21) Make your adjustments the same way you normally would, but keep in mind that you can return to them later if need.

22) Click “OK” and a new entry in the Layers palette will be created for the Adjustment Layer as shown in figure 22.

23) You can change the overall effect of an Adjustment Layer by changing its opacity. This option will be found at the top right of the Layers palette. Opacity defaults to 100% but you can lower it to any desired level.

24) Click on the “Ctrl” key and move the slider as much as you need. Another way is to type the number to whatever you want. If you lower opacity to 0, it will have no effect on the image as shown in figure 23.

25) It may the case that you have more Adjustment Layers stacked. Photoshop will combine them all together by default, applying them all at once rather than one at a time. When you work in 16-bit mode, the image’s data loss is lower. Adjustment Layers can help prevent loss in the first place, as data loss from rounding is minimized {see figure 24}.

26) You may not want always to affect both the brightness and the color saturation of a picture. This happens because an image using the RGB color scheme does not separate luminance from hue (color) when saving the information. In cases when you want to correct a picture taken in a foggy day you will appreciate this. But there may be times when you might only want to correct exposure and not to modify the saturation, s it would lead to un-welcomed effects on the image. In this case, you should convert your image type from RGB to Lab Color Mode. This mode also uses three color channels, but uses them in a different way: the “L” channel will isolate the luminance (both the darkness and the brightness), while the remaining two channels will contain color information. Convert you image to Lab Mode by selecting Image > Mode > Lab Color as shown in figure 25 .