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360° Photography Techniques

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Removing Ghosting in Photoshop

When you enlarge the stitched images, the quality will be visibly low especially when the image contains a moving object such as people, cars or trees. Exposure bracketing is taken at a slightly different position during the shooting process, so ghosting occurs. Ghosting is a moving object in photos which looks faded and transparent like a ghost. In case of HDR, it is difficult to avoid ghosting on people or trees since it takes the same scene several times. In this case, you should edit them on Photoshop.

In the picture below, you can see that there is some difference in brightness or chroma between the right side and the left side of the background. When this happens, find the original image of the right side, copy this part and create a new layer. Adjust the colors of this layer and place mask on it.

Remove any moving objects away from the scene if you can to obtain better quality 360º photos for a 3D virtual tour.
When you enlarge the stitched images, the quality will be visibly low especially when the image contains a moving object. Ghosting is a moving object in photos which looks faded and transparent like a ghost. In this case, you should edit them in Photoshop.

First, find the layer that contains the photo you want to change (the best quality photo), then copy and paste only the part you need.

When you enlarge the stitched images, the quality will be visibly low especially when the image contains a moving object. Ghosting is a moving object in photos which looks faded and transparent like a ghost. In this case, you should edit them in Photoshop.

Select this layer and use Image > Adjustment > Brightness/Contrast or Image > Adjustment > Hue/Saturation to adjust the colors of the background.

When you enlarge the stitched images, the quality will be visibly low especially when the image contains a moving object. Ghosting is a moving object in photos which looks faded and transparent like a ghost. In this case, you should edit them in Photoshop.

Add mask to the layer you created and fill it with black.

When the ghosting which is a moving object that looks faded and transparent like a ghost occurs, you can manually remove it using layers in photoshop.

By selecting the mask and coloring it using a white brush, you can clear the ghost image problem. Repeat this process until you remove all ghost images.

Remove any moving objects away from the scene if you can to obtain better quality 360º photos for a 3D virtual tour.

Color Adjustment

You can adjust the tone and color of photos after the stitching process. Open Photoshop and go to Image -> Adjustment. Go to Preset and use Linear Contrast or Medium Contrast to increase contrast. You can add blue or orange by using Image -> Adjustments -> Photo Filter if needed.

You can adjust the tone and color of photos after the stitching process to get a better quality.

Summary (Bracketing Shooting and Image Process)

- Equipments Needed to Take a 360º Photo

Nikon D810 for a body, Samyang 8mm fisheye for a lens, Manfrotto for a tripod, Horusbennu for rotator and wireless shutter release are used. Refer to this post for more details.

- Camera Setting When Shooting a 360º Photo

  • Storage mode: In RAW mode, it’s easy to control the quality of the photo but it can take up too much capacity, so if you are going to shoot many photos, this method is not recommended. If you save the photos in JPEG, they are compressed to a much smaller size so it can be used in various software.
  • Shooting Mode: Set in M. Set the median exposure and take photos using AE bracketing mode. Take 5 photos at each exposure value from -2 to +2 (-2, -1, 0, +1, +2). You can take fewer photos (3 photos) or more (7 photos) depending on the quality of photos you want to achieve.
  • White Balance Setting: Depending on the weather, select one among the presets. Never use auto mode. If you set in auto, the white balance and color will change in every photo. These differences may cause stitching errors or interrupt seamless stitching showing a line on the photo when you stitch them to a 360º photo.
  • Distance Setting: Set in Manual. When you set in F8, you can shoot infinitely but the best is setting the distance, taking into account the objects within the frame.
  • AEB: Shoot in AEB (Auto Exposure Bracketing) in every spot and go to HDR (High Dynamic Range), more specifically shoot in exposure fusion method. all must be set in manual. You can get the best result when you take all images under the same condition/settings.
  • The Number of Photos: The most important thing when taking a 360º photo is taking images from all directions. Shooting as much as possible is what’s ideal but it takes up a lot of storage capacity so you should shoot efficiently. If you use 8mm lens and Nikon D810, shoot 4 images tilting the camera 5º upward. Keep in mind that this method aforementioned doesn’t cover the ground area. You can hide the empty area on the ground by inserting a nadir photo or blending the area in Photoshop.
  • Stitching: Import all the photos in PTGui. Apply the HDR process with exposure fusion method and set the pixel at 10,000 x 5,000. For more details, click here.

