Level of difficulty: beginners
Is image processing cheating? No.
- Digital images are the result of processing the data generated from millions of red, blue and green pixels in the light sensor. Processing is actually a necessity in order for a digital photo to look realistic. Of course, processing can also be use to create an emotional response in the viewer such as ephemeral, moody, dramatic or old fashioned.
- Over-processing produces a garish and unnatural appearance causing the viewer to ask “Is that what it really looked like?
- Correct processing causes the viewer to say “Wow”.
- Over 99% of all professional’s digital images are processed.
What is image processing?
- the adjustment/manipulation of the data generated by the digital sensor when it is exposed to light. Some frequently adjusted properites of an image are contrast, color hue, saturation, brightness of highlights, darkness of shadows, white balance, sharpness, etc).
- Processing is done in-camera immediately after the photo is taken to create jpg images.
- If you do not direct the adjustments, you will have to accept a lot of guess work by your camera and its image editing software.
There are three main categories of image processing: in camera, raw converter and “post processing”. I will primarily address in-camera and raw converter processing today. Post-processing with full editing software, such as Photoshop will be covered in a future post.
In camera processing: Within all digital cameras, there is a tiny computer processor. Unless a camera is set to record a “camera raw” file format, this processor modifies/adjusts the data generated by the digital sensor immediately after a photo is taken. If you are recording images in the jpg file format (image file name ends in .jpg), then you are using processed images. Your images are being processed within your camera. This processing is required to create a jpg file format image. If you do not adjust the camera’s default settings for creating a jpg image, then your camera has to make a lot of guesses about the lighting conditions present and about how you want your image to look. If you like the appearance of all your jpg photos already, then there is no reason to make any change. However, if some of your images look dull, flat or washed-out, then you will benefit from learning how to control at least some of your camera’s processing. It’s not as difficult as it sounds. In fact the first stage is very easy.
How do I begin processing without being overwhelmed? Do just a little at a time. If possible, take at least 20 minutes every day or two to learn something new about the editing programs that you have (an editing program comes with every digital camera). Then take at least 10 minutes to experiment with one of your images with the information that you learned.
How to begin controlling the in-camera processing?
1) For in-camera processing of jpg images, begin using you camera’s program modes for landscape, portrait, night scenes, etc (Different manufacturers give these different names, but common names are picture styles or creative program modes). They are usually accessed either via a button on the back of the camera or with a wheel that has tiny pictures on it). These will allow you to use presets that your camera came with, so that you do not need to make all the changes by yourself initially.
- “Standard” (auto) programs are for general use. They usually increase contrast mildly and color vividness (saturation) and sharpness moderately.
- The landscape setting (usually with a picture of a mountain) will make blues (sky) and greens (grass and tree leaves) more vivid (more saturated), strongly increase sharpness for greater detail and use a small aperture width for maximal depth of focus.
- Portrait mode will adjust color for better skin tones, add little or no sharpness (for smooth skin) and use a medium width aperture so that the background is blurred (helping to keep one’s attention on the person).
- Close up mode (usually with a picture of a flower) increases color saturation, increases sharpness and uses a wide aperture for fast shutter speed and blurring of foreground and background.
- Other specific program modes or picture styles, such as night scenes or action/sports, make their own distinctive adjustments. Letting your camera know what type of picture you are taking, will help it to produce a more pleasing image.
2) The reason to take greater control over the in-camera processing is to decrease the amount of guess work that your camera has to do about the style, composition and lighting of the image that you took. Also your camera will not have to guess about your personal preferences for your images (For instance, I like more contrast, saturation and sharpness than average). The goal is to create more realistic or evocative images, although it will allow you to have unusual or weird effects if you choose. Generally we want images that appear realistic to the viewer.
- White balance: First, I recommend that you learn to set the white balance. I covered this in detail in my last post entitled “Photography: White Balance Essentials”. If you are not familiar with white balance, please check it out.
- Contrast, saturation and sharpness: Find your camera’s settings for these image characteristics. Usually they will be in the recording menu or the menu for “functions” or custom picture styles. (Often there is a button on the back of the camera that gets you quickly to these settings. (Check your camera’s instruction manual).There, you can individually adjust contrast, color saturation, sharpness, color tone and perhaps some additional properties (depending upon your particular camera). Begin by adjusting just one of these characteristics at a time. (The changes that you will make now will not affect your camera’s settings for the preset picture styles and creative program modes (landscape, portrait, close up, etc that I mentioned with in-camera processing-part 1, above).
