Some bright spark had the idea of making a glossary of digital photography terms. And of giving me the project.

The idea is to explain in layman's terms what our weird words mean. Layman's terms? I'm the man for the job. But the problem with being a layman is that I don't know much.

So I need your help. Check out the list I have so far. What mistakes have I made? What needs to be added?

Think of this as your charitable contribution to the cause. Not tax deductible. I don't think.

Brightness
The amount of light your image is putting out, or reflecting. The overall lightness of your piccie. A well-exposed photo has good brightness, without being overexposed. Also, think of the color in your image as being broken down into three components – brightness, saturation and hue.



Burning and Dodging
Lingo from the old darkroom days. Dodge means to make a portion of your shot brighter. Burn means to make a portion of your image darker. Can be applied to Shadows, midtones and highlights.



Contrast
Having distinct bright and dark portions in your image. As opposed to a more uniform, or grey, lightness. The brighter the brights and the darker the darks, the more contrast you have. Contrast is generally considered a good thing, makes your shot “pop.”



Crop
Literally, cut off a part of your image. Imagine taking a pair of scissors and snipping off parts of a photo print. Usually done to help the composition or to remove distracting elements.



Exposure
How much light has been allowed into the camera to make your image. Underexposed means you let in too little light and everything’s too dark. Overexposed means you let in too much light and everything’s too bright. Digital cameras don’t have as much dynamic range as film so are more sensitive to over- and under-exposure.




Dynamic Range
Your camera’s ability to handle a wide range of light, from bright to dark, in the same image. Digital cameras have a narrow dynamic range, far more narrow than film used to make prints. That is to say, they have a hard time handling extremes of darkness and brightness in the same picture. For example, bright sunlight with a deep, dark shadow.



Panorama
Several shots arranged to give a larger perspective than is possible with a single image. Usually the photographer pans their camera along the horizon, taking images that overlap one another. The shots are arranged side-by-side in the post-production process.



Red Eye
What happens when a flash is at the same angle and close to your camera lens when you take someone’s picture. Their eyes seem red in the image. Can be fixed in post production. Or by using a flash that’s not as close to the lens.



Sharpen
Make the edges of things in an image more distinct. When you sharpen a photo, you make the focus seem clearer, or sharper. You also see detail more clearly. This is a post-production technique.



Anti-aliasing
Removing the tiny jagged edges in the curved lines of your digital images. Your digital photo is made of millions of tiny pixels. They’re square. Squares don’t make good curves. Corners stick out. Anti-aliasing smoothes out these corners so curves look even, not jagged. Cindy Crawford thanks you.



Color profile
Computers are dumb. They need to be told how to handle color. The instructions are called a “color profile.” Because life is complicated, there is more than one kind of color profile in the world. Each has its own uses. It’s a good thing to know what color profile your camera and your software are using, when you post-process your images.



Feathering
Making a sharp edge seem softer in your image. Usually used when making a selection in post-production. You often soften its edge so your selection blends-in more naturally with the background.



Gamut
The number of colors your eye can make out is your eye’s color gamut. Gamut = range. Your eye is the top dog when it comes to color gamut. Your camera, your computer monitor, your software, your printer – they all have their own color gamut, or range. And all of them are more limited than your eye’s. All hail the human eye.



Gaussian Blur
Makes your image blurrier, or out-of-focus, usually for dramatic effect. Imagine holding a piece of gauze in front of your eyes. It makes what you’re looking at a little blurry. If it doesn’t, go see your eye doctor. You can get the same effect with computer software in post-production. Most programs have a filter called Gaussian blur, that allow you to control the amount of blur. By the way, Gaussian has nothing to do with gauze – it’s actually a math thing. And therefore incomprehensible.



Masking
Literally, putting a mask over a part of your image. It’s a technique used in post-production. When you want to change only a part of your image, you “mask” the parts you want to protect. That way your changes are only applied to the parts you don’t mask.



RAW
A way of saving your photo so that the camera does as little processing to the image as possible, before storing it. This gives you a lot of flexibility in post-production to change your photo’s exposure, saturation, sharpness, contrast and more. Normally, your digital camera’s processor will control all of this to make your picture look good. Expensive digital SLR’s give you the option to tell your camera not to.



