How to make a panorama or video__ picture needed for VR

"TOC" summary

For the current VR technology, the effect of settling the mud chamber is presented.
① relies on Unity3d to build 3d environment
② rely on panoramic images or panoramic video to achieve panoramic results here is not the first method, mainly say how to use a fish eye camera or panoramic camera to get our VR to use the  degree of pictures and videos before we know, we need to shoot skills, And some of the camera techniques used to do some research.
get to the point.

Take our curiosity, and our questions to open our journey to get a degree picture. Fish Eye Lens

What is the fish eye lens, let's take a look at the following picture, is not the same as the usual picture.

What is a fish eye camera: To make  panoramic photographs, fisheye lenses are essential photographic equipment for panoramic photographers. The focal lengths of our common fisheye lenses are usually 8mm to 15mm. The choice of fisheye lenses for panoramic shots is mainly due to the fact that the fisheye lens takes a larger view of a single photograph, thus reducing the number of photos of the mosaic panoramic photos. Generally, the use of 8mm fisheye lens, panoramic photography less than four shots can be used, 15mm fisheye lenses,panoramic photography on the whole machine on the most shooting up to less than 10. In short: the use of short focus to obtain large viewing angle, with fewer shots of the Mosaic panorama, reduce the amount of filming and later splicing time. The longer the lens focus, the narrower the perspective. 8mm lens, diagonal angle of view reached 180 degrees. Fish eye lens is considered to be a degree panorama of the sharp weapon, because it has a wide range of perspectives, shooting efficiency, and the quality is basically to meet the network panoramic view.

The difference between a fisheye lens and an ordinary super wide-angle mirror is the size of the angle of view and whether the distortion of the image is corrected. The 13 mm wide-angle lens has a view angle of only 118, while a 17 mm fisheye lens has a field angle of 180. Super Wide angle and other lenses, trying to correct the edge of the screen distortion, and strive to make the picture and the object of the same. And the fish eye lens is intentionally retains the image the barrel distortion, uses to exaggerate its distortion effect, takes out the picture in addition to the center part, all other lines all will turn the curved curve.

There are two basic types of fish eye lenses

Round fisheye Lens: A circular image with the diameter of the frame width of the film produced on the negative.

Diagonal Fisheye Lens: A rectangular deformable image that produces a full frame of the film. VR Video Lens

As the panorama continues to appear in the eyes of the people, VR panorama cameras have been launched, many virtual reality enterprises have begun to target the VR panorama content.

But it's never easy to take a VR panorama video. Unlike traditional video-capture techniques, you should be aware of several issues when taking VR Panorama video.

First, the choice of panoramic camera. To take a video that applies to a VR device is not as simple as it might seem, the VR three-dimensional environment requires a video-recording device to be photographed in  degrees, so pay special attention to the choice of a panoramic camera.

Secondly, it is also important to find a camera seat on the panorama. A location may not be suitable for all movements, so you need to select multiple seats, hanging on the rocker or hanging in the camera car, how to move and so on need to consider. Within the scope of the panoramic camera lens, all personnel (including the director) must be avoided, the scene can not be left behind the story not related to things. In addition, virtual reality cameras cannot be located in locations that can cause security problems. Finding the best seat for the audience is the key to the learning of the camera master.

As far as the current Panorama camera technology is concerned, the zoom on VR panoramic video is not very good, and the camera depth and focus positioning become a big problem. So the camera master to find the best position, you need to locate the camera, so that the audience will not feel dizzy and uncomfortable viewing.

The optimal height of a VR panorama camera needs to be tested before taking VR Panorama video. Not too high, otherwise the audience can only overlook the performers, not too low, otherwise the performer's facial expression can not see. In addition, the producer must find the same height that shows the dancers ' feet, the scene cameraman and the audience.

For VR Panorama video, special attention should be paid to the lighting problem. Traditional video requires lighting appearances, and everything in a degree panoramic video needs attention. How to work with the lighting technical guidance, to produce a camera for the center of the radius of the lighting, so that viewers to watch their choice of things and do not interfere with on-site entertainment, very important.

One issue that deserves special attention is the background music of VR Panorama video, which can bring viewers into the perfect Panorama world. So the fusion of 2D music and stereo music needs to be tested. how does a normal camera take a panoramic view?

720-degree panorama relatively professional, the need for a wide-angle lens, 4-6 photos, and degree panorama does not require special cameras and PTZ can be completed, even the phone can be completed.

First, the handheld camera, to keep it on a horizontal line, after taking the first photo, remember the right part of the viewfinder, and when you take the next one, the left side of the viewfinder must overlap with the previous one, preferably 1/4 of the whole picture, so that you can rotate degrees to make a lap, The entire process camera is kept on a horizontal line, and the last photo is coincident with the first, so a group of photos is finished.

The camera's horizontal picture is about 6-8 shots, and the camera's vertical photo shoot is about 11-13 shots. Finally, using the common flattening software, the degree panoramic picture is assembled, and the Panorama software can be used to view the dynamic panoramic photos on the computer, and can also be sent to the Internet. How do I get a high quality panoramic picture?

Camera must be accurately and reliably positioned:

Since the camera has a visual angle of less than degrees, multiple photos must be taken to record full view image information. In order to allow multiple photos to be seamlessly connected to a panoramic projection image, the camera must be accurately and reliably positioned, the center point of rotation should be fixed on the middle node of the lens used, and the photo overlap position should be accurate, compared with the previous manual positioning device , now has a dedicated automatic rotary positioning shooting equipment available for purchase, can be accurately positioned shooting. Many enthusiasts use only the tripod to make a panoramic picture of the vision, and for example, indoor close-up shooting, stitching will become very difficult, visible up and down heaven and earth in three-dimensional panoramic shooting, must use a node of the rotating cloud platform.

The best choice is the ultra wide-angle lens:

To take a full degree panoramic picture, the longer the camera lens is smaller, the more photos are taken and the more complex the post-processing becomes. Another advantage of the wide-angle lens is that the scene is deep, the face of a variety of different distances to the panorama can be taken into account, it is best to choose less than 18MM fish eye lens. For example, the use of 18MM lenses need to take 8-10 shots (the photos should be appropriate overlap), and the choice of 8MM fisheye lens only take 3-5 pictures. Of course, you can now buy a degree digital turnaround by clicking a shutter, but the price is very expensive.

Framing and using:

Framing not only to take into account the level in all directions, but also to take into account the sky and the site, spherical and cubic panoramic sky and site of the ingenious framing can be integrated into the three-dimensional environment effect. Light is the difficulty of panoramic shooting, because it is degrees of shooting, you can not avoid the backlight and direct sunlight, contrast the big difficult to control, this is the difference with ordinary photography. However, because panoramic photography is photography, so the photographer's use of light and the basic skills of shooting, all can be used in the panoramic shot and reflected.

Camera Basic settings:

Turn off automatic focus, turn off automatic white balance, turn off the flash, and manually fix exposure values after metering to ensure consistent photo exposure and set the same quality and resolution. Each adjacent photo overlap area is not less than 30%, but also in the shortest possible time to complete the shooting, so as to meet the automatic splicing software identification requirements

Do you have any knowledge of the shooting techniques needed for VR, and then I'll follow up on how to correct the fisheye picture.