Shooting Tips

1. Remove any moving objects away from the scene if you can.

A moving object may hamper the photo quality even though the software adjusts them to some degree during the process. This is common if you capture movements using bracketing method. The objects appear like a ghost or transparent double images in areas of the panoramic photos where two adjacent photos are overlapped.

Some photo stitching programs have a blend path that automatically blends frames together and removes ghosts. Also, you can manually erase it in Photoshop. However, the best way is to still be aware of the movement when you capture the scene.

Remove any moving objects away from the scene if you can to obtain better quality 360º photos for a 3D virtual tour.

2. Don’t get too close to objects.

If you have an object located too close to the camera, distortion may occur in the panoramic photo. Also, if objects such as walls are too close to the camera, the photos can’t obtain sufficient overlaps which can trigger an error during stitching.

A common mistake, especially in real estate when trying to take photos to make the room appear bigger, is to take photos from a corner.

A common mistake especially in real estate when trying to take photos to make the room appear bigger is to take photos from a corner. If you take photos too close to walls it has a high chance to have an error stitching error.

3. Avoid grounds with cross or striped pattern.

When selecting a shooting site, avoid grounds with cross or striped pattern. It can lower photo quality since it is difficult to have these lines meet when the photos are later stitched. The best areas are lawn or grounds with no visual and physical obstruction.

4. Avoid the sun when taking photos.

If you take photos outdoor, consider the shadow and shoot it within the shadow so that traces of the shooter doesn’t appear in the photo. Normally, a wide-angle lens which can capture a wider range of a scene is used for panoramic photos, so there’s a higher chance of containing a shooter’s shadow.

5. If it’s sunny, shoot at AEB (Auto Exposure Bracketing) mode.

Especially on a sunny day, even if you’ve adjusted the correct median exposure following the instructions above, the photo may still appear too dark or too bright. When you adjust the exposure of dark areas, details on dark areas disappear and vice versa. In this case, the best possible way is to shoot at AEB: Auto Exposure Bracketing mode and stitch the photos with HDR. Note that HDR process is only available on PTGui Pro version.

6. Save your photos in RAW format.

Even though the size of the RAW file is bigger than JPEG, you can achieve better quality because it doesn’t compress the image which inevitably lowers the quality. The RAW format is less universally readable compared to JPEG format but it’s more useful when you import photos to other photo editing programs such as Photoshop and Lightroom. In these programs, you can export from RAW to DNG to keep the image quality high.

7. Keep the same exposure for all photos.

If you set the exposure to automatic, each photo may have different levels of exposure which can lower the quality of the panoramic photo.

The best way is manually setting the camera. DSLR cameras usually have ‘M’ mode which allows users to set the aperture or shutter speed. In this mode, adjust the exposure in the middle and set the aperture and shutter speed so not to overexpose or underexpose. If your camera doesn’t have the manual mode, use the AE-lock function which fixes the shutter and aperture. A narrow aperture(F8~11) is recommended to achieve a deeper DoF which consequently brings clear photos with wide focus.

When taking 360º photos for a 3D virtual tour, try to keep the same exposure for all photos. You can adjust the brightness of the photo in other post photo editing program. Set your camera to manual mode and adjust the exposure in the middle.

8. Save the photo in PSD format in PTGui to erase or edit it in Photoshop.

There are various stitching programs available for use. I’ll show you how to process 360º panoramas with PTGui program. This program is very convenient since it can process most photos automatically.

Sometimes, you have a moving object like a car or a person while shooting. So you may have half of the photos with this object while the rest don’t. In this case, you can remove the unwanted object from Photoshop. In order to do this, you should save the final version as a Photoshop file. On the Create Panorama tab, activate Photoshop (.psd) and Blended and Layers options then save it.

There are devices that take 360º photos with a click of a shutter, but in most cases, we take several photos, partially overlapped, with an ordinary camera and use a stitching software to produce a panoramic photo.

A simple explanation for taking a 360º photo is to take several photos of about 30% or more overlapped horizontally (360º) or vertically (90º+90º), at a fixed position.

Shown below is an example of photos taken horizontally, vertically or at 45º. The number of photos you take depends on which kind of lens you use. If the angle of view is narrow, take many photos and if you use a wide-angle lens or fisheye lens, you can take fewer photos.

You can use various stitching programs to combine these photos and create a big photo with a length to width ratio of 2:1. Using a panoramic photo viewer, you can rotate the photo in all directions.

