The OKI PRO 8432WT and 711WT laser toner printers produce soft, vivid full-color T-shirt transfers on light, dark, and colored garments. The white toner in the printers acts as the under-base or primer to support the CMY process color just as white ink does in a direct-to-garment printer. But how does the printer know where to place the white toner? The designation of the base layer is done through software in the design process. The preferred method for creating and controlling the white underbase requires the use of Adobe Photoshop's path tools. The path tools are linked to a little-known resource that can spark your creativity and save you lots of time by allowing to build your graphics from the bottom up. Here's how to take advantage of Photoshop path tools to create more intricate yet more efficient OKI WT laser transfers.

Photoshop Path Tools

If you haven't used Illustrator, FlexiSign, or LXi graphic design software, you may be wondering what a path tool is. Vector paths are simple shapes composed of points or nodes and the lines that connect them. All vinyl graphics made with cutting plotters rely on vector art. The plotter blades follows the path defined in the software. Click here for a more in-depth explanation of the difference between vector and raster artwork. As the name implies, Photoshop is used primarily as a raster photo editing application and is not suitable for creating vinyl graphics. But it's also used in lots of graphic design applications beyond airbrushing blemishes off of fashion models, so there are path and shape tools tucked away in the toolboxes. Because they define shapes with clean crisp edges, they're handy for precise extraction of foreground images from their background elements. Extracting raster elements with the path tool often requires using the tools to create a clipping path that can then be used to delete background pixels.
Fig 3. A clipping path and clear edges are required for white toner transfers on dark shirts
Fig 1: Here is the clipping path for our OKI WT sample. Like layers, you can name the path when you save it.

Clipping paths are also essential in the design of T-shirt transfers because they tell the OKI WT printer where to put the white toner (Fig 1). For step-by-step instructions on how that works, please click here to view or download the tutorial. The tutorial describes how to start with a full color raster image and select the CMY values you want to print, then convert those extracted pixels into a clipping path. It works, but there is a downside. You are essentially vectorizing a raster image. This is a process well known to vinyl sign makers because. As the aforementioned raster and vector article explains, vectorizing a raster image may require you to fine tune the resulting vector image to eliminate excess points and smooth out the paths. The same is true when you convert a raster layer to a path in Photoshop. The resulting clipping path may not be as precise as you want. The more precise your clipping path is, the better the registration will be between the CMY layer and the white underbase. So you may need to use the Direct Selection Tool to move, add, or subtract points to fine tune the path before it's usable as a white layer. The problem with this process is the fact that you're building your design from the top down. That can be an inefficient and cumbersome work flow.

Path Tools for Better Design

In addition to defining your white layer, the path tools in Photoshop can add distinctive elements to your design that make the most of the self-weeding characteristics of the laser transfer process. One of the advantages of laser transfer vs print and cut is the ability to create opaque images on dark garments without having to weed printed and cut heat transfer film. If you have to spend an hour optimizing your clipping path to create the white underbase for an intricate design, you're just trading time spent weeding for time spent designing.
Fig 3: Photoshop has an extensive symbols library.
Fig 2: Photoshop has an extensive symbols library.

But there's another potential benefit to Photoshop's path tools. In the toolbox containing the Pen, Text, Path Selection and Direct Selection tools, there are shapes and symbols as well. The most commonly used are rectangles, rounded rectangles, and ellipses. But at the bottom of the toolbox, there's a Custom Shape tool that opens what is essentially a vector clip art library (Fig 2). Like the brushes toolbox, this can be appended with several different sets of symbols, including Fleur-de-lis, arrows, paint splashes, and grunge effects. Very cool stuff. You can build your T-shirt transfer from the bottom up by selecting some of these symbols, dropping them into your design and then duplicating and rasterizing them to create the CMY layer. When you add the symbol, it will be visible in the layers panel. Duplicate the layer (Ctrl-J or Alt-J). Then rasterize the layer and add whatever colors, textures, or effects you want in the final design. The original symbol is still there in vector format to serve as the white underbase. Or just add the symbol and leave it as a white shape to add opaque white elements that enhance the overall design (See Fig 3 below).

Fig 4: The original shapes and symbols have been merged into a single shape, designated white underbase.
Fig 3: The original shapes and symbols have been duplicated as raster layers and colored. Then they were merged into a single shape, designated underbase. Ready to print.

Adding multiple symbols creates separate layers. These all need to be on one layer to serve as a single clipping path for an effective white underbase. This can be done by using the Path Selection tool. Paths can be copied and pasted in the Paths toolbox. Or you can just select the shape layers in the layers toolbox and merge them into one shape. The convert the shape to a clipping path and you have your white layer ready for printing. Tip. Once your design is done, you may find you need to resize, rotate, or move the CMY layer. If you do this without linking it to the clipping path, you'll ruin the registration of the CMY and white layers and cause some interesting printing problems. Since the white layer has been saved as a clipping path, it will actually clip the top layer and cut off any CMY elements outside the path. Those areas won't print. If you've forgotten that the path is out of alignment, this can cause quite a bit of head-scratching.

Fig 5: Connect your clipping path and CMY layers using the Add Layer Mask function.
Fig 4: Connect your vector clipping path and your raster layers using the Add Layer Mask function.

To prevent this, link them using the Add Layer Mask function. Use the Path Selection Tool to select the clipping path. Then open Layers, select your CMY layer and click on the Add Layer Mask button at the bottom of the layers tool box. Click it again to link the CMY layer to the clipping path. Now, if you move or resize the CMY layer, the clipping path and white base layer will move with it (FIG 4). This combination of raster and vector elements takes advantage of the extensive design capabilities in Adobe Photoshop. Photoshop isn't just for fashion photographers. It can also be used to create professional T-shirt transfers on dark garments with your OKI white toner laser printer.

The result is a transfer with brilliant color and intricate detail without spending hours optimizing paths created from raster elements. It's a simple matter of design efficiency. Since you have to have an optimized white underbase, why not expand your design vocabulary and save time by building it from the bottom up?