What Do You Do Once You Get Your Files?

This is primarily written for my own clients, but the information is general enough for anyone who finds herself in possession of a huge number of image files and wonders what to do now.

Viewing the Files

To browse a large number of files, there are a few options.

An Image for All Seasons

On your CD, you’ll find a variety of kinds of images. This is a quick guide to what’s what.

Images that come directly off the digital camera are named P0number.JPG. This is a raw or unprocessed image, and you’ll have a lot of them. These are like the negatives you get back when having traditional pictures developed (except the colors are not backwards), in that you need them to make other things. When you have pictures developed, the negative is used to make a print and the technician will adjust the colors and brightness and contrast when doing so. Likewise, to make a good final image out of a raw image, these kind of adjustments need to be made. This is discussed in more detail below.

Any image that’s been produced by working on the original raw image will be named by adding onto the file name. For example, if P0001234.JPG is the original image, then P0001234-1.PSD and P0001234-2-mini.jpg are files produced by working on that original. You can always reference the original involved by looking at the first part of the file name.

A file meant for you to look at on screen, a polished or final or processed image, will usually be called something like P0001234-1.jpg, and be sized to fit on a typical screen, and compressed using JPEG to download quickly or store compactly on your disks.

A file having mini in the name is a miniature version of another file, small and highly compressed. These are poor quality and designed to download quickly and fit with many others on the display.

A file having a .PSD extension is a PhotoShop native file. It is the actual work, and by saving it this way someone can contine to work on the image. It contains more information than a regular image file, such as multiple layers and details about which parts were made lighter or darker, so this can be updated or tried again. These files are huge.

A file with a .PNG extension is also a regular image file, but unlike a .JPG is lossless.

Using Polished Images

On Screen

Generally, you will use these to send people via email, post on your website, put in documents, or show in your on-screen photo album. The screen-sized JPEG files are meant for this.

Printing

The JPEG files designed for use on-screen should not be printed, as they don’t contain high-enough quality. Yet you still want the cropping, color adjustment, and other changes that have been made so you don’t want to use the original raw image, either. Instead, print the .PSD file. This contains more pixels since it has not been shrunk to fit the screen, and doesn’t suffer the artifacts of JPEG compression. Sometimes, though, you may find a .JPG or .PNG file that is higher-resolution than the screen-sized image—this will print better than the lower-resolution image.

If you have a photo-quality printer, you can print out pictures yourself. Alternatively, you could send the file to a professional. There are a number of places that will give you lots of sample 4x6 prints for free. I have a list of them on my web site. Getting good 8x10 prints can require a bit of skill and a few hundred dollars in more advanced software.

Processing a Raw Image

Here’s how to take a raw image and make it suitable for presentation. If you don’t want to do this yourself, I can do it (only for pictures I’ve taken for you) for fifty cents each.

Step 1. Choose Your Tool

Thumbs Plus can itself view and do adjustments on a picture, in addition to organizing them. This is certainly handy, if you’re using Thumbs to catalog and view them in the first place.

However, Paint Shop Pro, which is also included on the CD I sent you, can do a lot more. There are other low-end image-editing programs out there, and you might already have one or more as they are often bundled with things like scanners.

The big guns though is Adobe PhotoShop. That’s what I use. However, it costs a great deal, and takes a while to learn how to use well.

Step 2. Choose Your File

You’ll have a hundred or more photos from a session, and you need a lot fewer than that to fill your frames. So be choosy. There will sometimes be a group of very similar photos taken one right after another, but the poses are a little different, or one is brigher and one darker, or other variations. These were done so you could look back later and see what you liked best.

For this tutorial, you should be starting with the raw image. In general, never process a .JPG file other than the original raw image that came off the camera. This will have a name like P0001234.JPG (always 8 characters, with nothing else after it) and have a resolution of about 1800x1200.

Step 3. Crop

The simplest yet most significant thing you can do to improve a photo is to crop it. Cut out unwanted things along the edges and focus in on the subject.

The adjustment steps listed later are all the same kinds of things that a technician does when making prints from negatives. However, you generally don’t get cropping done on snapshots. But a professional photographer or artist will crop, and that’s one reason they turn out better than simple snapshots.

Step 4. Overall Brightness

The picture might be too dark or too light. This is the next thing to adjust.

Often, a snapshot taken indoors with a flash will be too high in contrast. Besides increasing the overall brightness, lower the contrast to bring details out of the murk. For pictures like this, the general rule is to lower the contrast until just before it starts to look like the air itself is hazy. Simultaniously, increase the brightness. This combination will serve to brighten shadows, since lowering contrast pulls both ends toward the middle (darkens bright areas and lightens dark areas).

This picture below was processed by pressing C in Thumbs Plus, then using the brightness/contrast page in the resulting dialog box.