Resolution
The number of tiny little pixels that make up your digital photo. The more pixels you have in a given space, the more detail you have. Detail is considered a good thing. A lot of people use the words resolution and detail interchangeably.



Unsharp mask
This is the post processing filter you use to make your digital photo sharper. It’s also a perfect example of making things more confusing than they need to be. You’d think they’d call it the “sharpen” filter. But nooooo.



Histogram
A handy graph that shows you how the light in your image is distributed, from light to dark. It will also show you if you’ve exceeded your image’s dynamic range. Digital SLR’s can show you a histogram for each photo, so you can adjust your exposure while you’re shooting. Good photo editing software does too, so you can better control your photo’s brightness and contrast.



Layers
A magical way to edit your photograph without changing the original image. In a darkroom, when you make a change, you can only do it to the original photo you’re printing. But with some photo editing software, you can make an almost unlimited number of copies of your image. They’re all stacked on top of each other, in “layers”. And each layer has a single change made to it, like contrast or saturation. When viewed from above, the image you see combines all the changes from each layer. Even better, you can “turn off” a single layer, and see what it looks like to remove one of your changes. And you can “mask” portions of each layer. It’s a wondrous thing.



Sharp/Soft
Jargon for in-focus or out-of-focus. Sharp means in focus, all the lines and the detail are sharp. Soft means the opposite, everything looks soft, no sharp edges or detail. You can improve your piccie’s sharpness with “unsharp mask” or make it softer with “Gaussian blur.”



Hot
Jargon of over-exposed. A portion of your piccie is “hot” if it’s so bright it’s white and you can’t see any detail in it. This the worst sin you can commit – you cannot recover detail from a hot, or overexposed, portion of your image. This is where “RAW” and “histograms” come to your rescue.



Bokeh
Blur. When the subject of your piccie is sharp and in focus, and everything else is out of focus, the out-of-focus stuff is called bokeh. It happens when you set your lens to have a narrow “depth-of-field”. It’s a great way to draw attention to your subject. Bokeh is a Japanese word that means fool. As in “to fool”. I hope.



Shadows
The darkest parts of your image. Specifically, the darkest 30% of your shot. The relationship between your shadows, midtones and highlights constitutes the contrast of your photo.



Midtones
The tones that fall between shadows and highlights in your image. No kidding, huh? Roughly, the lightness that makes up the middle 30% - 70% of your image. The relationship between your shadows, midtones and highlights constitutes the contrast of your photo.



Highlights
The brightest, lightest 30% of your image. The relationship between your shadows, midtones and highlights constitutes the contrast of your photo.



Composition
It’s what you decide to include inside the frame of your picture. Composition is the order in which those things appear, their relationship to each other. The human eye finds some visual relationships more pleasing and interesting than others. Check out the “golden ratio” – it’s fascinating stuff.



Post-production or Post
Work you do to your image after it leaves the camera. With film, it’s what happens in the darkroom. With digital images, you use software in your computer. Photoshop is the current king of the post-production hill. Also know as post-processing.



Selection
A tool in your photo editing software that lets you outline, or “select”, a specific part of your image. You can then copy that selection and put it onto another photograph as a layer. For example, you can select a bone from one photograph, and add it to another photograph that shows a happy dog. Or you can make changes only to your selection, leaving the rest of your shot unchanged.



Filter
A way to add effects to your photograph. With SLR cameras you can put a filter in front of the lens to get an effect. The people who make photo editing software have taken the same concept and gone wild with it. You can make your photo blurry, make it sharp, distort it, all sorts of whacky things.



Saturation/Desaturation
The intensity of the colors in your image. More intense color = more saturation. If you desaturate your image, you are removing the color from it. A black and white image is completely desaturated.



Depth of Field
The amount of your image that is in focus. All lenses are capable of putting everything in focus. But you can make some lenses put only a small part of your overall image in focus. This is called a narrow depth of field. You need a lens that has a long focal length and a wide aperture to get the narrowest depth of field.
Here’s the technical language for it: “The amount of distance between the nearest and farthest objects that appear in acceptably sharp focus in your photograph. Depth of field depends on the size of the aperture, the distance of the camera from the subject, and the focal length of the lens. The bigger the aperture, the greater the depth of field.”



