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Imaging Tutorial #5: AiPICT v8 and AiPICX v8

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Fixing UnderExposure: No Flash, No Problem!

While on vacation, you arrive at a memorable tourist spot. It is a bright, sunny day. No need for flash, right? You ask a fellow tourist to take your picture, and did not bother to check the photo. Back at your hotel, you review your photos and wish you had set the automatic flash settings. No problem, we can fix that.

Note: If your display is not gamma-corrected, subtle changes may not be visible.

Lighten midtones and shadows by adjusting the Highlights slider; here it is set to "200" - just at the point where the froth from the water falls begins to disappear. The shadows are further lightened adjusting Gamma slider to "125". Combine some of the original highlights and midtones by setting Mask control to "15". Voila! Per se, we can consider the image correction done. Our subject's face is now visible; the trees and rock formations in the background have also come to life. Can it still be improved? Yes.

By default the Saturation levels method is selected and automatically set with optimized settings based on a histogram analysis of the photo. Though acceptable, let us tweak the settings further.

In actual view, original JPEG artifacts have become quite visible. The Highlights slider is adjusted to "200". The Gamma slider is adjusted to "110" to add a bit more color to midtones. Since we're on a roll, let us tweak the photo further.

By the default, automatic contrast levels are detected. Tweak the Shadows slider to "10". Bump up the midtones a bit, by setting Gamma slider to "120". The noise evident in the shadows can also be removed; let us mop up.

The default settings are fine. However, we can tweak the values further. Here, we adjust the Filter slider to "114". Last but not the least, a bit of sharpening seems to be in order.

Overall sharpness is enhanced via Unsharp Mask method.

 BEFORE  AFTER

Summary: In this lesson, we tackled the exposure problem first, then made adjustments to color saturation. Minor adjustments to contrast and midtones were then tweaked. Finally, we cleaned the noise hidden in the shadows and sharpened the image. The methods applied are not exclusive; you can try other methods and sequences that may better suit you. Experiment! You can always "undo" changes :)

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