Merging, cropping, and scaling a panorama

- [Instructor] All right, now as you may recall, Photo Merge generates a layer for each and every stitched image. And assuming you turned on that Blend Images Together check box, then it automatically generates a bunch of layer masks as well. The thing is, these layer masks don't really do you any good. And so to see what I'm talking about, I'll Alt or Option + Click on the eye in front of this layer that ends with 34.jpeg. And I'll go ahead and zoom in on it as well. And then I'll Shift + Click on this layer mask thumbnail to turn it off, and you can see we have an abrupt luminance transition between the masked portion of the layer and the unmasked area.

And so in other words, editing that layer mask is never going to do you any good, so there's really no sense in having all of these layers. And even though this is a relatively small panorama, it's huge in memory. I'll go ahead and drop down to this little status bar and click and hold on the right-pointing arrowhead, and switch to Document Sizes. And notice these two doc values. The first one tells us the size of the image when it's flat, which is 96 megs, the second one tells us how big it is in memory with layers, which is a whopping 819 megs, or nearly a gig.

Which is mostly wasted where this image is concerned. And so what I recommend you do is bring back all the layers by Alt or Option + Clicking on that eyeball, I'll Shift + Click the layer mask to turn it back on, and then I'll go up to the layers panel fly-out menu, and choose Flatten Image, or if you loaded D keys, you have that shortcut of mash your fist C, that is to say Control + Shift + Alt + C here on the PC, or Command + Shift + Option + C on the mac. And that will generate a flat image file. And you can see down here in the status bar that both doc values are now 96 megs.

So it's taking up way less room in memory. All right, so I've already done that in advance where the good panorama is concerned. So the next steps are to crop and scale the image, and we want to do so non-destructively, so I'm going to convert this image to a smart object by double-clicking on the background, here inside the layers panel, and I'll go ahead and call this guy rice field, and then press the Enter key, or the Return key on the mac. Then I'll right-click inside the image window with the rectangular marquis tool, and I'll choose Convert to Smart Object, or again if you loaded D keys, you have a shortcut of Control + Comma on the PC or Command + Comma on the mac.

All right, now the typical way to crop the image would be to use the crop tool, and of course, you can do that if you like. And in my case, I would just go ahead and drag the bottom edge up, and now I'll press Control + 0 or Command + 0 on the mac to zoom out, and I would Alt or Option + Drag one of these sides inward so that they're both moving inward like so. Then I might drag this guy downward a little bit, what have you. Now even though my Delete Cropped Pixels check box is turned on, because I'm working with a smart object, there's no conceivable way to crop those pixels, and so I can just press the Enter key, or the Return key on the mac, to apply that change.

And if I were to now press the M key to switch back to the rectangular marquis tool, and Control + Drag this image around, you can see that I haven't lost any of the cropped pixels. All right, I'm going to press Control + Z, or Command + Z on the mac, to undo that move. Now in my case, I have some specific numerical values that I want to use, and so I'm going to crop my image by going up to the Image menu, and choosing Canvas Size, which by the way, has a default shortcut, of Control + Alt + C or Command + Option + C on the mac. Years ago, I successfully lobbied for this shortcut.

My reasoning being that the C not only stands for the word canvas, but it also stands for the word crop, because it is an alternate way to crop your image. And so I'll go ahead and choose the command, and then with the relative check box turned off, I'll dial in a width value of 3200 pixels, and then I'll Tab down to the height value and change it to half that value, which is 1600. And now I'll set the anchor to this top square right there, so that we're cropping away the left, bottom, and right edges, and then I'll click Okay.

Now this alert message right here is not just misleading, it's altogether inaccurate. No clipping is possible with a smart object, and this command doesn't even clip layers, so you can just go ahead and click Proceed in order to apply that change. All right, now we need to scale the image inside of its new surroundings. And I'm going to do that by going up to the Edit menu and choosing Free Transform, or you can press Control + T here on the PC, or Command + T on the mac. I want the top of the image to remain where it is, so I'll select this center top point, in a tiny reference point matrix over here on the left side of the options bar, and then I'll click on the W and change it to 47%.

I'm going to leave the height set to 100%. So in other words, I'm going to squish the image. Which you can often get away with when you're working with a panorama, because after all, the image has already been distorted so much in the first place. Now I'll just go ahead and drag this guy around so that I can't see this pole over here on the far right side. I'll zoom in so you know what I'm talking about. It's right there. So I'll just go ahead and drag this guy over a little bit. And then I'll press the Enter key, or the Return key on the mac, to apply that change.

And we have now successfully merged our layers as well as cropped and scaled the panorama. The problem is, we still have a few problems. The image is pretty washed out at this point. And you may notice that we still have some distortion. That horizon line is lifting and then falling back down. Which is why we'll correct all of those problems in the very next movie.