Different Layers and their correct applications ? ? ?

Hi,
I promised myself I would get to grips with Layers this year. Can someone please explain in laymans terms the difference between an "adjustment layer" and a "layer mask"
Thanks
Ian
PS, I'm using elements 11

Basically an adjustment layer is a standard photoshop manipulation, like curves or hue/saturation, but you can edit it any time after the fact. So if you just hit CTRL+M for curves, and apply, you can't change it anymore, with adjustment layers, you always have the adjustment available to change.

Another advantage of adjustment layers, is that they automatically apply themselves to every layer beneath them in the layer stack, while those on top aren't affected. If you want an adjustment layer to only affect the layer directly below it, without using masks, right-click on the adjustment layer and select "create clipping mask".

Layers themselves can be thought of as a stack of papers viewed from above, with the bottom most layer in the layers panel (typically labelled "background" by photoshop) being the lowest sheet in the stack, and vice-verse.

An adjustment layer, just like any layer in photoshop, can have a layer mask. A mask is, to put it as simply as possible, like a cutting out an image with scissors, with black representing the parts you have cut off. The advantage of using a mask verses simply erasing is that changes aren't permanent, just like applying an adjustment vs adjustment layer. You can always paint in with white the parts of the layer you want to keep, and black to erase. Any shades of gray in between are transparent.

To give an example, say you want to lighten someone's face on a photo. You could first apply a curves adjustment layer, and brighten the image, but it's also going to lighten the whole image.
So now you select the white box next to the adjustment in the layers panel and press CTRL+I to invert the mask, making the photo look as though there is no adjustment. In reality it's just that the effect of the adjustment isn't affecting any part of the image.
Finally, select the brush tool, with a large size and softness, and paint white on the mask layer where in the image you want the curves to have effect (the face in this case), and if you make a mistake, just paint black on the curves layer to remove the effect.

Another example of using masks is with the gradient tool, if you want an adjustment layer (or any other kind of layer really) to gradually blend with the one below it, create a layer mask, and drag a black-to-white gradient across the layer mask. This might be useful if one half of a photo is darker than another, and you use an adjustment layer with a mask to gradually lighten or darken the image across to balance it out.

I'm really not sure why people find masks confusing, it's just a black and white image that controls how transparent the layer is in any given place.

Thanks for your detailed post. Very informative and has answered my question.
Ian

A mask is not actually an adjustment or edit of any kind - it simply lets you dictate which parts of the image you want your adjustments or edits to show through on.

Look straight ahead at something interesting. Now cover one of your eyes with your hand - that's a layer mask. Throw on a pair of red-tinted sunglasses - that's your adjustment layer; you can take them on and off as you please, and slide them up and down the position of your nose.

Now.... put the red sunglasses on and cover one eye with your hand - now you've got an adjustment layer partially showing through a layer mask.

Duplicate Post ( sorry )

Me thank you to for the explanation.

Thanks RandMan ( I replied to you the other day but deleted the wrong post :0 )

That's a very helpful link Kim, cheers for that. Took a look at your Flicker, some very nice images on there !!

tons of online resources and tutorials, if you prefer a book, I like a book called - surprise! - Layers by Kloskowski. Any photoshop book will have info too, but this one is only about Layers, nothing else. And it's not 7lb and 40 inches thick