frame and Aps-C).
Aperture – photograpy terms
The adjustable hole on the lens which controls the amount of light enter to the camera sensor. Aperture controls depth of field. (DOF) Smaller apertures allows bigger depth of field(preferred for landscapes or macro photography), bigger apertures allows shallower depth of field (preferred for portraits of wildlife).
Artifact – photograpy terms
Barrel distortion – photograpy terms
Most lenses has some kinds of distortion. The two basic types are the barrel and pincushion distortion. We spoke about barrel distortion when the picture looks like a barrel, the otherwise vertical lines going outwards from the picture. It is a very common type of distortion among wide angle or fisheye lenses.
Back light – photograpy terms
When the sun shine behind the subject. It can be used for artistic reasons, but for most cases better to avoid. Most lenses loses contrast and has different types of artifacts caused by direct light in the frame.
BIF – photograpy terms
BIF often used in birding forums, which refers to Bird in flight pictures.
Bokeh – photograpy terms
Out of focus blur on the picture. The word has a Japan origin refers to blur. Different lenses produce different looking out of focus areas. The bokeh is perhaps most important at portraits, where the soft background makes the photo more artistic.
Blown out Burned out
In bright circumstances the camera cannot capture the highest part of the scene, instead makes it white without any details. These parts are blown out.
In camera histogram the graph touches the right side of the image.
We speak about flash or exposure bracketing. The bracketing means we make several, usually 2 or 3 images with different exposures. One darker, one brighter, or one darker, a middle, and one brighter images. The camera has a dedicated function for it where we can set the number of images captured and the exposure differences between the different shots. See stops below for better understanding.
When we use continuous shooting the camera RAM stores images, which otherwise wouldn’t be recorded in so short time. The camera buffer defines how many pictures we can make in a short time using continuous shooting. After the buffer is filled the camera slows down and cannot record images so quickly. Manufacturers usually specify the camera how many frames can record in the buffer. Usually much few number of Raw images, than jpgs. A buffer can be for example 18 Raw images, 70jpg, 170 smaller size jpg etc. Continuous shooting means the camera has a maximum frame rate of 6 fps, and we use this feature in action photography. For example the bird flying towards us and we want to make as much frames as we can possibly make. We start to shoot when we see the bird in the desired place and we can make pictures until the buffer slows down the process. Usually not many pictures great if the subject is quickly moving, but 1-2 frames can be really good. If our camera buffer is 18 Raw images, and we have a 6 frame per second frame rate, this means we can make pictures app. during 3 seconds, after the camera will slows down. A buffer less than several seconds is not so useful.
Longer exposure than 30 seconds. In Dslr cameras it is only possible in Manual mode. When we starts the shot we press the button and holds it until the end of the shot. Some kind of remote release is needed if we don’t want to push the shutter for hours. It is very useful in Night Astro photography. A good tripod is a must.
Charge-coupled device. The CCD makes electronic image out of the optical signal. The first digital imaging sensor was a CCD type sensor. Most compact cameras has a CCD sensor.
The abbreviation means Complementary metal oxide semiconductor.
CMOS is the sensor type used in almost all digital cameras today. In the beginning it was used by Canon in Dslr models.
Crop factor is refers to the sensor size of the digital camera. The 1x crop factor is refers to the Full frame camera with a 36*24mm sensor. The Aps-C cameras has a crop factor of 1.6x or 1.5x depends on the sensor size. Micro 4/3 cameras has a crop factor of 2.
Dynamic range – Photography terms
Dynamic range refers to the light and dark parts tonal range on the same photographs. Usually digital cameras unable to present the whole scene as we see it with our eyes, there are two things can happen:
1.Blow out the lightest parts of the image, no details, just white.
2.The picture will be too dark, dark parts simply goes black, without details. Higher dynamic range cameras can capture more tonal range.
DOF – Photography terms
Depth of field refers to the sharp zone in front of and behind the focusing point. The DOF depends on several factors: lens focal length, distance of the subject, the lens maximum aperture (brightness). If we want to blur the background, which is preferred for portraits for example, the best combination is the longest focal length, closest subject distance, and the brightest lens. This create the biggest blur. On the other hand if we want everything in focus, we use the widest lens, the smallest aperture, and longest subject distance.
Dslr camera – Photography terms
Digital single lens reflex camera. The difference compare to compact cameras that the Dslr cameras has a mirror and a pentaprism or pentamirror in cheaper models. These two elements lead to the light to the whole at the upper part of the camera, thus allowing us to see a real picture. It is like a periscope. Normally we compose the picture in the viewfinder where we see the real scene. Newer Dslr cameras has a Live view mode which means we can use the back LCD to compose the pictures like in compact cameras.
