When I first upgraded to my DSLR digicam and started the usage of it substantially, I discovered myself facing an entire kind of problems, and for many of them, I couldn?T locate easy solutions on-line or in any of my starting photography books. I realized a lot later that some of these problems were so basic and fundamental that experts who had been taking pictures for a long term had probably forgotten that they had ever no longer acknowledged a way to do such things.
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| Sunset in Cancun, Mexico. Sunsets may be complicated to get the right exposure. |
This is the second article in an occasional series aimed at beginners called “Things Experts Forgot to Tell You” or “Things that You Forgot you had to Learn.” (The first article is Why Won’t My Lens Focus?) Maybe you’ve just purchased your first DSLR camera or perhaps you’ve had one sitting around for awhile that you’ve been meaning to start using. The next big steps are getting out there, figuring out what you and your camera are capable of, and learning where to get answers to your questions. While the first two steps are up to you, this series is an attempt to briefly cover some of the questions that might not have yet occurred to you to ask.
What is ?Correct? And ?Creative? Exposure?
Photography books, blogs, and manuals are full of information about exposure, but initially, I had a very hard time sorting out what they all were talking about. Some speak of ‘making an exposure’ when they simply mean ‘taking a photograph.’ Others talk about ‘exposing for a specific element in the picture’ or choosing the ‘correct’ or ‘creative’ exposure.
Exposure is calculated by your camera. Each camera has a sensor that analyzes the scene in the viewfinder and chooses a combination of shutter speed, aperture (f-stop), and ISO to make what it deems a ‘correct’ exposure: where the colors and highlights and lowlights seem to accurately represent the scene being photographed. There are many different ways that this determination is made. Many point and shoot and DSLR cameras have scene modes, such as portrait, macro, landscape, action, nighttime, etc. that use different settings to match what the camera thinks works best for that style of picture. Even when shooting in program, aperture-priority, or shutter-priority modes, there are different ways that the camera can calculate exposure. (On a Canon these metering modes are known as evaluative (or matrix), partial, spot, and center-weighted average. For the majority of scenes, evaluative mode will suit you just fine, but more on that later.) There is more than one ‘correct exposure,’ however, and these are known as equivalent exposures.
This is easier to explain with an example. Let’s say that I am shooting in Program Mode with evaluative metering, where I set the ISO and the camera determines both the shutter speed and the aperture. I’m outside on a sunny day, so I’ll leave the ISO at 100 (the lowest or native value on my camera), and the camera suggests an exposure of 1/200 at f/9. If I twirl the dial to adjust those values, I will get pairs that represent the equivalent exposures – the same amount and quality of light being recorded by the sensor. Examples here include, say 1/60 at f/16 or 1/500 at f/5.6. I can choose any of these pairs of values, and they will represent what the camera has determined to be the correct exposure.
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| Equivalent exposures with variable shutter and aperture (all ISO one hundred) |
In the series of images above, each of the four combinations of settings are equivalent exposures, but the pictures themselves are different. Because the ISO was set at 100, each change in the aperture value required an equal and opposite change in the shutter speed. So, as the aperture got narrower, the shutter speeds got longer. The ‘correct’ exposure is the one that you, the photographer, decide upon. If you wanted the blurred background of the upper left picture, then that would be the correct exposure for you. If you wanted the sharper detail of the lower right picture, then that would be the correct exposure for you. (You would also want to be sure to use a tripod, like I did, in that case, as it is difficult to maintain a sharp image while hand-holding at a longer shutter speed like that one. See How to Maximize your Tripod for more details.)
Creative exposure is anytime that you, the photographer, override the camera’s suggestion. You can choose a creative exposure in aperture priority, shutter priority, or manual mode, by adjusting the shutter, aperture, or ISO to values other than those suggested by the camera. You can choose a creative exposure in program mode by using exposure compensation to tell the camera to deliberately over- or underexpose the shot. The images below were shot using exposure compensation to under- and overexpose the picture by one stop each.
