Photoshop
Channels and Masks
Review Questions
- Name the two colour modes that have a composite colour channel.
- Name three colour modes that have a single colour channel.
- What is the bit depth of an alpha channel and what colours does it support?
- When an alpha channel is loaded as a selection, what do the white areas of the channel become in the selection?
- Do alpha channels add to the file size of the Photoshop file?
- Are individual RGB colour channels displayed in the Channels panel as greyscale thumbnails or colour thumbnails?
- When the composite colour channel is selected in the Channels panel and an alpha channel's visibility is enabled, what will be displayed in the image window?
- Describe two ways that an alpha channel can be created.
- What are the two methods for saving a selection as an alpha channel?
- To load an alpha channel from another document, what conditions must be met?
- What's the quickest way to load an alpha channel as a selection if you don't want to set any options?
- After viewing or editing an alpha channel, how do you restore the colour image in the document window?
- When editing an alpha channel using the painting tools, how will painting black over white areas affect a selection loaded from the channel?
- What advantage is there of editing a quick mask over editing an alpha channel directly?
- To remove an area from a quick mask, what colour would you paint with? How will this modify the resulting selection once you exit from Quick Mask mode?
- What is the keyboard shortcut for toggling between Standard mode and Quick Mask mode?
- How do you switch between editing a mask and the image containing the mask?
- When a name appears in italics in the Channels panel, what does that indicate?
- To permanently delete the pixels that have been removed via a mask would you apply or discard the mask?
- What advantage does a mask have over using the Eraser tool in removing pixels from a layer?
Bonus Questions
- If the Load Selection command is dimmed in the Selection menu, what does that indicate?
- How could you check to make sure that the black areas of an alpha channel contain no grey pixels that might affect a resulting selection?
- How can you change the stacking order of the R, G and B colour component channels in the Channels panel and why would you want to?
- What is commonly referred to as the "marching ants"?
- When viewing an individual colour component channel, it appears as a greyscale image by default. Do light areas in the channel represent more of the colour or less of the colour than darker areas?
Review Answers
To help you determine if you are on the right track, the answers to the Review and Bonus questions have been provided. Do all the work on the questions page before you take a look at the answers.
Photoshop - TOC - Introduction - Books -
Channels and Masks - Links - [ Questions ] -
Answers -
