Photoshop Background layer

Question

The background layer is locked by default. When I unlock it, PS creates a new layer layer0 and deletes the background layer.

Is this a bad thing to do. Does the background layer have any special significance or properties that it shouldn't be deleted/replaced? Should I instead copy of the contents of the background to another layer and leave the background layer alone?

I noticed that when I open an image, PS automatically puts the image on the background layer. How do you handle opened images before working on them.

Answer 1

It's not a bad thing to do. It won't do you any harm.

Keep in mind you can only do layer effects on a "layer," so the flattened default background isn't too useful.

If your image is a photograph and you want to do some manipulations, it's best to make a duplicate of the background first.

Answer 2

Photoshop is not "deleting" the background layer. It's unlocking it and renaming it.

When you open an existing image which is flattened, "Background" is just the arbitrary name which Photoshop calls the layer. If you create a new document, it opens with "Layer 1," which can be white, transparent, or a color, depending on your settings.

"Background" has no more special significance or properties than "untitled folder" or "Document1.doc."

Answer 3

The background layer is locked because it is the background and, by definition, can't be moved or resized without changing the dimensions of the document itself. In a single-layer image, like a jpeg, that's all there is. If you think about it, it's clear that you can't move the background around or resize it, because that is the image. So it isn't that Photoshop "puts the image on the background layer." The background layer is the image.

A non-background layer has special properties that a background can't have. The Photoshop engineers call it "big data" because it can be far larger than the visible image area. A layer can be moved, scaled, and otherwise manipulated without changing the dimensions of the image as a whole.

If you run a filter like Lens Correction or Liquify on a background, it will be promoted to Layer status automatically so that the filter can run. When you promote the background to a layer yourself, you also open up all the possibilities, as Jin pointed out, of layer effects and other manipulations that can't be applied to a background.