VR Post Production Workflow Part III:
Adding the Final Touches to Your 360 Video
Once the 360 video is edited and the picture is locked, you can start working on the final details such as text, animations, graphics, tripod removal, color grading and audio mix. For 360 video post production, you need to be extra careful with the elements you bring into your video (2D elements, for example), because you need to make sure they fit the 360 space and are applied correctly.
Final Post-Production Work:
1. Title Cards
Title cards, subtitles, credits or any type of text and/or 2D element that is being introduced into the 360 footage should be adapted to the 360 space, so as not to appear distorted or curved.
Imagine that your panoramic 360 canvas is an A4 paper sheet and that in order for you to look around, you have to connect the opposite edges, forming a cylinder shape. If you write a word in the middle of this paper sheet, it will be curved when you look around from inside the cylinder. To avoid these curved elements, we use a plugin called Skybox Mettle (now that Adobe has VR effects specifically for 2D elements such as text). I find it more reliable to create text on After Effects, render it in PNG (RGB+Alpha) and bring the files into Premiere instead of just applying the VR 2D effect in Premiere. A lot of times the text still looks slightly curved depending on where you are positioning the text element. The same plugin/effect is used for other purposes, such as tripod removal.
2. Tripod Removal
One of the last parts of the post production process is to remove the tripod in all of the shots. You can do it in a couple of different ways:
- You can replace your final shots from the Premiere timeline to an After Effects Composition. This way, any changes you make to the shots in After Effects using Skybox Plugin / VR effects will be automatically modified in Premiere. This option can be quite problematic ata times because either Premiere or After Effects might crash, which increases the final export time in Premiere.
- You can also bring the shots into After Effects, work on tripod removal and then render only one frame of the finalized shot (PNG). This works if you’re working on a static shot where the ground doesn’t move or change colors or lighting. If that is the case, all you have to do is to use this PNG file that you just rendered as a mask in Premiere that will only cover the bottom of the shot where the tripod is located. This will save a lot of time that might otherwise have been spent exporting and rendering shots (as in option 1). In case it’s a moving shot, you can also render the shot without the tripod in After Effects and replace it in Premiere.
Knowing how the tripod removal process works will also help you become a better 360 video shooter. You will understand how important it is to maintain some distance between the 360 camera and the tripod, as well as understand how much time you can save in post-production if you position your camera on a solid surface. Check the examples below:
3. Shot Stabilization
When you have a handheld shot or a drone shot, you will most likely need to stabilize the footage in order to avoid disorientation and nausea for the viewer. This can be done with Autopano Video Pro or plugins such as Skybox Composer and Mocha VR, which also allow you to easily remove the person holding the camera, the rover board or whatever object that can be seen under the camera. Check out the example below with before and after stabilization:
4. Color Grading
You can adjust color scopes in post production using plugins and effects such as ‘lumetri color’ in Premiere/After Effects, mainly because they set the exact exposure values and colors that you need to adjust based on the waveforms. These waveform values also tell you where the discrepancies are in your footage. Being able to balance these scopes in every single shot is very important. Matching shots as a sequence afterwards and fixing other details — such as noise and creating masks to fix specific parts of the clips — are also very important.
Especially in 360 videos, it feels like you are being immersed in a location by mistake if the color disparity is noticeable from one shot to another. The first step is to fix the issues and discrepancies in exposure and color. You can adjust color scopes in post production using plugins and effects such as ‘lumetri color’ in Premiere/After Effects, mainly because they set the exact exposure values and colors that you need to adjust based on the waveforms. These waveform values also tell you where the discrepancies are in your footage. Being able to balance these scopes in every single shot is very important.
Secondly, after the color correction of the shot sequence is consistent, you can choose the style that you wish to convey the story. For example, then you can choose to make your shots cooler or warmer, or you can choose to emphasize certain colors throughout the piece, etc.
A. Basic Color Correction Plugins
Basic color correction can be done in Premiere, utilizing the lumetri color effect or even more advanced (paid) plugins such as Colorista IV, which guides you throughout the color grading process (See image 1). Depending on the 360 camera used, interior shots as well as cloudy and night scenes usually look quite noisy. In order to make your footage look smoother, and for objects to stand out more in the scene, we recommend increasing the sharpness of the image and using a good denoiser plugin.
A great Premiere/After Effects plugin to experiment with is Neat Video, which allows you to denoise the footage and increase the sharpness effectively. However, you should be very careful to not reduce the noise too much that you lose clarity of the details. The secret to a more precise correction is to find the right balance without compromising the outlines and overall shapes of objects and details in the shot.
B. Masking and Compositing
Especially when shooting interior shots in 360 videos that show glimpses of the exterior (see below image), either the inside or the outside is usually overexposed. In order to be able to fix that in post production, it is important to capture what we call “plate shots” — an extra shot that you can later use to mask out the overexposed part of the original short. With the 360 camera positioned exactly in the same spot, the shooter takes two shots — one focused on the content inside the location (so the outside will be overexposed) and another one with the settings changed accordingly to focus on what is going on outside of the location (so the inside will be underexposed). This is only possible with higher end cameras that allow you to play with ISO and luminance of your shot.
Finally, in post production, you can create as many masks as needed to recompose the overexposed areas and color correct these elements separately in a way that the whole scene looks as smooth and clear as possible. You can also create lumetri color masks if you would like to color correct only a specific part of the shot.
C. Spatial Audio Mix
For a truly immersive virtual reality experience, it is essential to invest some time working on mixing spatial audio. Depending on the camera you are using, you will need an external directional audio recorder. However, some cameras like the Nokia Ozo have built in spatial audio recorders to make it easier to capture sound. In any case, during post production, you will need to reorient shots so your story flows more smoothly.
This means that you will also need to adjust the audio for the directions to match. Basic spatial audio orientation can be done in Premiere, but a great software you can use for more advanced sound design is REAPER with The Ambisonic Toolkit. You can also add 2D sound effects to your scene, concentrating sounds in different areas of your 360 video.
This concludes our series taking you through the best virtual reality post-production practices. Thanks for reading along, and if there’s a topic you would love to learn more about, leave a comment below!
