Common Problems

Common Problems

Q1:	How do I improve an overexposed photo?
A1:	Add an adjustment layer by going to Layer> New Adjustment Layer and choose Levels. Click OK in the Levels dialog without making any changes. Then in the Layers palette, change the blend mode of the Levels layer from Normal to Multiply. If necessary, you can duplicate the Levels layer to darken the effect by pressing Command-J (PC: Control-J). You can also duplicate the entire Background layer, or make a feathered selection and duplicate just one area, and then change the mode to Multiply.
Q2:	How do I improve an underexposed photo?
A2:	Add an Adjustment layer by going to Layer>New Adjustment Layer and choosing Levels. Click OK in the Levels dialog without making any changes. Then in the Layers palette, change the blend mode of the Levels layer from Normal to Screen. If necessary, you can duplicate the Levels layer to add to the effect. You can also duplicate the entire Background layer, or make a feathered selection and duplicate just one area, and then change the mode to Screen.
Q3:	How do I improve the focus of a photo? POLLY REINCHELD
A3:	There are a number of sharpening filters (Filter>Sharpen) as well as the Sharpen tool, but in general, the Unsharp Mask filter works best. If the problem appears to be a slight motion blur, try Smart Sharpen, as that filter lets you choose the type of blur to fix.
Q4:	How do I remove (fix) red eye?
A4:	First, try the Red Eye tool (it's found under the Spot Healing Brush in the Toolbox) because that is its functionclick on the red area in your image and the color will change. If the change is too intense (too black), undo and in the Options Bar, lower the Darken Amount. If the Red Eye tool doesn't completely address the problem, try the Color Replacement tool (found nested under the Brush tool in the Toolbox). Option-click (PC: Alt-click) to sample a color, and then paint with the tool to replace the color with your sampled color.
Q5:	How can I straighten a crooked image? I opened an image I took with my camera, but it's not quite straight. Is there a simple fix?
A5:	Use the Measure tool (found under the Eyedropper tool in the Toolbox) to drag a line along something in the photograph that is supposed to be straight (the horizon for example). Then from the Image menu choose Rotate Canvas>Arbitrary. The dialog will automatically have the angle that you just measured. Click OK and you're done! The same technique applies to scanned imagesuse the Measure tool to drag along the top or bottom edge of the crooked photo, then go to Image>Rotate Canvas>Arbitrary and click OK.
Q6:	When should I sharpen my images? I have been told various things about when I should sharpen a scanright away, at the end, etc. So what's the best answer?
A6:	There are various opinions about this, but in general, I would sharpen late in the processor even as the last thing you do. If you had an image with lots of small scratches and you sharpened it first, you'd get lots of nice sharp scratches. It would make more sense to deal with problems such as dust and scratches and then sharpen once those problems have been fixed.
Q7:	What is Unsharp Mask ( USM )? POLLY REINCHELD
A7:	Unsharp Mask is a sharpening filter (found under Filter>Sharpen) that allows you to enter settings to determine how an image is sharpened. (Most sharpening filters are automatic and often don't give the results you may want.) The settings you use depend upon the end result: Web or print. For print, use settings such as these: Amount: 100150%; Radius: 23; Threshold: 1012. Note: Sharpening will always look more obvious onscreen than it will when printed, so try not to be influenced by what you see on your monitor (I know, it's hard, but you gotta ).
Q8:	How do I get sharp, crisp photographs for the Web? Specifically, what is the secret to getting sharp, crisp photographs on my website?
A8:	When you lower the resolution to 72 ppi, sometimes the image does not appear as sharp. Try using Unsharp Mask (Filter>Sharpen) with settings such as: Amount 100%; Radius 1; Threshold 4. Let your eyes decide if it is sharp enough. Also, if you are saving as a JPEG, try not to use too much compression because that can also make the image look blurry.
Q9:	How can I avoid color " halos " when I sharpen? I find that when I use Unsharp Mask, I often notice small areas of color that weren't there before I started. The image looks sharper, but some colors have changed. How can I get around that?
A9:	One simple method is to change the color mode to Lab Color (Image>Mode) and apply the sharpening only to the Lightness channel in the Channels palette (Window>Channels). In fact, many people recommend using this method all the time. Not a bad idea.
Q10:	Why does Unsharp Mask sharpen? If it's called Unsharp Mask, why it is used for sharpening?
A10:	The term Unsharp Mask is based on a "traditional" film method of sharpening, in which a series of blurry negatives are placed over the original negative. It may be an odd name , but it's the best of all the sharpening filters.
Q11:	How do I get rid of digital noise and luminance noise?
A11:	Try the Reduce Noise filter (Filter>Noise), taking advantage of the preview option to see how you're doing: click-and-hold in the preview window to see the "before," let go to see the "after." If the Basic settings don't do the trick, click on the Advanced radio button to apply the filter on a Per Channel basis.