- Setting contrast: Low contrast gives a smooth, delicate, dreamy or flat appearance. High contrast increases depth of field, detail and texture. It also can give a more dramatic appearance to images. Take pictures of the same thing with different settings for contrast. Start with the lowest amount of contrast offered and work up to the maximal setting. Compare the images to see which you like best. Make a note of it. (The very highest and lowest settings are likely to make it look weird, but sometimes you may want to make your images weird). You probably will like a different amount of contrast for landscapes than for portraits, than for night scenes, etc. You can add that information later. It’s a very good idea to keep a record or journal of the settings that you like. (In the past, whenever I have not written it down immediately, I have forgotten the result and have to do it all again.)
- Saturation (vividness of colors): Low saturation tends to give calm, delicate of dreamy feel to the images. Moderate saturation gives vivid colors and a dramatic feeling. High saturation tends to look garish and definitely unnatural. Take a photo of something at each of the settings offered by your camera from the lowest to highest option. Again compare the pictures to see which settings you like best for this particular type of photo and write it down. You can do this with other types of photos later to see whether you like different t settings for them.
- Sharpening: Generally, low sharpening gives a smooth look to skin in portraits, less apparent texture and depth of field and helps with a calm or delicate feel. High amounts of sharpening bring out texture and depth of field. It is often used for landscapes or images with lots of detail (like leaves of a tree). But high levels of sharpening will ruin most images, so be judicious. High levels of sharpening create lots of artifacts (tiny circles called halos at the edges of things). Halo artifacts give a very unnatural appearance and cannot be removed once a jpg image is recorded. A very common error is to apply too much sharpening.
Images recorded in a jpg file format loose data each time they are opened. However images with a tiff file format are stable and do not loose information. It’s best to convert your jpg images to tiff images as soon as they are into your computer. (If you click on the “File” menu and click “Save as”, you can change the file format to end with the letters .tiff. )
Raw converter processing is primarily for images recorded with a “camera raw” file format (CR2 for Canon, NEF for Nikon and other manufacturers have their own initials for this type of file). “Raw files” contain only the unprocessed data collected from the sensor when it was exposed to light (It is no more complicated than that). The advantage of using raw files are that they are durable. They do not loose information with repeated opening. Any editing changes applied to a raw file can be erased or replaced at any time. The adjustments do not alter the original image file. In this way, raw files are analogous to negatives in the film days of old.
- All cameras that offer the option of a raw file format come with the software to edit those images (technically called a raw converter). Other programs, such as Photoshop and Photoshop Elements also contain raw converters.
- Keeping with my recommendation that processing be learned a little at a time, start with adjusting two image characteristics: white balance and sharpness.
- White balance: Even if you set the white balance prior to taking your photo, the color may not look just right to you when it is opened in the raw converter software. (It’s easiest to fix color if something in your photo is , or at least is supposed to be, pure white. Find the drop down menu for white balance (usually toward the top of the screen or toolbar) and click on each option successively (sunny, shade, cloudy, etc) to see which gives the correct color. If none of these options gives a good resut, look for the eyedropper (white balance) tool and click on something that is supposed to be white. You may need to click on a couple of different places on the white object to get the best result. If nothing in your image is white, most programs allow you to click on something that is supposed to be neutral gray to determine white balance (It does not have to actually be neutral gray, just something that is supoosed to look newtral gray.
- Sharpening: All raw images, require some sharpening to look good. This type of sharpening is safe for your image. For good results, try just a small amount of sharpening. If your program offers you a sharpening scale from neg 4 to +4, try +1 or +2. Check your image on the screen at 100% magnification to see if you like the result. If using Photoshop Elements raw converter, get to sharpening by clicking on the little tab with the triangle on it (just above white balance adjustmejnt). Then try amount 25 to 40, radius 1 and detail 25 (for images with lots of detail, like landscapes, movethe detail slider up to 50). You do not need to do all the sharpening now. More sharpening is usually added later, after further editing with a full feature program such as Photoshop, Photoshop Elements or Lightroom. That type of sharpening is destructive and needs to be done as the very last step of processing.
- Gradually add additional settings after becoming comfortable with these two settings. Adding a little at a time, but frequently is the a great way to learn processing.
Post-processing with full edit software will be covered in a future post.
Comments, suggestions (and criticisms) are welcome.
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