Hold down the alt/opt key and drag the layer mask in the layer's pallet to the other layer.
It just disappeared when I tried that. To clarify I want to mask a different image but with the same mask shape and size. Same solution? Also how does it know where to place the mask? Or do you place the layer who's mask you're copying where you want it to be?
If it's in a different image, then you have to do it another way. You can just drag the whole layer with the layer mask to the other image, Then do the alt/opt drag to the layer you want to apply the mask to, then delete the layer you transferred. If the images are the exact same size, you can create a blank layer mask on the target layer you want to apply the layer mask to from the other image. Select that mask - NOT THE LAYER'S IMAGE. Then use apply image by setting the source in the drop down menu to the image from which you want to transfer the layer mask from. Set the layer to the layer from the source image with the layer mask. Set the channel to the source layer's layer mask. Set the blending mode to normal.
OK Chuck. I give up. I have looked and looked, but I can't find any horses in those pictures.
BTW You have actually helped me with this thread. I think I tend to over complicate copying layer masks, and always try using at least two modifier keys, so I tend to end up with an inverted mask on the target layer. Sometimes you have to stop, think about what you are doing, and engage your brain. It's the last bit that gets me every time
Can you copy a layer mask (size and shape) from one layer to another? Thanks
A layer mask is just a selection. In Photoshop hold down the Ctrl key on a PC or the CMD key on a mac and click on the layer mask in the layers palette that you want to copy. That will load the Layer Mask as a selection.
Next target the layer you want to copy the layer mask to. Then click on the add layer mask icon in the bottom of the layers palette to create the copy. You could also save have saved the Layer mask selection as a new alpha channel. Alpha channels, layer masks and selections are basically the same thing. Target a layer that has a layer mask and look in the Channels palette you will see a channel name "Layer Name Mask".
If you want to copy it to a different image in a different document. You can copy it if the document have the same pixel size canvases. From the channels palette you you can drah the "Layer Name Mask" or the saved Alpha channel from the source document and drop it on the other document to add it to the second document Channels palette. Once there you can load it as a selection and add it as a layer mask the the layer you want it on. If the two document have different canvas sizes You can still drag and drop the channel however the size and alignment of the mask will most likely not be what you want.
You can also duplicate layers from document to an other. layer has a layer mask the duplicate layer will also have one. Photoshop will Duplicate all the Pixels the duplicated layer may well has a size different from the receiving documents canvas size. Photoshop supports any size layer. Layers in a document may have different sizes.