Tone/Tonal Values
This can mean a couple of things. It can mean the color cast of your image – warm tones mean there’s more red in the image, cold tones mean there’s more blue. Check out the definitions for color temperature and white balance. There’s a second meaning, too. Tone can also mean the relative amounts of lightness and darkness of your piccie – the feel of it.



Golden Ratio
This is literally a mathematical formula that describes shapes that the human eye finds pleasing. For example, the shape of Cindy Crawford’s face matches the golden ratio. Lucky her. You can use the golden ratio to organize the elements of your photograph into a pleasing assemblage. Literally, the golden ratio is 1.61803, or the ratio of a diagonal of a pentagon to its side. Huh?



Warm/Cold
An image is considered warm if it tends towards being red. And cold if it tends towards being blue. It all has to do with color temperature and white balance.



Color Temperature
This is how the color spectrum in light is measured. It’s the actual temperature of different colors in light, as measured in degrees Kelvin. Red and blue are at opposite ends of the spectrum. Red is considered warm and blue is considered cold. The higher the color temperature, the more light is being put out.



White Balance.
A setting in your camera, or in your photo editing software, that makes sure white is displayed as white. When you have white set properly, all other colors in the spectrum will also be correctly displayed. If your image is too warm or too cold, chances are your white balance is wrong.



Color Cast
When the colors in your image don’t look like they should, when they have a tint. If your grass seems too red, for example, then you have a warm or red color cast. Usually this happens when your camera has the wrong white balance.

OK, that's the list so far.

Any suggestions?

Wow. What a great start!

My thoughts (as unqualified as I am...)

Change "arranged side by side" to "stitched together" in the Panorama one.

Red Eye: the flash is bouncing off the retina, reflecting back red.

Sharpen is all good, but you should say that sharpening can only do so much, and won't make a blurry photo in focus.

Feathering, change "naturally" to "gradually"

Maybe mention adjustment layers in the layers definition? Or make it a separate entry?


Depth of Field: that whole "bigger the aperture" thing always confuses me, at first. That's because the number's bigger, but the aperture is actually smaller. Anyone else get confused by that?

Originally Posted by DavidTO Depth of Field: that whole "bigger the aperture" thing always confuses me, at first. That's because the number's bigger, but the aperture is actually smaller. Anyone else get confused by that?

Depth of Field
The amount of your image that is in focus. All lenses are capable of putting everything in focus. But you can make some lenses put only a small part of your overall image in focus. This is called a narrow depth of field. You need a lens that has a long focal length and a wide aperture to get the narrowest depth of field.
Here’s the technical language for it: “The amount of distance between the nearest and farthest objects that appear in acceptably sharp focus in your photograph. Depth of field depends on the size of the aperture, the distance of the camera from the subject, and the focal length of the lens. A small aperture like f/16 will have a wider depth of field than a large aperture such as f/2.8 which has a very narrow depth of field.

Originally Posted by Shay Stephens Depth of Field The amount of your image that is in focus. All lenses are capable of putting everything in focus. But you can make some lenses put only a small part of your overall image in focus. This is called a narrow depth of field. You need a lens that has a long focal length and a wide aperture to get the narrowest depth of field. Here’s the technical language for it: “The amount of distance between the nearest and farthest objects that appear in acceptably sharp focus in your photograph. Depth of field depends on the size of the aperture, the distance of the camera from the subject, and the focal length of the lens. A small aperture like f/16 will have a wider depth of field than a large aperture such as f/2.8 which has a very narrow depth of field.

Works for me!

Cool stuff, thanks guys.

David, I avoided "stitch" as that adds one more definition to the list. But I guess it needs to be there anyway.

Shay, would be it be more accurate to say "deeper depth of field" rather than "wider depth of field"? And "shallow" rather than "narrow"?

Probably tomato toemahtoh ;-)

Whatever floats the boat hehehe

Originally Posted by wxwax Cool stuff, thanks guys. David, I avoided "stitch" as that adds one more definition to the list. But I guess it needs to be there anyway. Shay, would be it be more accurate to say "deeper depth of field" rather than "wider depth of field"? And "shallow" rather than "narrow"?

Originally Posted by wxwax Cool stuff, thanks guys. David, I avoided "stitch" as that adds one more definition to the list. But I guess it needs to be there anyway.

How about "join"? Side by side doesn't mean to me that they've become one image, they could still be separate.

