Photoshop 6 for Windows Bible- P32:If you are reading this foreword, it probably means that you’ve purchased a copy of Adobe Photoshop , and for that I and the rest of the Photoshop team at Adobe thank you. If you own a previous edition of the Photoshop Bible, you probably know what to expect. If not, then get ready for an interesting trip. | Chapter A Constructing Homemade Effects 11 Figure A-13 To blur more subtly increase the central matrix value and the Scale value by equal amounts. Edge-detection Many of you are probably beginning to get the idea by now but just in case you re the kind of person who believes that friends don t let friends do math I ll breeze through it one more time in the venue of edge-detection. If you really want to see those edges enter 1s and 2s into the neighboring options in the matrix and then enter a CMV just small enough it s a negative value after all to make the sum 1. Examples appear in Figure A-14 for your viewing pleasure. Figure A-14 To create severe edge-detection effects enter a negative CMV just small enough to compensate for the positive values in the matrix. 12 Extra Reading Photoshop 6 for Windows Bible To lighten the edges and bring out the blur raise the CMV and enter the resulting sum into the Scale option box. The first example in Figure A-15 pushes the boundaries between edge-detection and a straight blur. Figure A-15 To blur the edges increase the central matrix value and then enter the sum into the Scale value. Non-1 variations Every image shown in Figures A-7 through A-15 is the result of manipulating matrix values and using the Scale option to produce a sum total of 1. Earlier in this chapter I showed you what can happen if you go below 1 black images or above 1 white images . But I haven t shown you how you can use non-1 totals to produce interesting if somewhat washed-out effects. The key is to raise the Offset value thereby adding a specified brightness value to each pixel in the image. By doing this you can offset the lightening or darkening caused by the matrix values to create an image that has half a chance of printing. Lightening overly dark effects The first image in Figure A-16 uses nearly the exact same values used to create the extreme sharpening effect in the last image of Figure A-8. The only difference is that the CMV is 1 lower 8 down