Principles of a 360º Photo

This photo is composed of several photos (about 10 photos).

You need to cover the entire surrounding of the spot ensuring each photo has a sufficient overlap to get a 360º photo. Depending on your camera and lens, you may need more than 4 photos to cover 360º.

After taking several photos overlapped, combine them into one image with a computer program.

To take a panoramic photo, you need a camera that supports panorama function. As shown below, such camera is made with different methods from an ordinary camera. It has a slit type lens system, so as a slit revolve, a line of light is recorded. Ordinary camera records a full shot at once.

This is the reason why a panoramic photo and an ordinary photo are taken using different methods.

A panoramic photo projects the images onto the surface of a cylinder, then unrolls the cylinder to make a flat plane, while a standard non-panoramic photo displays the images on a flat plane directly. If there is a rectangular object (ex. building), an ordinary photo shows it as a flat rectangle while a panoramic photo shows a straight vertical line and a curved horizontal line.

You can’t create a 360º photo by simply stitching ordinary photos together. It is possible but there is a huge chance the quality will not be as seamless as the original panoramic photo.

To transform an ordinary photo into a panoramic one, you should change the projection method. Change to panoramic mode first, and stitch the photos together.

Rules of Taking a Panoramic Photo

To take a panoramic photo, you should keep a few things in mind. The most important step is to keep a steady surface of rotation. You should fix the camera on a single axis and move it towards one direction, from one side to the other. The surface of rotation can be a horizontal line, vertical line or diagonal line. No matter which line you choose, you should fix the camera on one axis to prevent it from shaking.

Second, the photos you take should be partially overlapped. Overlapped photos will help the program identify the same spots to process. The best overlap ratio is about 20~50%. More than 50% overlap is not necessary and will only make the process complicated. Less than 20% overlap may cause errors. At least 10% overlap is essential to create a seamless panoramic photo.

To take a panoramic photo accurately, you should use a tripod to keep a steady surface of rotation.

Install the tripod and camera first. Do not fully tighten them. Spin the camera on the supporting surface to check whether the camera can smoothly move from side to side.

Take a photo at the first position, slightly rotate the camera to the right and take another photo.

Repeat this process until the end. If you rotate the camera to the left, you should change the order when you edit. The photos should be partially overlapped.

Make sure not to change the position of the camera on the tripod while capturing the scene. If you set the camera vertically you must maintain the position while capturing. Also, if the tripod is not set properly, take photos again to ensure you get clear images.

As digital cameras have evolved over the years, wireless connectivity and large resolution are now the norm. Nearly all cameras now contain both manual and automatic modes with high-tech camera sensors that allow you to take professional-grade photos. Yet when it comes to 360º photos, despite the deployment of several auto-related advancements, nothing still compares to the quality that results from crafting photos by setting one’s camera’s dial. When taking 360º photos, you need to cover all surroundings by rotating your camera and maintaining a certain setting to achieve a seamless 360º photo when all the images are stitched together. If you take photos with an auto mode, the camera settings are ever changing depending on the condition of the scene, such as the amount of light. This can cause stitch lines, the connection of two photos that appear unmatched and disconnected, hence why it is crucial to set the camera manually before taking photos.

There are 5 components you can set: ISO, Exposure, White Balance, Focus, and Aperture.

1) ISO

ISO determines the sensitivity of a CCD (Charge-Coupled Device) in a camera to light. If you set the camera to Auto mode, the camera automatically adjusts the ISO. However if the Auto ISO has different exposure value for every photo then it can cause discontinuities in brightness across stitching images and can cause stitchlines. Therefore, you need to set it manually so the images can be stitched seamlessly. Every camera has a different range of ISO values (sometimes called ISO speed). A higher ISO allows for a faster exposure period which can reduce image blur and reduce shooting times in low-light environments. The drawback to increasing the ISO is that it makes the picture noisier causing the photo to appear grainy.

When is the right time to use low or high ISO? Using a low ISO value is recommended to reduce noise but if you need to reduce shutter time then ISO 1600 is the highest value recommended. When you are in a space with ample amount of light coming in, it is ideal to use a low ISO value as well as increasing ISO value if there is not enough light for the camera to capture.

