GoPro HERO4 Firmware v05.00 linear FOV Comparison video
The new firmware update adds the new Linear FOV mode to the GoPro HERO4 cameras.
GoPro has released it’s latest firmware packages for their HERO5 (Black & Session) and HERO4 (Black & Silver) cameras. The 01.50 and 05.50 firmware updates add Karma compatibility to all cameras and the HERO5 Black camera alone receives improved support for Auto Upload to GoPro Plus.
More exciting for HERO4 Owners though, is the addition of Linear Field of View (FOV) allowing user to get rid of the fisheye barrel distortion.
While users were already able to use fisheye reduction using GoPro Studio, or other post-processing software. You will now be able to do it in camera (a feature already available in the HERO5 cameras) saving some post-processing time.
A few things to note about the new Linear FOV mode:
- It’s not available in Photo mode
- It is only available in 2.7K and 1080p at the following frame rates 24,30,48,60 (1080p). 24, 30 (2.7K),
- It is also not available on superView modes although it can be used with Protune.
- Some users are also reporting a slight distortion when objects a very close to the camera.
Also keep in mind that like the Medium and Narrow FOVs, Linear FOV is more appropriate for shots with less movement, preferably from a stationary mount or tripod. As the wider FOV lends itself better to immersive and smoother footage when the camera is moving a lot.
This comparison video makes a very good job at showing the difference between all the different FOV modes. As you can see linear and medium mode are very similar with linear mode having the added barrel distortion correction.
— Konrad Iturbe (@konrad_it) October 22, 2016
Barrel Distortion? Wide vs Linear FOV
This type of distortion is commonly seen on wide angle lenses like the GoPro’s, barrel distortion happens because the field of view of the lens is much wider than the size of the image sensor and hence it needs to be “squeezed” to fit. As a result, straight lines are visibly curved inwards, especially towards the extreme edges of the frame. The result is that the image looks distorted around the edges. You can read more about lens distortion here.
GoPro cameras feature feature super wide lenses, perfect for shooting action and high intensity shots, as the wide lens provides a huge field of view. Its fisheye effect also enhances action shots. However, some for some uses like video-logging, or any type of shot where the camera will be static, the linear field of view might be more appropriate.
There are also some disadvantages to Linear FOV, while the lines get straightened and distortion is removed, you also get a much narrower view of whichever scene you are recording, also while you can easily convert the regular wide footage to linear the same doesn’t work on linear so if you accidentally shoot in linear mode you won’t be able to reverse the process.