Originally Posted by Shay Stephens Depth of Field The amount of your image that is in focus. All lenses are capable of putting everything in focus. But you can make some lenses put only a small part of your overall image in focus. This is called a narrow depth of field. You need a lens that has a long focal length and a wide aperture to get the narrowest depth of field. Here’s the technical language for it: “The amount of distance between the nearest and farthest objects that appear in acceptably sharp focus in your photograph. Depth of field depends on the size of the aperture, the distance of the camera from the subject, and the focal length of the lens. A small aperture like f/16 will have a wider depth of field than a large aperture such as f/2.8 which has a very narrow depth of field.

I don't want to ruffle feathers here, but, the relationship between focal length and DOF gets really confusing.

Shay is correct that shooters tend to think of long lenses as having shallow DOF and wide lenses as having much more DOF. I use them myself with this intention frequently.

BUT - Technically, the focal length of a lens has NOTHING TO DO with Depth of Field IF the subjects are the same size in the image plane. That means a wide angle lens must be much closer to a subject than a telephoto lens for the image sizes to be the same size at the image plane - IF the image sizes are different, then we're comparing apples to oranges.

The easiest reference I found for my assertion that focal length does not affect DOF is here in wikipedia - http://en.wikipedia.org/wiki/Depth_o..._field_formula

But I can also quote it from the Time-Life series on Photography, and Gilles Martin's tome about Macrophotography.

Depth of Field is strictly a function of aperature and distance from the image plane for a given film format.

Long focal length lenses TEND to be used for things far away, short focal length wide angle lenses TEND to be used for things much closer with a much wider perspective than the narrow view of a long lens. This is why we think of wide angle lenses as having more DOF than telephotos.

Try it - Shoot a series of images with a 24, 50, 100 and 200mm lenses with a constant subject size on the image plane and check the DOF - you will find my statement is correct - Focal length does not affect DOF.

Flame suit on

One other thing - bokeh means 'fuzzy' according to Mike Johnston who was one of the first to use the term BOKEH in English language publications ( http://www.luminous-landscape.com/co...04-04-04.shtml ) , or 'blur' according to wikipedia again - http://en.wikipedia.org/wiki/Bokeh. Maybe a Japaneese speaker can chime in here for a better term.

I'm so glad you are doing this rather than me waxy

In 10 words or less?




Any definition we give here has to be truly simplified. I think we're explaining the concept, not the details. Bokeh could be as simple as "selective blur in an image."

Was the word "mask" included, didn't notice, but it seems to be used many ways and I have no idea what is being talked about most of the time?

I have many more things I don't know, but only think of them when they come up. "Mask" came up recently, as a response and suggestion to me.

I just can't grasp that word.

Plus many other words that have to do with layers.

Plus "blending"..........???

ginger, all I can think of now. I am very jargon impaired.

Yeah, Ginger, mask is in there. I know, it's a long list, and not yet alphabetized.

Layers is in there too. Not sure about blending. How d'you mean?

it is a great list..but for my 2 centsa worth..I would prefer to have a list of abbreviations included..as I can find a dictionary to give me a def..however trying to decipher what some of you are talking about when YOU use abbreviations truly baffles me at times.....

Thanks just my $.02 worth

Originally Posted by wxwax OK, that's the list so far. Any suggestions?

how about definitions for vignetting, chromatic aberation (?)

thx for doing this

Originally Posted by Frog Lady how about definitions for vignetting, chromatic aberation (?) thx for doing this

Ah, good ones, thanks.

Originally Posted by Art Scott it is a great list..but for my 2 centsa worth..I would prefer to have a list of abbreviations included..as I can find a dictionary to give me a def..however trying to decipher what some of you are talking about when YOU use abbreviations truly baffles me at times..... Thanks just my $.02 worth

Hmmm, I could include abbreviations, but that wouldn't help you find the meaning of one. That would have to be a different list.

How about including the abbreviation in the definition

Depth of field (DOF)
Chromatic aberration (CA)
etc...

Originally Posted by wxwax Hmmm, I could include abbreviations, but that wouldn't help you find the meaning of one. That would have to be a different list.

Purple Fringing

Vignetting

Originally Posted by David_S85 Purple Fringing

See Chromatic Aberration.