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| A contrast between a deliberately underexposed (left) and overexposed (right) version of the same concern. |
If you need a darker, moodier shot, you will choose an publicity this is decrease than the one counseled through your camera, which could underexpose the image and make it darker. Likewise, if you desired a brilliant shot with a white heritage, you will choose an exposure this is higher than the only recommended by your camera, which would overexpose the image and make it lighter.
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| This high key product shot changed into intentionally overexposed (according to the camera's publicity reading) which will carry the history to natural white and emphasize the bottle. |
Scotch Product Photography via Archaeofrog on Flickr
When you camera determines its correct exposure, it is looking to make all the tones average out to what is known as medium (18%) gray. This means that if you take a picture that is mostly bright, white snow, the camera is going to choose an exposure that darkens your snow to a dull gray instead of the bright white your eyes saw. Similarly, if you take a picture of your friend’s large black dog, the camera is going to choose an exposure that lightens the dog to a duller gray than your eyes saw. These are both situations where the ‘correct’ exposure as determined by your camera is unlikely to match the exposure that you are looking for. This leads us to the second question:
Is there an smooth manner to manipulate what the camera is exposing for?
Photographers, books, and publications also regularly discuss with publicity in a greater precise sense, the concept that you need to ?Disclose for? A specific element in a photograph. This receives at the problem discussed above. If you are taking a image of a black dog, you likely want that black dog (the problem) to be efficiently exposed, instead of became a lighter gray canine. Likewise, if you are taking a photograph of a palm tree at sundown, you may want the digicam to show for the sundown, turning the tree into a black silhouette (like inside the photo on the pinnacle), rather than attempt to reveal for each the sunset and tree, which might dim the sundown colorings and convey pointless element to the tree.
There are distinctive metering strategies that your camera can use, which I mentioned in advance: evaluative (or matrix), partial, spot, and center-weighted. Evaluative and center-weighted do not forget the complete body when calculating the publicity, partial takes into account simplest the middle section of the body, and notice takes into account only a completely small location at the center of the body. All of these area more emphasis on regardless of the lighting fixtures is in the middle of the frame (with partial and see except for the entirety else). If what you need to be exposed effectively isn't always in the center of the frame, inclusive of the sunset and clouds, then you'll need to lock inside the exposure.
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| The top shot chose an exposure of 1/60 @ f/6.3 based on the darkness of the bison. |
The bottom shot chose an exposure of 1/320 @ f/7.1 based on the lighter grass.
Bison and Baby via Archaeofrog on Flickr
You may additionally need your manual to locate the AE lock (automated publicity lock) button on your DSLR. (On my Canon T1i it's far indicated by way of the * symbol.) The AE lock button tells the digital camera to calculate its exposure analyzing based on regardless of the digicam is pointed at whilst you press the AE lock button, in preference to on some thing it's far pointed at when you click on the shutter. With the instance of the bison above, after I took the primary picture, the digicam used the darkish bison on the center of the photograph to calculate the publicity cost, which led to a very vibrant and washed out historical past. For the second photograph, I moved the digital camera to factor at an empty location of grass right next to the bison, pushed the AE lock button to set the publicity for the grass, and then recomposed for the bison and took the photo. Now the grass is properly uncovered, and each bison extra correctly reflect their colors.
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| The bottom shot turned into uncovered for the sky and displays greater vibrant hues inside the sunset. |
Sunset over Lake Mendota by Archaeofrog on Flickr
For deep, bright sunset colors and dark silhouettes, the trick is to expose for the sky (not the clouds). Set up your shot, then point the camera at the sky, press the AE lock button, recompose, and take your shot. You can see the difference in the two images above. For the second, the camera chose a slightly faster shutter speed to underexpose the image (relative to the first), which resulted in the deeper colors. Another option for sunsets is to bracket your shots and take both over- and underexposed versions.
What is Exposure Bracketing?
Bracketing is the technique of taking a couple of image throughout a range of exposures, and there are a few reasons you may need to consider bracketing positive shots.