Camera Setting for real estate 3D virtual tour - ISO Comparison: Low ISO vs High ISO

2) Exposure

Usually dark and bright areas coexist in the same scene. You need to set your camera to the correct median exposure to balance the light or balance the lights and darks. If your median exposure is too dark, the brighter exposure is not going to be bright enough to capture all of the detail in the shadows. On the other hand, if your median exposure is too bright, your darker exposure is not dark enough to capture all details in the highlights. As a consequence, you get a washed-out image lacking in easily distinguishable details.

Set exposure with your back to the sun the sun when you take photos outdoors. When you take indoor photos, find a proper spot that has moderate lighting (not too bright or dark) and set the median exposure. Keep in mind that you must maintain the same exposure value while covering one 360º photo. If you suddenly change the value, it creates a stitching line between two photos when you stitched them together.
If a scene is too dark or bright, you can use bracketing method which will be talked about in one of our future blog posts, or you can adjust the brightness in other programs such as Photoshop and Lightroom after stitching the photos. When you set the exposure, take several photos as test to find the correct median exposure.

Camera Setting for real estate 3D virtual tour - Set the median exposure

(A) Dark area    (B) The area to set the median exposure    (C) Overly bright area

Camera Setting for real estate 3D virtual tour - When median exposure is too bright

When median exposure is too bright

Camera Setting for real estate 3D virtual tour - When median exposure is too dark

When median exposure is too dark

3) White Balance

After setting the exposure, set the white balance. The white balance affects the general color or temperature of the scene. Temperature ranges from the very cool light of a blue sky down to the very warm light of a candle. Many digital cameras have automatic and semi-automatic modes to help you make the adjustments such as Auto, Tungsten, Fluorescent, Daylight/Sunny, Cloudy, Flash and Shade mode. You can get an accurate result using the above presets but if you want to set your own white balance value, you need to manually adjust the white balance. Take one photo and then hold up a piece of white paper to your camera to tell it what color white is. For beginners, we suggest using auto mode when setting the white balance. To set manually, import the image to a post-processing software such as Photoshop or Lightroom and pick a spot using a white balance picker. The white balance will be automatically adjusted.

If you are not able to set the white balance, save the photos in RAW format and adjust it in other programs such as Photoshop, Lightroom or Capture One.

Camera Setting for real estate 3D virtual tour - How to set White Balance

4) Focus

You need to anchor your camera focus to a certain distance. Before you set the focus, set the correct aperture that is one or two levels down from the maximum aperture size (F/8 is recommended). Once you’re done with this, the depth of field (DOF) called focus range or effective focus range will become deeper achieving a clear image as a result.
Setting the focus manually is essential to take 360º photos. If you set it in auto mode, the focus will keep changing at each angle which triggers errors when you stitch them to a 360º photo.

First, change the AF/MF switch to MF (manual focus). Next, turn the smaller focal ring all the way to the left, until you see the infinity symbol. That way you can set your lens to infinity mode and it helps you to obtain images with the same focus for every angle. To make it more accurate, you can take each photo with different angles, then compare the results on your PC to choose the best focus for the site.

Camera Setting for real estate 3D virtual tour - How to set the focus

When the focus is not set

Camera Setting for real estate 3D virtual tour - How to set the focus

When the focus is set

5) Aperture

Aperture is marked with an A on Nikon and Sony cameras, and AV on Canon. Aperture relates to the depth of field (DOF) which is the distance between the nearest and farthest objects in a scene. Simply put, DOF controls how much of the photo is in focus. With a change in aperture, you can manipulate the depth of field to your desired effect. For instance, if the aperture size is f/2 you get a blurred background of the image as the depth of field becomes shallow. When it comes to a 360º photo, you need to adjust the aperture to a higher number so that all objects in the scene are absolutely in focus. One or two level down from the maximum aperture value (small aperture means deeper DoF and wider focus) is recommended because the maximum value are not at their best at extreme aperture because the diffraction of light can cause a drop in sharpness and make your photo susceptible to long exposure noise and motion blur. For example, if the maximum aperture aperture value of your camera is f/22, we recommend f/8 or f/11 to get the best quality image.

Camera Setting for real estate 3D virtual tour - How to set the aperture
As soon as an object falls out of this range, it begins to lose focus to an accelerating degree the farther out of the zone it falls.

Tips when choosing a DSLR camera for 360º photo

  • Choose a camera body that is compatible with various lens and allows you to manually change camera setting.
  • Choose a camera body that connects to a remote shutter release which helps you take photos stably.