Tutorial: Replace the Background of a Photo on iPhone

This photo of the Eiffel Tower is special. It was the first photo that I shot and completely edited with only an iPhone. After I returned from my trip to Las Vegas back in 2012 and from a trip to Paris shortly after, I looked for iPhone photo apps that would allow me to do more than just basic adjustments. The first app I found was Superimpose that I used to create this composition.

iPhone Photo Apps used for this shot

The photo is a composition. I shot it with my iPhone using ProHDR [iTunes App Store Link]. Then I replaced the boring blue sky with those dramatic clouds, converted it to black and white and added the searchlight.

I used three apps to post process this shot:

• Superimpose to replace the background with some clouds [iTunes App Store Link].
• Snapseed for the black and white conversion and dramatic look [iTunes App Store Link].
• Lenslight to add the search light at the top of the tower [iTunes App Store Link]

Step 1: Change the background in Superimpose App

 The first step is to replace the boring and dull blue sky with a more dramatic sky with clouds. Fortunately, there's an app for that. It's called Superimpose[iTunes App Store Link].

With Superimpose, I load two photos; first a background photo followed by a foreground photo. Make sure you load the two photos in the order I mentioned.

Then select the the areas from the foreground photo that you want to remove with either the magic wand tool or the eraser tool. The magic wand tool works like magic (pun intended) if the background you want to remove has a single color or shaded of a single color like a blue sky.

Once you've selected the areas you want to remove from the foreground photo, the background photo will be visible and, voila, you've got a new sky. For best results I recommend that you use two photos with the same orientation; landscape, portrait or square.

Load two photos in Superimpose to replace the background: A background and a foreground photo

In Superimpose, always load the background photo first; it's the photo that you want to have as a background; use a photo with a e.g. cloudy sky.

1. Tap the leftmost icon in the upper toolbar and select the photo you want to use as the background from the camera roll.
2. Then tap the leftmost icon in the top toolbar again. Superimpose will ask if you want to load the foreground or background image. Chose "foreground" and select the foreground photo from the camera roll.

Position foreground and background photo



Transform the foreground image in Superimpose

1. Tap the "transform" button in the lower toolbar; then chose either the "rotate" or "resize" button in the upper toolbar.
2. Handles at the edges and sides of the foreground photo will appear. Tap and move the handles to either rotate or resize the foreground photo.
3. Tap and move the foreground photo to reposition it.

I slightly rotated the Eiffel Tower photo and then enlarged it slightly. Due to the slight clockwise rotation of the Eiffel Tower the photo gets a more dramatic look.

I wanted to avoid to make the background show through the fine structure of the Eiffel Tower's pillar. It would have taken me hours to get this done. So I resized the foreground photo slightly and moved it down a few pixels to move the pillar of the Eiffel Tower out of the final photo.

Don't resize the photo too much. A few pixels are okay but if you enlarge it too much, it will become blurry and the final result won't look good anymore.

Note that the dimensions and size of the background photo determine the final size of the photo composition. So if you move a part of the foreground photo out of the boundaries of the background, Superimpose will simply crop the photo to the size of the background photo.

Create a mask in Superimpose

To remove the dull blue sky from the photo with Superimpose we need to create a mask:

Create a mask in Superimpose to replace the background

1. Tap "mask" in the lower toolbar. As the sky has a single color, we can use the magic wand tool. Additionally you can use the eraser or selection tool to manually erase or select the area you want to delete.
2. Next tap the rightmost icon in the top toolbar ("settings") and select the second masking tool from the left ("magic wand tool"). Set the threshold slider to a middle position and chose "smooth". The threshold slider controls how much of the area is selected. The higher the threshold, the more different areas will be selected. The "smooth" option will create a smooth edge for the mask .
3. Then tap the blue sky and watch it magically disappear. If the tap didn't remove the entire blue sky, tap again in other areas of the blue sky until the blue sky completely disappeared.

Finally save the photo to the camera roll:

1. Tap "home" in the lower toolbar again.
2. Then tap the third icon from left in the upper toolbar. It's the sharing icon.
3. Select "photo library".

If the magic wand tool does select the background as desired, try moving the threshold slider either left to decrease the threshold or right to increase the threshold and try again. If this still doesn't product the desired results try the color selection tool or the eraser tool.

The erase tool allows you to manually erase the areas of the foreground photo where you want to see the background shine through.

Step 2: Convert to black and white with Snapseed

 With Snapseed you're able to apply all kinds of enhancements and filters to your photos. Additionally you can crop photos using several presets. To crop the photo with Snapseed:

1. Tap the "+" icon in the upper toolbar and chose the photo you just saved from Superimpose.
2. Swipe through the filters in the lower toolbar until you find "crop". On the left side in the lower toolbar is an icon showing crop lines.
3. Tap it and choose 1:1 as this will give you a square crop.
4. Crop the photo and tap the rightmost arrow in the lower toolbar. This will apply the cropping.

To add more drama to the photo with Snapseed:

1. Swipe through the filters in the lower toolbar again until you find "drama".
2. Tap it; then tap the star icon in the lower toolbar and choose "Dark 1".
3. To apply the filter tap the right arrow in the lower toolbar again.

To convert the photo to black and white with Snapseed

1. Find the black and white filter in the lower toolbar and tap it.
2. Tap the star icon in the lower toolbar and choose "dark".
3. Apply the filter by taping the right arrow in the lower toolbar again.

To save the photo to your camera roll, tap the sharing icon in the upper toolbar.

Step 3: Add the search light with Lenslight

 I used the "searchlight" effect to add the light effect at the top of the Eiffel Tower. There are just three steps to add an effect to a photo with Lenslight:

Add the searchlight with Lenslight

1. Tap "Load Photo" on the Lenslight start screen in the lower toolbar.
2. Then tap "Effects" in the lower toolbar.
3. Swipe left until you find the desired effect; then tap to apply it to your photo.

Once you added an effect, tap and drag the effect to the desired position. Use two fingers to rotate or resize the effect. Tap "edit" in the lower toolbar to change brightness and even the color for the chosen effect.

Tap "layers" in the toolbar at the bottom of the screen to add multiple lighting effects to a single photo. After tapping "layers" tap "add" to add a new layer. Then chose a new effects by tapping "effects" again. Note that all settings you apply via the "edit" command are only applied to the currently selected layer. Don't forget to save your artwork once you're done. Choose "Save" from the top toolbar to export the final photo to your camera roll or share it on Facebook or Twitter right away.

Roundup

You can't influence the weather. That's why I've made a habit to snap stunning cloud moods. Over the years I've built a library of sky photos which I use to enhance boring skies.

The technique from this tutorial helps you replace the background of any photo with Superimpose App [iTunes App Store Link]. It just takes a few minutes. A great sky mood can really enhance your shots.

Keep in mind ...

• ... to use photos with the same orientation for the foreground and background (portrait or landscape).
• ... that the foreground photo should have a background that's suitable for removing. Ideally the background has a consistent color like a clear blue sky.
• ... to always load the background photo first. Remember that you can rotate and resize the foreground photo by tapping "transform"