Saving an interactive image to PNG

Our next file format PNG is very popular in the world of interactive design. Like TIFF, it allows you to save full color graphics with lossless compression. However unlike TIFF, it does not support layers. However it does support transparency. Now let's say I want to save this image complete with transparency to the PNG format. I'd go up to the File menu and choose the Save As command and then I'll switch my format from PSD to PNG, which is PNG. And notice that I've already created this file in advance just so I can lift its name, so I'll click on it to select it.

Also notice down here that Photoshop not only automatically deselects the Layers check box, but it also dims the check box so I can't turn it back on and As a Copy is checked. So what that means is Photoshop is breaking the link between the file that I'm saving and the file I have opened and there is no way I can change that. I'll go ahead and click on the Save button and because I do want to overwrite the file I'll click OK, and I get the PNG Options dialog box here. You have two Compression options either None, which is a very fast save, or Smallest which is slower.

However the Smallest option is the only one that applies the lossless compression, and you get much smaller files as a result, so definitely turn it on. You also want to set Interlacing to none, these days there's no reason to save Interlace PNG graphics, and then click OK in order to save off that file. Now it is taking a moment or two for me to save the image, but now it's done. Notice that my file is still called Art with transparency.psd, so this is not the PNG graphic. Also notice over here in the Layers panel that I have a single layer, it's called Artwork; I want you to note that.

Now let's open the PNG image we just created. So I'd go up to the File menu and choose the Open command, and then I'll locate that file I just created, Transparent artwork.png and click the Open button and I'll zoom in and it looks for all the world like exactly the same image. And if I check out the Layers panel I do have a layer. It's not a flat background image; it's an independent floating layer. It just doesn't happen to have a name; it's called Layer 0 instead of artwork. But otherwise it is a single layer image where Photoshop and other applications are concerned.

Now let's take a look at saving a big whopping huge image to the PNG format. I'm going to switch over to my 45 million pixel panorama and then I'll go over to the File menu and I'll choose the Save As command. And just so I can lift a file name here on the PC, I'm going to switch the format to TIFF for a moment and then click on Antique theatre. Now I'll switch back to the PNG format and this way I can create a file called Antique theatre.png, and notice that the Layers check box gets turned off and As a Copy gets turned on.

Now I'll click the Save button in order to create that file. I'm going to turn on Smallest/Slow, set Interlacing to None and click OK. And notice how it's taking a while to save this file. However, I can go and zoom in and even use tools inside the file while it's saving. This is background saving inside of Photoshop CS6, and it's amazing because you can do all kinds of work while it saves as we're seeing down here in the lower left corner of the screen is still in progress. So in other words, the fact that the lossless compression where the PNG file format is concerned does slow down the saving progress.

It doesn't slow you down one wit. You can even switch to a different document window if you want to, and do work inside that file. And that's the beauty, not only of the PNG format, but of background saving here inside Photoshop CS6.