EV – Photography terms
EV stands for exposure value. Not so easy to explain. It refers to light levels. A normal scene has approximately 12EV dynamic range. See the explanation below at stops.
EVF – photograpy terms
EVF refers to eletronic view finder. The electronic viewfinder is like the LCD screen at the back of compact cameras, but at eye level, like optical viewfinders. Some compact cameras has electronic viewfinders and nowadays it is also popular among MILC cameras as well. The drawback of the EVF is energy consumption and lower image quality compare to optical finders. The important parameters of the EVF is the refresh rate and the resolution. Obviously higher refresh rates and higher resolution is preferred to have better more recent picture. Basically EVF is the image that the sensor see, and send to the viewfinder, this is the problem because the sensor has high limitation compare to human vision (dynamic range, colours, sharpness, refresh rate). Some newer higher end MILC cameras has better viewfinder with higher resolution and better refresh rates than the usual olds ones.
EXIF – photograpy terms
The EXIF is a standard information of the picture in the picture file. The EXIF usually shows the shutter speed, used aperture, camera model, lens focal length, ISO value etc.
Evaluative or Matrix metering
This is the metering method I use the most, because it is the most reliable. Metering in digital cameras to determine the exposure level similar to 18% grey. This is how most scene looks like, except very bright scenes like beach or snow, or dark scenes like forest. Here at these scenes we use exposure compensation. + compensation means brighter (beach, snow) – compensation means darker (forest).
If I want to simplify this, it is the brightness of the image. The correct exposure means the camera makes an image as bright as 18% grey. If the picture is darker we spoke about underexposure, if the picture is lighter we speak about overexposure. Thing called Correct exposure is not exist, you determine how you want your picture to look. If you want your picture to be brighter, for example a wedding photo, we spoke about high key photography, if you want you pictures to be darker we spoke about low key photography, both can be used for artistic purposes.
Digital cameras calculate brightness of the scene as of the whole scene would be 18% grey colour bright. But some scenes are brighter or darker. For example snow without trees are brighter or beach as well, forest are darker. In these cases we uses exposure compensation to make the picture as we see. If the scene is brighter we use +exposure compensation, if the scene is darker(for example dark forest) we use -values. Usually +-1EV enough for most scenes, but modern cameras are capable to make +-5EV exposure compensation.
Flash synch speed – Photography terms
Most cameras has a maximum flash synch speed of 1/250s with in built flashes. What does this means? If you want to use the flash in bright sunlight for portraits to fill shadow areas the camera won’t use higher shutter speeds than 1/250s. If there is a lot of light around the camera will stop down your lens for f/16 or smaller apertures that the shutter speed won’t be faster than 1/250s or overexpose the image. External flashes can have a faster synch speed 1/1000 or faster. This function called high synch speed which is very useful if you want to photography wildlife action or shallow depth of field portraits.
Flare – Photography terms
Direct light source can produce bright or colored artifacts on the picture. On some lenses the contrast level is reduced if we shoot towards the sun. Good lenses has special coatings on the lens to reduce flare. Other thing is helps is the lens hood, which blocks sidelights to the lens.
Fringing or Purple fringing – Photography terms
Some lenses produce purple color in transition area in high contrast scenes, for example tree branches against the sun. The amount of purple zone can be measured, and the lens can be categorized based on the value measured. Good lenses produce low levels of purple fringing, and some cameras are able to correct this flaw automatically.
F-stops, stops in photography
This can be confusing because the stops has multiple meaning in photography. Usually one stop means half or double quantity of light. If we have the same lens, and wants half quantity of light, we stop down the lens with one stop. If we want 1/4th quantity of light we stop down the lens with 2 stops. How we do that? We make the aperture or iris of the lens smaller. There is a number attached to this to show the value. Between these values (apertures) the difference is 1 f/stop. If the number after f/ or 1: is bigger than the aperture(the hole on the lens) is smaller. If the number is smaller the lens allows more light in. The numbers goes like this: f/1(brightest), f/1.4, f/2, f/2.8, f/4, f/5.6, f/8, f/11, f/16 f/22. Between each aperture and the neighboring aperture the difference is double or half quantity of light. This means if you stop down the lens(makes the hole on the lens smaller) from f/5.6 to f/8, we let half quantity light in. This also means half time shutter speed as well. For example we have a shutter speed of 1/100s at f5.6 we will have 1/50s at f/8. You can observe that for 1 stop difference, the factor between the numbers are 1.4x. 5.6*1.4=8, 2*1.4=2.8 etc.
