Join Tim Grey for an in-depth discussion in this video Unlinking an image from a mask, part of Photoshop CS6 Selections and Layer Masking Workshop.
In most cases, when working on a composite image in Photoshop, the Layer Mask associated with a particular Image layer is created very specifically for that image layer, and as such, it's important to keep the two locked. You want to make sure that if you make a change to the image that affects the size of the image, for example, that the Layer Mask itself also changes in size. But sometimes, you actually might want a different behavior. Let me show you an example of a situation where you might want to unlock a Layer Mask from the layer. In this case, my project is to display this image in a square format set against a different backdrop.
So, I have an image. A relatively wide shot of some cape buffalo at a watering hole and I'd like to essentially inset the image of a single cape buffalo, shot close up on that background image. Let's start off by creating a Layer Mask for this particular image in a square shape. I'll choose the Rectangular Marque tool and then I'm going to set the style to Fixed Ratio, and make sure that my width and height are both set to equal values. So, in this case I'll just set them both to 1. And then, I can Click and Drag in the image in order to create a square selection.
In this case, I think I'll include most but not quite all of the image vertically. I'll leave a little bit of space there, and obviously in a square format with a horizontal image, I'm not going to be able to include the entirety of the width of the image. I'll go a head and leave that selection as it is. Let's assume for the moment that this is a selection I'm happy with. So, this is the exact area of the image that I actually want to show. So, with that selection active and making sure my close up shot is active on the Layers panel, I'll go ahead and click the Add Layer Mask button at the bottom of the Layers panel.
That will add a layer mask based on the selection. So now I have the cape buffalo image essentially cropped into a square set against the background of the larger group of cape buffaloes. Of course, the image is a little bit to large here. And so, I want to re size the image. Clearly, it's very, very important in this case that I re-size both the image and the Layer Mask. And so, with the two locked, you can see the Link icon in between the two. I'll go ahead and choose Edit and then Free Transform.
And then I'll hold the Shift key, and I will re-size the image. So I'll go ahead and re-size, dragging one of the corners while holding the Shift key, so that the Aspect Ratio is maintained. And then, I can move the layer around within the image before I commit to the re-sizing, just to make sure that I'm happy with the overall size. So, perhaps I want to make that a little bit smaller or perhaps I want to put it in a different position. Let's assume that we're going to put it down here in the bottom right corner, not right up against the edge of the image but reasonably close, and so, I then might want to continue to adjust the sizing.
Let's assume that this is a good size for the moment. So, I'll go ahead and click the Commit button on the Options bar. I could also double-click inside the Bounding box or press Enter or Return on the keyboard. That will apply the re-sizing, and again both the Layer Mask and the image were re-sized in sync with each other. But now, I've decided that the cropping wasn't quite right. I want to include a little more of the cape buffalo. I cut off a part of its horn here at the top of his head, and so I'd like to move that. Well, I can select the Move tool, but right now if I move this object, I'm going to move both the Layer Mask and the image.
I only want to move the image, not the Layer Mask. And so, I can unlink Layer Mask and Layer. I'll go ahead and click on the Link icon in between the two on the Layers panel, and then, in this case, I want to move the image, not the Layer Mask, but the image. So, I'll click on the thumbnail for the image itself on the Layers panel. And then if I Click and Drag in the image, I'm moving only the image and not the Layer Mask. So, you can see that I can adjust the position of the image within the window, essentially, that I've created for that image so I can fine tune exactly where I position it within the frame.
I do need to be careful that I don't drag it too far so that I'm showing the edge of the original photo. Not that it's necesarily a problem to see that edge, but it means that I'm no longer filling the shape the way I intended. So, I'll fine turn the positioning here. That looks to be pretty good. I highly recommend that you get in the practice once you've moved the image or moved only the Layer Mask, if that was your preference, that you relink the two. That you turn on that Link icon by locking the Layer Mask and the Image Layer together again. That will help insure that if you inadvertently move the Layer, you're moving the Layer with both Image and Layer Mask in sync. That's usually somewhat important, and as a general rule, I would say if you're moving an Image Layer that has a Layer Mask, you probably want to move both of them at the same time.
So, as a rule, I keep the Layer Mask and the Image Layer locked only unlocking when I need to move one or the other independently. So, as you can see, in certain situations, you may want to delink the Layer Mask from the Layer which gives you a little bit more flexibility for creating interesting layouts in Photoshop.
- Anti-aliasing and selections
- The case for not feathering selections
- Adding, subtracting, and intersecting
- Inverting a selection
- Mixing and matching selection tools
- Advanced selection techniques
- Creating composite images
- Applying targeted adjustments