Tips for VR porn producers

Just to explain confusion regarding naming conventions for resolution. Some producers put it as 3840 × 2160 while SLR and others specify it as 2160p.

4K might mean 3840 × 2160, 3840 × 1600, 4096 × 2160, 4096 × 1716, 3996 × 2160 or in our case additionally 3840 x 3840, 4096 x 4096.
2160p has only one meaning - video is exactly 2160 pixels in height

To explain things in more simple way. Resolutions:
1) 4096 × 3072
2) 3656 × 2664
3) 3840 × 2160

"K" abbreviations for this resolutions:
1) 4K
2) 4K
3) 4K

"p" abbreviations for this resolutions:
1) 3072p
2) 2664p
3) 2160p

Must read for everyone getting into VR production https://developers.google.com/vr/jump/rendering-ods-content.pdf

Some quotes:

Omni­directional stereo (ODS) is a projection model for stereo 360 degree videos. It’s designed for VR viewing with a head­mounted display (HMD). ODS uses a special projection format which has the following advantages
● It is panoramic and stereo everywhere—​there are no bad seams or dead zones (except directly above and below the camera, which we will discuss later).
● It's pre­rendered—​like film and video, it plays well on all devices.
● It’s encoded as two video streams—it can be stored, edited, and transmitted using conventional tools.​
This document describes the theory behind ODS and provides instructions and pseudocode to facilitate implementing a virtual ODS camera in your favorite rendering software.
What’s so hard about stereo 360° video? One of the ways our brains achieve stereo vision is by fusing the two images from our eyes. Nearby objects have greater disparity (shift in image position between left and right eyes) than far away objects. Correspondingly, to capture stereo video, we need to capture synchronized video from two cameras set apart at interpupillary distance (IPD), on average about 6.4 cm.
For VR, we need omnidirectional (360 degree) video. Doing this in stereo is not as simple as placing two omnidirectional cameras set apart at IPD. Aside from the issue that the cameras will see each other (in the real world anyway), the problem is that objects lying on the line between the two camera centers will have no disparity. The camera ray geometry would look like the following diagram.
However, in reality, what happens is that your eyes move as you turn your head. This is how real­time CG stereo rendering works. Now imagine you could capture a stereo image for every head orientation, say one pair for every degree.
Limits and distortions Of course, ODS does not exactly reproduce the image seen by the eye. This is because instead of all rays originating at a single point, each ray originates from a slightly different point on the capture circle.
While ODS produces excellent results in general, very close­up objects can cause two problems:
● Line bending—​straight lines in the real world may appear slightly curved in the image.
● Vertical disparity—​after projecting the ODS image to perspective for viewing, some points may project to slightly different y coordinates in left and right eyes. If this effect is severe, the two images will not be fused by our visual system.
The magnitude of the distortion depends on the distance of objects to the camera as well as their angle to the horizon. The distortion is worse for nearby objects and may be quite severe directly above and below the camera. To avoid any issues with distortion, we recommend the following:
● In general, objects should remain at least 60cm from the camera (relative to an IPD of 6.5cm).
● Objects appearing directly above or below the camera should remain at least 3.5m from the camera (relative to an IPD of 6.5cm).

Artistic considerations
ODS is a new medium, and we recommend that artists pay special attention to the following aspects of this medium:
● Content should be omnidirectional—​even if the action is happening in one particular direction, any direction should be viewable. This means the scene must be fully modeled.
● Scale matters—​if an object is 1 unit tall in one scene and 10 in the next, this will be noticed (unless you also change the IPD to match). The lessons learned from 3D movies apply here; however, the stereo effect in VR is much more compelling, so pay extra attention to it.
● Avoid nausea—​camera motion, especially acceleration, can cause considerable nausea. The experience is so immersive that if your vision “feels” something that doesn’t match the rest of your senses, you get an unpleasant physiological response.

Export your videos in equirectangular projection which is default in many players If you use fish-eye projection for some reason, it's better to specify it along with fish-eye type: barrel, small, regular, large, etc. Otherwise your video might look distorted and unexperienced users won't know how to fix it.

Some interesting idea from NVIDIA RoadToVR article: A good camera’s optics contain at least five high quality glass lenses. Unfortunately, that’s heavy, large, and expensive, and you can’t strap the equivalent of two SLR cameras to your head.

This is why many head-mounted displays use a single inexpensive plastic lens per eye. These lenses are light and small, but low quality. To correct for the distortion and chromatic aberration from a simple lens, shaders pre-distort the images by the opposite amounts.

If you have tried to shoot VR, but something does not work please get in touch with content@sexlikereal.com

We would be happy to master VR video from your raw files. We have advanced mastering technology that allows to create state of the art VR video and fix distortions from not perfectly aligned cameras. We can easily fix misalignments, stitching and scaling issues with the power of technology. You can put that video on sale and get immediate feedback from community. In any case this is FREE for you.

If you are just considering VR please get in touch, we would be happy to assist you so you can make success out of it. Just for the record, VR is doing great.

h.264 is compatible with 4K and lower resolutions.

If you would like us to master your videos please do following:
- import all the raw footage (fisheye) to the editing software, also intro/outro video
- do the edit the same you would using any footage, you can use transitions, color grading
- be careful to match edits for both eyes (v1, v2) and that they are synced in time
- sort the audio track so it fits
- that's it for editing part, then save the project file and add it to all the data you used including any overlays you use, like logos to cover/fill the lenses
So in short, it is paramount you do the editing on raw fisheye clips.
Also the intro video isn't required to be as VR video, we will sort this here.

This is also how we agreed we would work with Jim, and tested the workflow on a pilot project, so if they agree we can do a test project with them too, something simple like intro+2scenes+outro