Right now we are in the mask channel, we are through with the mask channel. What we want to do is use the mask channel to silhouette this dandelion from the background. First move, click on the name RGB so you are back talking to the image itself not to that mask. If we are going to get rid of the pixels that constitute the background of this well we could erase them but I am a big fan of doing things non destructively. Anytime you can do it non destructively that means that if you mess up, you can come back tomorrow and reclaim pixels that you thought you had wiped out. So we need to do something in the Layers palette to make this possible.

Click on the tab for the Layers palette and you will notice that you just have one layer, it's named Background and the word Background is italicized. Photoshop is telling something here. it's telling you that this is a base layer, it's like something glued down to a piece of foam core, we can't slide anything under it and we can't induce transparency in this layer.

So we need to un-glue it, very easy to do. Just double click the name Background and it proposes to name this layer 0 which is just fine, you can just click OK. In doing that, we have now made a floating layer, that means that we can have transparency in this layer and that we can have something underneath it. Let's wake up that mask that we created. Go up to Select>Load Selection and you may see a channel named Layer 0 transparency, just ignore that, click the pop down and choose your Red copy, remember that's your mask channel. Click OK and you now have crawling ants on your dandelion.

At the bottom of your Layers palette, look for the little gray rectangle that has a white hole in it, hover over and the tool tip tells you what it does, Add layer mask. When you click that, your active selection now becomes a layer mask. You can tell by the festive ging in background, that's Photoshop way of telling you, you have transparency. But now you have silhouetted the dandelion and what's so cool about this is that you haven't thrown away any background pixels. All the pixels in the image are still there we're just seeing the ones that show through the opening in our dandelion mask and take a look at your Layers palette. You see something important there. You now have two icons in that layer and it tells you that you have the pictorial pixels and you have the mask governing the visibility of those pixels. If you click on the thumbnail for the mask, the little black and white thumbnail, and hold down your Alt key on Windows, your Option key on the Mac, then you can look at just the mask.

Option or Alt+click on that thumbnail again and it's back to the image mask. If you hold down Shift and click on that mask thumbnail, you disable it, it's still there but it's not doing anything. You re-Shift+Click on it and now it's back to being an operating mask. Again because we are headed toward InDesign with this document, we don't have to save it as a TIFF, we don't have to save it as an EPS and if we did, we would loose their transparency.

So we are just going to save it as a PSD. Let's save it under a new name just to be safe. Go up to File and choose Save As and I am just going to save my on my Desktop and I will call this dandelion_silo sort of the industry bad shorthand for silhouette. Let's save a little bit of file size, here where it says Save Options, we don't need to save our Alpha channel, it's now being used as the mask and we don't need the Alpha channel itself so it's redundant and save a teeny tiny bit of file size and because we have asked it not to save the Alpha channel Photoshop is all I am going to save it as a copy which we are doing anyway; click Save. You may see this Maximize Compatibility dialog, the right answer is to click OK and now we are finished with this, and we can place it into an InDesign page if we like and you will see that everything shows through a round the dandelion. You will see things show realistically through the interior of the dandelion and in effect, you are sort of doing photo compositing in your page layout because InDesign understands transparency in PSDs.

We are through with this file, so we can close it. File>Close. Because we saved under a different name, Photoshop thinks we still want to save our old image, we don't, we like our dandelion_silo that we saved on the Desktop. So just click No.