When looking to create or enhance textures the Emboss Filter is a handy tool. It allows the illustrator to create embossed, beaded and engraved effects over large areas consistently and quickly. Embossing works by identifying areas of high contrast and adding two areas of pixels (white and black) on opposite sides of the high contrast area. The white and the dark represent the highlight and the shadow of the embossed area and are what create the effect.
To understand the concepts involved lets just make a black dot on a blank layer and hit emboss (Filter>Stylize>Emboss). We can see that the layer has been rendered to a middle gray with a highlight and a shadow cast on opposing sides of the original dot. By setting this layer to Overlay we will get rid of the middle gray and allow the highlight and the shadow to pass down to the layers beneath. In Photoshop parlance, the Overlay feature Screens the white pixels, Multiplies the dark pixels and makes all the gray pixels transparent.
Experimenting with this filter is the best way to get a handle on it. Try embossing objects with crisp and blurred edges. Keep in mind that embossed layers on Overlay mode are best used on top of a layer(s) which are neither too light nor too dark.
OK, assuming that we can now paint, blur and emboss an individual group of pixels as described above, is it safe to assume that we can paint, blur and emboss a screen full of them all at once? Youbetcha!
Well, by making a selection of each space simultaneously, modifying that selection (contracting, inverting, feathering as needed) then using that selection to fill an entire layer with a gazillion little fuzzy black dots- we are able to prepare an entire image to be embossed in one fell swoop. Cool Huh? Heres how it is done
Color Range is a Photoshop menu item which creates selections based on the similarity of a group of pixels (so you could build a selection which included just those pixels which were between 5 and 18 percent black for instance). We are going to use it to identify our sketch lines and tease them from the white of the paper and thus create a selection of every thing at once. Pretty cool huh?
Making Color Range perform correctly is the tricky part and you might have to deselect and start over several times before you get exactly what you want. (TIP: if you dont get the right selection try sampling a wider or narrower range of pixels). We will then expand this selection (Select>Modify>Expand) until it reaches about half of the distance to the center of the dot (or where you expect to put the dot).
Trouble shooting the Emboss filter:
Do you have a selection active while trying to emboss?
Deselect and try again.
Is the embossed layer set to Overlay?
On the Layers palette look for a drop down menu and set it to Overlay.
Is the embossed layer on top of a relatively dark background?
It should be.
Do you have an Innie or an Outie?
If the pixels on the layer are supposed to look like they are raised from the canvas, the highlight should be on the upper left and the shadow on the lower left and Vice Versa. You can set this in the Emboss dialog box- look for the circular
Has the embossing made your original image flatter than it was at the start?
Try using a soft edge brush and erasing the embossed pixels around all the edges. Have the effect strongest in the center of interest and make it fade gradually towards the edges.
If you are having trouble using Color Range it might be your sketch.
Color Range works best with a clean linear sketch on bright white paper. A clean graphite sketch on Marker paper works well and a smeared one on tracing paper often does not.
Embossing can yield garish results and is usually best when its effect is subtle so be cautious with the dialog box. Avoid setting both of the parameters to their maximum. If you wish to strengthen the effect emboss something lightly then duplicate the embossed layer and then blur, mask or blend to make it behave.
Is the effect still too strong? Does it Cover too much of an underlying layer?
Try this Double click on the layer icon and use the Blend if slider bars (hold the Option Key to split them and focus the effect) by tinkering with this you should be able to drop out certain pixels.
Andrew Swift, CMI, FAMI is the sole proprietor of Swift Illustration and Chief Creative Director with iso-FORM. Andrew earned his MS in medical illustration from the Medical College of Georgia in 1999. Following graduation, Andrew worked as an assistant professor at MCG with a joint appointment in the Department of Medical Illustration and the Department of Surgery, Section of Neurosurgery. Andrew was an associate professor with the Medical Illustration Graduate Program from 2000 until 2010. Andrew has been a Professional Member of the Association of Medical Illustrators since 2000, and was recognized as a Certified Medical Illustrator in 2002. Andrew's illustration work has won numerous awards including the Ralph Sweet Member's Choice Award that he has won 3 times.