Skill Level Intermediate
- [Sean] Hey, everybody, Sean Duggan here and this week on Mobile Photography Weekly, we're going to take a look at some interesting uses for the depth maps that are created with photos shot using the Portrait mode on dual camera iPhones. In Portrait mode, both lenses are used to distinguish between the foreground and background and create a depth map that is then used by the iPhone to apply live software-generated blurring to the background areas. In iOS 11, Apple made this feature available to other developers and in this episode, and subsequent installments, we're going to take a look at apps that let you do some pretty cool things with those depth maps.
So, the first app that we're going to check out is called Focos, or Focos depending on how you want to pronounce it. It's spelled F-O-C-O-S and it's made by the same developer as MaxCurve, which is a really useful curves-based processing app for iOS that I've covered in a previous episode. When you open up the Focos app for the first time, it'll be in Camera Capture mode and it'll be showing you the view from the 58 millimeter lens that you would see in regular Portrait mode in iOS. And just like in iOS, you would tap on the area that you want to have in focus.
Unlike the Portrait mode in iOS, however, you can tap on the background and have that be in focus while the foreground is out of focus. So, that's not a feature that's available in Portrait mode in iOS. In Portrait mode, you pretty much can only have the background be out of focus, not the foreground. Just tap back on that front camera to make that the focus point. Now, there are two different ways to use the camera. The first is called Edit mode, which is what you see here. You see that little picture icon in the gray area to the left of the shutter button, that means that if I took a picture, it's going to immediately take me into editing mode.
That's not terribly useful, especially if you want to be taking several pictures. So, if you want to take pictures without having to go immediately into Edit mode, just tap on that picture and it'll put it into Continuous Shooting mode, which just means that you can take a picture without having to go and immediately edit it. Most of the time, I just use the native iOS Camera when I want to access the Portrait mode and its accompanying depth map capabilities. But just remember that you do have to be shooting in the Portrait mode in order for the depth map information to be generated. Alright, over here in the Focos app, I'm going to tap on the film strip in the bottom and I'm going to go and open up another image to work with.
So, the first thing I get to do is decide what is in focus, and just as I mentioned when using the camera part of the app, I can tap on the areas that I want to have in focus, and like we saw in the Camera app, I could also tap on the background to have that be the area in focus and have the foreground out of focus. I really appreciate that level of creative flexibility in terms of determining what part of my image is in focus and what part is not. I'm going to tap back on the man's face and now I can use the slider here to adjust the level of blur in the background, so we'll put, actually, quite a bit of blur on there.
That looks pretty good. Next I can go and adjust the shape of the aperture. So, I have several different classic aperture shapes here and down at the other end, I've got some fun shapes like stars, hearts, clovers, et cetera. I'm just going to go and choose the very first aperture shape. This might be hard to see, but pay attention to what's happening with the shape of those highlight blurs in the background. You can see how they are changing depending on the aperture that I choose.
Next I'll tap on Highlights and I can adjust the brightness of those highlight areas. In the Vivid controls, I can adjust the saturation of the highlight areas and with Rotation, I can actually rotate those little aperture shapes that are appearing in the Highlights. I'm going to tap on the lens button down at the bottom which'll take me to my Lens presets. So, there's a range of different Lens presets you can choose here. A lot of them are fairly subtle in terms of the differences in the blurred areas, but some of them are different in terms of how they affect the blurred highlights.
Plus, you can also tap on Custom and configure your own settings for how you like the image to be blurred. Let's go in here and choose Swirly, and you get these little previews of how the aperture highlights might be affected. We'll just leave it set to something like that. If you get something you like, tap on the heart and you can save a new Lens preset. And I'm going to use a two-finger gesture here just to arrange this image like that, that way, I can get a preview and have this be the thumbnail of this new Lens preset.