The below pictures show the same scene with different exposure(brightness) levels. The first underexposed image is underexposed with 1 stops (exposure compensation -1, the middle picture was made with 0 exposure compensation (1 stops brighter), the third brightest picture was made with an exposure compensation of +1 (overexposed by 1 stops, 2 stops brighter than the first darkest picture) )
1 Stop means double or half quantity of light. If I compare the darker scene to the brighter, the brighter obviously have double quantity of light, if there is one stop difference. If we speak about shutter speeds, darkest picture has double shutter speed compare to the 1 stop brighter, the brighter has half shutter speed compare to the brightest. The darkest has 1/4 times shutter speed compare to the brightest, the brightest has 4 times shutter speed compare to the darkest. There are fractional stops like 1/3 or 1/2 stops are also existing. Recent cameras usually uses 1/3 stops setup, with an option to change to 1/2-s.
The f-stop can be calculated by focal length/lens entrance pupil (effective aperture). I give some examples. For example we have a lens with 400mm focal length and 72mm diameter hole(max aperture), the f-number is 400/72=5,56 app 5.6 or f/5.6. If we have an 50mm focal length lens with a hole of 27mm diameter, the f-number is 50/27.7=1.8, if we have a 17mm focal length lens with a max hole diameter of 4.85mm the f/stop is 17/4.85=3.5, if the hole is 6.07mm 17/6.07=2.8. On the other hand we want to know which diameter needed for a 600mm f/5 lens, we can calculate it like this: 600/x=5, x=600/5=120mm. If we want to know the lens hole size on the 135 f/3.5 lens, it is 135/x=3.5, the x aperture diameter is 135/3.5=38.57mm it is not the filter size but the whole in the aperture.
Full frame – Photography terms
Earlier the most used format was the 36x24m film. Today Full frame refers to cameras with 36x24mm sensor, or lenses used for these cameras.
Glass – Photography terms
The glass refers to lenses in Dslr photography. Generally lenses has more impact on image quality than camera bodies. Among photographers are quite common they call lenses simply glass, like bikers call the motorcycles iron.
Gradual density filters or grads widely used among landscape photographers. The gradual density filter is half dark half transparent grey filters. Most of them unlike other filters in photography are rectangular and has not threaded on the lens. These filters are useful to darken the sky to have a better blue color on the picture.
HDR – Photography terms
The abbreviation of high dynamic range. As explained before the digital camera cannot capture the whole range of light levels. To overcome this we can make more photos with different brightness levels to include the whole range of the scene on different pictures. After we blend the different pictures on one photograph arranged together by a computer program, or some cameras can make it automatically as well in HDR function.
HDSLR – Photography terms
A HDSLR is a DSLR camera which can record High definition video. Basically all Dslr available today. A term HDSLR only used by Nikon.
Histogram – Photography terms
The histogram (top right) shows the different light levels of the given picture. The darkest parts at left, the brightest at right. In the middle area we call midtones. The peak or valley graph shows how many pixel you have at the given tone. The brightest parts we call highlights, the darkest parts are usually the shadows. If most of the graph in the left side of the picture, there is two options: we make a pic of an all dark something, with no light, or we seriously underexposed our image. If the whole graph is on the right side of the histogram either we make a photo of a bride with white skin on a white horse or we seriously overexposed our image. How to make a correct exposure? If the graph touches the right side of the histogram we blown out our picture. If it touches the left side we have black parts on the image or we make something black. The usual method is to expose as much bright as possible without touching the right side of the histogram. But sometimes the scene has too wide dynamic range, the image remain too dark, here I sometimes choose to blow out some parts of the image, to save other parts to be better (lighter). If we make a landscape for example blow out parts looks strange especially if they cover huge area in the frame, for portraits or for example wildlife shots can be ok.
The more correct histogram shows the red green and blue channels separately. Why ? Because we can blow out the red channel for example without recognizing it from the single histogram.
Hot shoe – Photography terms
Hot shoe is a small metal part at the top of the cameras for connect external flash units. Few compact cameras has a hot shoe, it is more common between Dslr cameras.
IQ – Photography terms
This refers to image quality.
ISO – Photography terms
Light sensitivity similar to ASA in films. In darker situation we use higher ISO to avoid blurred pictures.
Keystoning – Photography terms
When we make photos of high buildings with wide angle lenses, typically these lenses has some distortion, which results not parallel edges. Tilt-shift lenses can eliminate this problem.
Mirrorless interchangeable lens camera. This terms refers to wide range of cameras with different parameters. Some of these cameras has essentially the same sensor, this way very good picture quality like Dslr cameras.
MFT or Micro Four Thirds system
Micro Four Thirds camera system is used a sensor size of 17.3*13mm, which is half long compare to the Full frame 36x24mm, little smaller than Dx or Aps-C (23.5*15.6mm or 22.3*14.9mm). The Manufacturers who make Micro 4/3 cameras are Olympus and Panasonic.
