Any tutorials on using the alpha channel?

  • nestman

    nestman - 2011-03-10

    I am new to using layers and need some help to get started, but I can't find anything on youtube or other website that shows me how to use layers in Seashore.  There are tutorials for PhotoShop, but that doesn't help me much.  I am trying to design a business card where a portion of the background photo shows through the image in the top layer.

    Can someone point me in the right direction?


  • ChrisR

    ChrisR - 2011-03-10

    I don't know where you would find tutorials, except on the Seashore website (I'm sure I read through quite a long help section there).

    But briefly :

    1. Open an image in Seashore - that's your base or 'Background' layer
    2. Open another image, select the portion you want, and choose Edit > Copy
    3. In your first image choose Edit > Paste - that then becomes 'Layer 1' after you click the 'New Layer' button
    4. Next to each layer there is an i in a circle - click that and you can do various things including opacity, blending, etc

    • You can also create new blank layers in Layers > New Layer, into which you can paste images or selections.
    • You can also duplicate layers, create Text layers (the way Seashore handles text is VERY strange if you're used to Photoshop or other editors - the best way is to create a new layer and add text into it).
    • You can also do all the usual stuff like Rearrange layers, Merge layers, Rotate, etc.

    Try the Seashore Help from their website, or experiment using Seashore.

  • Stephen Siciliano

    If you want to edit the Alpha layer directly, you can do that in seashore too at the bottom of the window there is an icon that looks like an eye and two layers next to it. Click the one that looks like two layers and choose Edit Alpha Channel Only. This allows you to draw directly into the alpha channel if you have an advanced mask you want to do. If you don't see those icons because you turned the Status Bar off you can go to Image > Channel Editing > Edit Alpha Channel Only.

    Also, short of editing the alpha layer directly you can just use the selection tools to select the part of the image you want to show through and just deleting those sections.


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