I'm just going to cancel out of there and not save that for now. Next I'm going to go to the effect settings, and that's the little magic wand down below there, that little star wand, and this is where it gets really interesting because here I can move this little slider, this yellow slider with a degree indicator on it, and I can see a three-dimensional representation of the depth structure in the image. So, that looks pretty cool, but notice what's happening down below. I can have access to the front bokeh and back bokeh.
So, bokeh is just another word for the blurry areas in an image. So, for instance, let me actually exit out of here and tap back on the Aperture symbol. If you notice in the middle ground there, there is a green lamp. If I come back here to the back bokeh, I can adjust this so that the lamp is not included in that blurry area. So, now if I come back to the Aperture symbol, you can see that the lamp is in focus now.
So, that's really cool that I have that degree of control over what is in focus and the range of the different bokeh areas. Let me adjust this again here so I get access to the back bokeh slider and let's bring this up here, just like that. And let me adjust this so I can have access to the front bokeh slider and we can adjust that as well. So, if I tap the plus, I have the ability to add depth filters, and these are filters or image adjustments that are based on the depth map in the image.
It's going to use that depth map as a mask through which to apply the adjustments. So, let's just check out Brightness here. Normally the adjustments are linked, but if I tap on the little yellow link button, it'll unlink them and now I can adjust the brightness of the background independently of the foreground. That actually works pretty good. I'm also going to brighten it up a little bit and that looks pretty good, maybe a little bit more brightness. Can't go too far, otherwise they start to lose contrast on the hat. I'm going to tap the check mark to apply that and notice that I now have a new entry for Brightness there.
I'll tap the plus symbol and let me go and get Contrast. Unlink the background from the foreground and then I'm going to turn up the contrast in the foreground, which just gives me a little bit more depth in the dark tones in the hat. Alright, that looks pretty good. And finally, one last adjustment, I'm going to do a Saturation adjustment. Unlink the background from the foreground. I'm going to desaturate the background and saturate the foreground. Alright, that looks good. Now, couple of other things here. One is that, if you want, you can adjust the depth map for each of those adjustments separately.
So, I can tap here and drag on the front part of the saturation adjustment and I can change the depth map that's being used to apply that adjustment to the image. And if you want to get rid of an adjustment, just press and hold on it and then drag it to the little trashcan that appears in the lower right. If you want to go and change an adjustment, just tap on it. So, I'll tap on Brightness and you can get back in there and adjust it as you see fit. Alright, let me open up another image to take a look at the very last feature.
So, the last feature is a Patch tool, indicated by the little paintbrush in the lower right. The Patch tool is used to patch any gaps or holes in the depth map that is generated by the camera. So, you can see here, in this image, I do have a little gap there in the dark area immediately underneath the round rope ball and the rock that's right next to it. Right now I'm set to the Depth setting here, so I can adjust this and it's going to adjust the areas that are rendered in focus, which are represented by the red areas.
So, that's looking pretty good right there. I think what I want to do is paint in the center part of that rope ball and then fill that gap a bit, so I'll choose the Brush, and you can have different colors for that. I'm just going to leave it set to red and I'm going to use a pretty big brush initially and then just brush over that there. I'm going to come in here and brush over this, taking care not to get too close to those edges which are already nicely defined by the depth map.
Now I want to show you one other thing and that is, if I make my brush small and I need to work here, I get a little nice inset up at the top, which makes it really easy to see what's going on. But let me actually make the brush a little bit bigger and zoom up using a two-finger gesture. Check out what's happening here when I brush along the edge of this rock. Even though my... Finger is slightly extending over the edge of the rock, it is recognizing that that is a contrast edge and it's not extending it, so that is really useful.
Alright, that looks pretty good for now, little bit of a touch up right there, and let's go tap on the Aperture and come back and play around with that. Alright, that looks pretty good. The ability to take photographs that come with a corresponding depth map is a really interesting development in photography and a great example of how computational photography is working its way into the photos that we can take with our mobile phones. It's also really cool that apps like Focos can access this image information so that we can modify the focus in the photo after the fact as well as use the depth map to apply additional processing.