The Manual tab allows the photographer to correct for their particular lens profile. This is used when Lightroom 3 cannot find the profile of the lens used to capture the selected image, or for photographers who choose to make lens corrections without using automated functions. The manual tab allows for various transform, crop, vignetting and chromatic aberration corrections (Figure 6).
The image in Figure 7 was shot at a bad angle and with a zoom lens that also introduced perspective distortions. The automatic Profile functions did not find the particular lens used to capture this image. Therefore, a manual adjustment is needed. Select the manual tab brings up all the correction options as shown in Figure 6. The image needs vertical, horizontal, distortion and some rotation changes. When the slider bar is clicked, a grid will overlay the image allowing for adjustments that are more accurate. Running through each slider and making changes corrects for the lens and perspective distortions, as shown in figure 8. Figure 9 shows the comparison between the uncorrected and corrected images.