Photoshop: Layers & Masks

DIGITAL SESSIONS WELSH SCHOOL OF ARCHITECTURE - CARDIFF UNIVERSITY

PHOTOSHOP: LAYERS & MASKS

WASSIM JABI AND SERGIO PINEDA

DIGITAL SESSIONS WELSH SCHOOL OF ARCHITECTURE – CARDIFF UNIVERSITY DR. WASSIM JABI AND MR. SERGIO PINEDA

PHOTOSHOP: LAYERS AND MASKS INTRODUCTION The goal of this tutorial is to show you the power of using layers and masks in Photoshop to compose images. Very much like layers of trace paper, Photoshop allows you to layer images on top of each other.

Since pixels in an image can be opaque, translucent, or transparent, layers can be composited. In addition, masks are special images that are used to define the amount of transparency of pixels in a certain layer.

In this two-part tutorial, you will combine two images to create a complex composite image that would be tedious to create using other methods. In the first part, you will use a colorful background image to color-in text as you see in the image below. The same effect can be applied to apply texture to surfaces in an architectural drawing.

In the second part, you will insert a detail drawing (an exploded axonometric in the corner of a larger aerial view without an inset frame or border as you see in the image below:

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PART I STEP 1: CREATING LAYERS x Make sure you have the file ‘colorful.jpg’ before starting the tutorial. x Open ‘colorful.jpg’ in Photoshop.

x Select the text tool (the letter T) from the toolbar on the left. x Select the font Arial, Black, 100 pts. x Place your cursor on the left side of the image in the middle, click, and type "ARCHITECTURE" (all in upper-case.

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x In order to more easily work with the text, we are going to rasterize it (convert it to pixels). Right-click on the layer name and choose Rasterize Type.

x Add a blank/white layer in-between the text and the background layers. Click on the small tab in the upper right corner above the layers and choose New Layer.. (CTRL-SHIFT-N).

x Merge the text and the white layers. Select both layers by clicking on one layer, then holding down the SHIFT key and clicking on the second layer. Right-click on the layer name and choose Merge Layers.

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STEP 1: ADDING MASKS We are now going to use the resulting image as a mask. The white pixels will be opaque and not show the background, while the black pixels of the text will be transparent. In order to use the image as a mask, we will first create a mask layer. x With the top layer selected, press the Add mask layer icon at the bottom of the layers window.

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x When a layer has a mask, Photoshop adds a mask channel to the normal Red, Green, and Blue channels.

What we want to do is copy the image you see above into the mask channel. x Make sure the main layer and not the mask is selected (Click on the left-side box (the one that has the word ARCHITECTURE in it). x Select all the pixels (CTRL-A) and Copy (CTRL-C). x Click on the Channels tab (to the right of the layers tab). x Make sure only the bottom-most channel (the mask channel) is selected and visible (click on the eye icon to hide it for all other channels then select the mask channel so that it is highlighted). x Paste the image into the mask channel (CTRL-V).

x Switch back to the layers tab and click on the eye icon next to the top layer.

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x Click the eye icon next to the background layer to show it. x The background layer should now show through the letters of the "ARCHITECTURE" word.

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PART II The goal of this tutorial is to combine a detail image on top of an overall background image. The objective is not to have a frame around the detail image, but to have it naturally blend-in above the background image.

In order to do so, the detail image is placed in the corner on a blank background. We will fade the image diagonally from the centre of the image towards the detail in the lower-left corner.

STEP 1: CREATING LAYERS x Make sure you have the files ‘aerialview.jpg’and 'explodedaxon.jpg" before starting the tutorial. x Open ‘aerialview.jpg’and 'explodedaxon.jpg' in Photoshop.

x Select all the pixels in 'explodedaxon.jpg' (CTRL-A), (CTRL-C) x Click the title bar of the 'aerialview.jpg' window to select that file. x Paste the exploded axon image (CTRL-V).

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x Close the original 'explodedaxon.jpg' file.

STEP 2: ADDING THE MASK x Make sure the top layer is selected. x Click on the add vector mask icon at the bottom of the layers window.

x Click on the mask icon rectangle (the one on the right-hand side) to activate it. x Choose the bucket tool and change it to the Gradient tool. x Make sure your colors at the bottom of the toolbar are Black and White.

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x Drag a line diagonally one the image. It may take a few tries to find the best start and end position of the gradient that creates a good result.

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Wassim Jabi, Ph.D. is a Senior Lecturer at the Welsh School of Architecture Sergio Pineda, AADip is an Architect and a Professional Tutor at the Welsh School of Architecture