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Man Kei 發問於 電腦及互聯網軟體 · 1 十年前

Photoshop 的 Vector Mask 有什麽用途????


1 個解答

  • Ruby
    Lv 6
    1 十年前

    Gradient fill applied with Quick Mask mode active above. Identical selection shown in Standard Edit mode below.

    PhotoShop offers a wonderful little one click-wonder called the Quick Mask. It works in much the same way as the masks we have been looking at in this tutorial, but it is not applied to a layer. In fact, it is a temporary mask that can make selecting areas much easier. As with any mask, you can also use all painting tools for effects that would be impossible using only selection tools.

    And you will toggle back and forth. Unlike the layer mask which becomes and integral part of the layer, Quick Mask is a temporary setting. You cannot apply any effect to the document when you are in Quick Mask mode. This setting is simply a selection tool. However, it is a powerful selection tool, since any tool that will work on a grayscale image can be used to edit while in Quick Mask mode. Note how the foreground and background color change automatically to black and white when you change to Quick Mask mode.

    Although the mask is shown in red to represent rubylith masking (a holdover from the pre-digital print industry), black and white have the same effect as they do for layer masks. Painting a Quick Mask with the foreground as black provides a total mask, while white masks nothing.

    In this set of samples, I have started with Quick Mask mode activated. I chose the gradient tool and set a gradient fill from black to transparent, bottom to top. This will protect the area of the skaters from any effect.

    The second sample here is exactly the same, but I have returned to Standard Edit mode. The selection area is actually feathered, but of course there is no way to show that with the marching ants selection borders – probably the strongest reason to use Quick Mask often. In the Quick Mask version of this operation, it is very clear what areas are protected and which are not, as well as the level of transparency at all points in the selection. The final image (right) shows the result of filling the selected area with a 100% white fill.

    Rough selection done quickly with standard selection tools.

    Switching to Quick Mask mode makes accurate selection very fast, since you can use any paint tool. Quick Mask mode above and Standard Edit mode of the same selection

    Where Quick Mask truly shines is as a selection assistant. It is not difficult with most images to create a rough selection, but fine tuning it becomes a challenge when working with standard selection tools.

    In the samples at the left, I started first with a quick selection using the Magnetic Lasso tool. It is pretty rough and adding and subtracting from this selection would be an exercise in patience and endurance. However, if you switch to Quick Mask mode, you are able to use paint tools to get very accurate selections.

    To use paint tools, simply switch to Quick Mask edit. Choosing black as a foreground color with any tool will add to the mask. White as the foreground color removes the mask. I find that I am constantly toggling between Standard and Quick Mask mode when cleaning up a selection.

    Here is the final Quick Mask view before I changed to Standard edit mode and deleted the background. Hint: After deleting the background, feather the selection using a very low number or contract or expand the selection by 1 or 2 pixels and apply a blur to soften the edges.

    Learn to use Quick Mask. Remember the shortcut – the "q" key. Once you have completed one difficult selection with Quick Mask, you will be converted forever.

    Make sure you stop by again for part two of this tutorial when we will look at saving selections, alpha channels and importing images as masks.