Step 2: Perform Quick Assessment Of Image

If you are serious about making the best possible image from a digital photo, you must have an overall editing strategy, you must use the appropriate tools correctly, and you must perform the steps in the proper order. A quick assessment of the original digital photo is the best way to determine your editing strategy.

■ Determine if the image uses 8-bits per channel or more by choosing Image ^ Mode to get the menu shown in Figure 8.3. Because a check mark is next to 16Bits/Channel, we know that the image is a 48-bit image (16-bits per each of the red, green, and blue channels).

When performing basic tonal and color corrections, each application of the Levels, Curves, Hue/ Saturation, and Color Balance commands further degrades the image (although it may look better). To give users the flexibility of changing the settings for these commands without having to reapply them, which would further degrade the image, Photoshop 7 allows the creation of adjustment layers for each of these commands. At any time during the edit process, you can click an adjustment layer and adjust the settings without further degrading the image. However, these useful adjustment layers cannot be used on images that have more than 8-bits per channel.

So, the good news about the eagle image is that it has 65,536 tonal values per color channel, which results in a higher quality image than a 16-bit per channel image, which has only 256 tonal values per color channel. The bad news is that we cannot use adjustment layers until the mode is changed to 8-bits per channel.

If the goal were to end up with the best possible image, you would apply Levels and Curves to the image first, change mode to 8-bits per channel, and then complete the editing process by using Adjustment layers when possible. Instead, for this example, change the mode to 8-bits per channel to start with and use adjustment layers throughout the

Bitmap Grayscale

Duotone Indexed Color i/ RGB Color CMYK Color Lab Color Multichannel

8 Bits/Channel i/ 16 Bits/Channel

Color Table,,,

Assign Profile... Convert to Profile.

process so that you have the benefit of being able to tweak the image at any time by using adjustment layers. After you have gained experience with this image, go back and edit it in 16-bit mode and see if you can improve the final results by using the higher bit mode — just make sure you get the settings correct on the first pass and do not apply the commands more than once.

■ Choose Image >- Adjustments >- Levels (Ctrl+L) to get the Levels dialog box shown in Figure 8.4.At a glance you can see that the image lacks values on the right side of the histogram, which indicates the image lacks highlights. Yet, looking at the left side of the histogram, you can see that there are plenty of values in the shadow area; hence, the reason the image looks dark and flat. Next, take a quick look at each of the channels in the Levels dialog box by pressing Ctrl+1, Ctrl+2, and Ctrl+3. Alternatively, you can click in the Channel box in the Levels dialog box and click each channel from the pop-up menu. As you switch between channels, you'll notice the right ends of each channel histogram ends at a different value. This tells you a colorcast likely needs to be removed.

■ Click Cancel to close the Levels dialog box.

■ Take one more look at the image to determine any other important issues that you need to keep in mind while editing. Because of what you learned from Levels, you know that the tonal range can be spread out considerably, which helps improve the contrast, but such spreading of the tonal range may cause posterization. The eagle could be improved dramatically if there were more contrast in the dark feathers. Finally, you want to avoid increasing contrast in the white feathers to the point where you get posterization, as they already appear to have some blown-out highlights that are hidden by low contrast level of the image.

With this insight about the image, our editing strategy is:

1. Adjust overall tonal range by using Levels.

2. Remove color cast by using Levels if it remains after using eyedropper tools in Levels.

3. Increase contrast in dark feathers by using a Curves and a layer mask.

4. Adjust color by using Hue/Saturation.

5. Make final adjustments by using previously created adjustment layers.

6. Duplicate image, flatten image, and sharpen image.

0 0

Post a comment