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| Three photographs of plants in a window, bracketed at -1 (left), 0 (center), and +1 (right) |
One cause that photographers choose to bracket photographs is for later use in HDR (high dynamic variety) images. Our eyes can see a more variety of mild than our digital camera ? We will look outdoor a vivid, daylight hours window and spot each the brilliant gadgets outdoor and the dimmer objects interior. If you try to take a photo of a bright window, however, you'll have a tough time and could ought to either take a shot with the bright items out of doors successfully exposed (with a darkened interior) or with the dimmer interior successfully exposed (and a blown out or perhaps all white window). With HDR pictures, you would take a sequence of or more pictures at exclusive exposures (right here, one exposed for outdoor and one uncovered for inside) and then combine them into one photograph later using HDR software program. Some photographers are essential of the ?Overdone HDR? Fashion that has been digitally manipulated to have unreal colorings and tones.
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| A contrast of distinct ways of processing the three photographs above using HDR |
Another cause photographers pick to bracket pictures is when there's rapidly converting mild. I regularly use exposure bracketing when I am capturing sunsets or the moon rising. The high-quality and coloration of the light is frequently converting unexpectedly, and publicity bracketing allows me to seize a range of photos (lighter and darker) and decide later, at the laptop, which ones are my preferred exposures for every situation. Compare the 3 variations of the moon upward thrust shot under. Some would possibly pick the darkish tones of the underexposed version (left), while others might opt for the brighter blues and bigger glow of the overexposed version (proper).
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| Three photographs of the moon rising over the Madison capitol, bracketed at -1 (left), 0 (center), and +1 (right) |
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| Scale for exposure compensation, displaying the set up to bracket 3 pictures at plus-and-minus one forestall |
Many DSLR cameras come up with the choice of mechanically bracketing your pictures. With my Canon T1i, if I select the publicity reimbursement option (the scale that goes from plus-or-minus 2), then I can spin the dial, which selects for three different factors along the scale. The default is targeted on zero and then the alternative flow in tandem to plus-and-minus the identical value. I can also use the arrow keys to move all three pictures up or down the dimensions. If I am bracketing pictures, I often pick out for plus-and-minus 1, centered on 0. Then, when I am equipped to take the photo, I preserve the shutter down lengthy enough for it to hearth off three pictures: the first might be the correct publicity, the second one underexposed by using one prevent, and the 1/3 overexposed by means of one prevent. For the great effects, in particular in case you need to combine the photographs later, it's miles excellent to apply a tripod and self-timer. (For more details, examine How to Maximize your Tripod.)
Exposure Summary
When I first began seriously taking images with my DSLR, I observed exposure to be a specially overwhelming idea. What I turned into lacking become the big picture: that publicity is actually the camera figuring out which settings it thinks will make the great image, based at the to be had light, and that there are exclusive combinations of settings so that it will provide you with the identical (equivalent) exposures.
You are smarter than your digicam (even in case you doubt that reality), and there are times while you and your digicam are going to have a difference of opinion approximately the exposure you are looking for. This is while it can be beneficial to use publicity reimbursement to deliberately over- or underexpose your photo to gain the look you need. Or you could use the AE Lock to ?Tell? The digicam what you've got determined is essential for the exposure calculation. Or you can bracket your shot to seize more than one unique exposures and choose the excellent later (or integrate them in submit-processing). Controlling exposure to healthy your functions will make a large distinction on your photography.
Want more posts geared toward beginners? Click 'For Beginners' up at the top or try the rest of our series, Camera Settings and Strategies:
- More about Exposure: how to fix common exposure problems in your photography
- Aperture and the F/Stop Conundrum
- What an Aperture of F/1.8 Can Do for You
- What an Aperture of F/22 Can Do for You
- The Middle Range Apertures: f/8 - f/11
- Shutter Speed: an overview
Want to research more?Boost Your Photography: Learn Your DSLR is now available from Amazon. Get the most out of your digital camera with practical advice approximately the technical and creative elements of DSLR images a good way to have you taking lovely photos right away.
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