Moire – Photography terms
The digital photograph is consists of squares called pixels. When we make a photo of a subject with a repeating pattern like factory buildings for example, other types of repeating patterns can appear on the photo. For example the building has a horizontal and vertical pattern, and the moire can be slantwise. This pattern is called moire. To eliminate this most digital cameras has an AA filter or Low pass filter in front of the image sensor. Newer cameras with high pixel count omit this filter which results in sharper images. The difference is more visible in bigger sizes.
The ND or Natural density filters are simple gray filters to reduce light quantity. Theses filters are mostly used by landscape photographer to make long shutter speeds in daylight. These helps to create some dreamy movement on the picture especially at water surfaces or waterfalls.
Out of focus.
Pincushion distortion – photograpy terms
We spoke about pincushion distortion when the otherwise parallel lines bow inward directions. It is more common in longer lenses, or longer focal lengths, while barrel distortion is more common in wide angle lenses. One zoom lens can have two types of distortion at different focal lengths.
A person who spends too much time in front of the computer to analyze picture sharpness, noise levels of lenses or cameras, by looking 100% magnified pictures.
Rule of thirds
If you compose the picture, usually not put the subject in the middle, because it looks boring. Mostly put the subject at 1/3rd of the frame, this rule is applicable horizontally and vertically as well. For example if you make a landscape it is boring to put the horizont at half height, better to put at bottom or top third of the picture.
The resolution refers to the amount of detail that a lens can capture or for example an LCD monitor can show. The resolution of a picture usually described with the amount of pixels. For example 6000*4000 pixel is 24 Megapixel. In lenses the resolution is measured how many distinct black and white pair lines the lens can identify. They measure lens resolution per image height at the center mid-frame and at the corners. Usually the center is the sharpest, and the corners are the less sharp.
The sensor is the most important part of the Dslr camera. The price of the camera mostly depend on the sensor. Larger sensors which usually provides much better image quality are more expensive. The sensor is the one part of the camera which defines the possible best image quality. Other parts of the camera are mostly plastic, glass and metal. The sensor makes digital image from the optical signal. The two most used types of sensor today is the CCD and CMOS. The CMOS is the preferred today.
|Nikon lenses||Canon lenses||Lens reviews||Reviews|
In Spot metering the camera only measure the 3-5% center part of the image. It is the easiest to make strange shots with spot metering if we meter for a dark or bright object. I use mostly evaluative or matrix metering instead, because this way I avoid completely useless shots. The shot metering is good when you can control the situation (photographing a still subject), and can make the shot once more if you not satisfied.
It is not a blonde girl, but a rule of a shutter speed. In bright sunlight you need a 1/100th of a second shutter speed at ISO100 at the aperture of f/16, this is where the name derived from.
The sweet spot is the lens’s best sharpest aperture. It is f/5.6 for most lenses, f/8 for most longer lenses (longer than 300mm), very few lenses sharpest at f/4.
Teleconverter – photograpy terms
The teleconverter is usually a small lens which we attach between the main lens and the camera body. The teleconverter is like a magnifying glass, makes our lens longer. The usual types are the 1.4x, 1.7x 2x, and 3x teleconverters.
The 1.4x teleconverter makes the lens 1,4x longer, means the 200mm lens will be 200*1.4= 280mm, the 2x converter makes the lens 2x longer 200mm will be 400mm and so on. Teleconverters are works best with prime lenses of 135mm and longer. Also works well with very good zoom lenses. The most useful teleconverter is the 1.4x type, the 2x teleconverter degredes image quality too much for most lenses, only works well with the really best prime or zoom telephoto lenses. Teleconverters are most popular among birders and wildlife photographers where the most reach is needed.
The Canon lenses excellent ultrasonic focusing system is called USM (ultrasonic motor). There are two types: ring type USM and micro USM motors. The better is the ring type USM motor used in high end lenses, this focusing system is almost silent, very quick and precise. Micromotor USM is only occur in two lenses as far as I know: The Canon 50mm f/1.4 and the Canon 70-300mm f/4-5.6 USM. Micromotor USM is not as good and fast as the ring-type USM motor.
Vignetting or light falloff
The side of the pictures are usually darker than the center of the frame. The difference is measurable. The vignetting is more pronounced on Full frame cameras.
VR is vibration reduction or image stabilizer in Nikon lenses. The stabilizer helps to create sharp images in low light when images without the stabilizer would be blurred.
White balance or WB
The camera’s ability to correct unwanted color casts in different lighting situations such as daylight tungsten fluorescent light.