Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member
Ben: We've already talked about cropping, but hand in hand with cropping goes the issue of sizing. Sizing is a very important consideration if you're going to print. If I crop a whole lot, I may not have enough pixels left to get a good print at my chosen print size. Conversely, if I want to enlarge my image, I will need to be concerned about how many pixels I have, whether I have enough to get a nice sharp print. So sizing is a pretty critical issue near the end of your workflow. Fortunately, Photoshop makes questions of sizing very simple, thanks to the Image Size dialog box.
If I go up here to the Image menu and choose Image Size, I get this thing. Now what's cool about the Image Size dialog box is it's this very interactive little calculator that can make sizing questions very easy to understand, as long as you pay attention to what's going on. You want to really pay attention to this thing here, this thing here, and this state of the Resample Image box. And I think you'll see why as we go along here. I'm going to uncheck Resample Image so that we start here. Image size is divided into two sections.
I have Pixel Dimensions. This is the total number of pixels in my image. I currently have 5166x3744, for a total image size of 110 Megabytes. My Document Size is how big this image will print. So right now it will be 21x15 inches and it has a resolution of 240 pixels/inch. Now unfortunately, the camera industry has kind of wrecked this word resolution, because vendors will say, well, this camera has a resolution of 18 mega pixels.
Well, 18 mega pixels is not a measure of resolution. In fact, a camera does not have a set resolution. Resolution is simply a measure of how many pixels there are over a given distance. So right now, if I print this image, so that there are 240 pixels for every linear inch, it will come out to be 21x15 inches. Now I can pack those pixels closer together. If I go up to say 300, I go from 21x15 down to 17x12.
In other words, increasing the resolution is going to lower the print size, and that should be fairly intuitive. If the pixels are packed closer together, they're not going to take up as much space, so the print size is going to go down. And I can see from this thing over here that these three fields are locked together. I cannot change one without changing the other. If I change Width--let's say that I know that I want to print this at 24 inches wide, Photoshop automatically calculates a Height of 17.3 to preserve the image's original aspect ratio.
But with 5100x3700 pixels, to go 24x17 is going to drop my resolution down to 215 pixels/inch. If I spread the image out to be that big, or if I spread the pixels out to cover this much space, the resolution is going to drop to 215. Now, notice that these three fields are editable, as we've been doing, and they are locked together. I can't change one without changing the other. But these fields are not. I cannot change the total number of pixels in the image. That's why these three are locked together. If I change resolution, print size changes because I can't alter the total number of pixels.
However, if I check the Resample Image box, now these fields are editable. And notice there is one of these gizmos over here. Right now, Width and Height are locked together. I can't change one without changing the other. That's good; it will keep my image from being distorted. If I wanted to, I could turn off Constrain Proportions and now this lock is gone and this lock is gone. This would allow me to stretch the image out wider or higher. You'll rarely do that with a photo. I am going to leave that right there. So now, everything is editable.
So I have an image that's 21x15. Let's say I wanted that to print at 300 pixels/inch. I am going to change that to 300, and now what's happened is my pixel count has gone up. It's now up to 6400x4600. In other words, Photoshop has conjured up new pixels to allow me to get a Width of 21x15. The way, or the mechanism, the algorithm that it uses for generating those pixels can be controlled down here. And if you see, there's one that says that it is best for enlargement, so that would be the interpolation method that I would want to use.
So what's the best resolution to have? That really depends on your printer. Most inkjet printers will work best at a resolution of 240 or 300 or sometimes 360. This is a critical piece of information, and I think that's why you'll find that no printer manual in existence will tell you the printer's native resolution. In general, you can assume that an Epson Photo Inkjet printer wants images that are around 300 pixels/inch. HP printers typically want 240.
If you don't plug those numbers in, it's not the end of the world; it may not make any difference in final image quality. But working towards your printer's native resolution is not a bad idea. So let's say I wanted to print this at an 8x10 at 300 pixels/inch. Set my resolution to 300. I'm going to set my Width to be 10, and it gives me a Height of 7. Now you may think well, I want this to be 8x10, so I am going to put that on 8, but no, now this is at 11. Well, it turns out the aspect ratio of this image will not work. It does not equate to 8x10. So I am going to put that at 10 and just accept that I have to have a height of 7.
So, at 300 pixels/inch, you can see that my image has gotten much smaller. It's thrown out a lot of pixels and gotten me down to 3000x2100. If I want to go bigger, as I mentioned, I need to change my interpolation method. If I do go bigger, I'm going to risk an image that's very, very soft. That's why I was saying before, you've go to be careful with cropping. You don't want to crop down so far that you don't have enough pixels to print your image without doing interpolation. So it's best to try to keep from going beyond your original pixel count.
But if you have to, it's not the end of the world. Bear in mind that images that are printed very large are usually viewed from farther away, so razor sharpness is not so important. What if, though, I really, really wanted this to be 8x10. I've bought a pre-built 8x10 picture frame and I really want this to go in there. Well, there's nothing I can do from the Image Size dialog box. At that point, I would hit OK and I would go out here to my Crop tool and plug in, up here, a Width of 10 inches by 8 inches at a resolution of 300 pixels/inch.
Now my Crop tool will only drag out an 8x10-aspect-ratio crop. So you can see now I've got to do some thinking about where I want my crop to be, and now we're back to just what I was doing when I was shooting. I am going to work with this scene here in this window and try to find the best composition. I think that I want this tree here. I'm not sure that I need this part of the bridge over here. On the other hand, what I like about this part of the bridge is I am kind of getting this convergence of stuff here.
So take a look at this. I am going to turn off this Rule of Thirds grid there so that we can better see the image. So I've got that, or I've got that. That's a tough call. It's kind of bright over here, and my eyes are really wandering this way, which may not be such a bad thing, but I think because of that brightness, I think this feels more balanced to me, because the darkness here and the darkness here balance each other better than when I am over here and I introduce this white part of the sidewalk and all this other stuff.
So I think I am just going to suffer the chopped-in-half tree and take that. So that will give me an 8x10 that will fit in my pre-built frame. So, Cropping and Image Size, they work hand in hand. You may have to move back and forth. But again, the key to understanding the Image Size dialog box is to understand that when Resample Image is checked, the number of pixels in your image can change. When it's unchecked, they cannot and so these three items become linked together.
Get unlimited access to all courses for just $25/month.Become a member
180 Video lessons · 75798 Viewers
64 Video lessons · 94414 Viewers
86 Video lessons · 61930 Viewers
103 Video lessons · 31243 Viewers
Access exercise files from a button right under the course name.
Search within course videos and transcripts, and jump right to the results.
Remove icons showing you already watched videos if you want to start over.
Make the video wide, narrow, full-screen, or pop the player out of the page into its own window.
Click on text in the transcript to jump to that spot in the video. As the video plays, the relevant spot in the transcript will be highlighted.