Brightness and Contrast, and in general, “Levels” or “Curves”, control the range of pixel intensity values in the file. You should be able to see the lightest parts of the image without solid white spots, and see the darkest parts of the image without solid black regions.

If I’m just making quick work of a whole bunch of images, I’ll quickly crop and adjust brightness/contrast using Thumbs Plus, before showing the directory to anyone else. However, as a first step to a full treatment to make a polished image, I’ll use the PhotoShop “Levels” control.

Here you see the result of moving the right slider left to 201 and the middle slider left to 1.83. This graph lets me see that the “meat” of the image is clustered far to the left. Generally, it’s simple to find when there is unused latitude on either side and push the outside sliders in, with far less error and guessing than with a “contrast” control. Sliding the center arrow does a terrific job of increasing or decreasing the “exposure”, meaning I like the results even though it might not be scientifically correct. The results are better than the one above.

This kind of difficult exposure is probably best corrected using “Curves” dialog box in PhotoShop, though I am not very good with it. Ideally though it would be the best tool for bringing out the zones of interest without over-brightening the white table clothes.

For correctly-exposed photographs using natural light, you don’t have the same contrast problems as you do with flash photos. Below, the effect of moving the right Input Level in to 215 is shown only on the right-hand side of the photo. As-is, the picture was just fine. Visibly, the effect is subtle: I get a little more contrast and see brighter whites. But more significantly, we will use the entire range available going into further manipulation.

Pictures taken under controlled conditions or natural light look just fine to begin with, but careful adjustment can make the most out of them. For difficult photos, a simple slider or two can be like the difference between night and day, making an ususable picture passable under the circumstances.

Step 5. Sharpen

The file that comes off the camera is, to use the vulgar term, blurry. This is because of the way the high-resolution CCD sensors work. I’ve found that the built-in sharpening on the camera doesn’t work well enough, as the correct setting varies from photo to photo. So rather than apply a fix on top of a fix, it’s better to turn it off altogether and do it yourself from scratch.

The image editing tools have a variety of sharpening filters, with names such as Sharpen and Sharpen More. The simplest thing is to try each one and see which one looks the best.

A fancier scheme is called the Unsharp Mask algorithm, and it works in a somewhat different way. More importantly, it has three knobs to adjust exactly what it does, so you can tune it to be “just right” for the situation. Note that Thumbs Plus has Unsharp Mask listed on the menu, but this is not a real Unsharp Mask! It’s completely misnamed, and is in fact one of the several available simple sharpening filters.

Step 6. Color Correction

Digital photos, I’ve found, need less color correction than negatives. But still, a picture may have a bit of a color cast to it, and this is the time to correct it.

Step 7. Resample

If you are going to use the image on-screen, reduce its size to 800x600, 640x480, or whatnot.

If you are going to print the image, don’t resample it at all! Keep all the pixels you can, as the printer will want them all and still wish for more.

Step 8. Save the File

If you are going to be emailing this to someone or posting on a website, save it as JPEG with fairly aggressive compression. If you don’t need to make the file small, but will not work on the file again (remember, never re-work a JPEG file), use JPEG with gentle compression (higher quality). A medium-quality JPEG looks just fine as long as you don’t zoom in.

If you are going to print the image, or plan to contnue working on it later, save as a PNG file. PNG is lossless, but still a standard format, that any other tool can read. If you have used advanced techniques such as layers, save it as the native format of the editor, since that’s the only way to preserve this extra information.

Advanced Manipulation

Many photos can be improved upon. A common example is the use of “doging” and “burning”. In the days before digital image manipulation, photographers would commonly improve the apparance when making a print by holding their hands or small tools in the beam of light, “doging” to reduce the exposure of selected parts or “burning” to increase the exposure of selected parts.

In digital image manipulation, the names are still used, and the concept of lightening or darkening selected parts of an image is still an important part of getting the best image. For example, dark clothing might appear totally blacked out instead of having visible detail. This needs to be lightened.

Often, the subject and the background will not match in exposure. In traditional photography, reflectors and very carfully calibrated fill lights are needed to get a proper match. But if you adjust the brightness of the subject after the fact, you have much more flexibility when taking the picture, and need much less lighting equiptment to take such a picture.

In more extreme cases, it’s possible to fix lighting problems. In the example below, lightening the foreground and darkening the background was not enough, as the features on the face were still shadowed.

Besides simply lightening it, the picture needed to be carefully brushed with light to bring out details, and some detail of the corner of the eye was actually hand painted.

An artist can also remove unwanted details that intrude upon the scene, change colors, or even combine multiple pictures to produce special effects.

A common example is removing blemishes from skin. Makeup covers them fairly well by matching the color, but makeup won’t stop a zit from casting a shadow. Fixing this is usually very simple, because the detail is small.

The normal process of sharpening the original image can be modified to produce an “airbrused look” instead. Do this by only sharpening high-contrast edges on the face.

For pictures I’ve taken, I charge $50/hour for this kind of work.


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