Filmic Pro has introduced LOGV2 that they claim can give you up to 12 stops on the iPhone XS Max. I reviewed Filmic Pro last year when they first introduced Log recording, and you can read my findings about whether or not it was worth shooting Log on a smartphone.
Filmic Pro LogV2 which is available as part of the Cinematographer Kit (an optional addition when you purchase Filmic Pro) is claimed to take high end mobile video imaging to the next level. The company claims that you can now get up to 2.5 extra stops of dynamic range when using the latest smartphones. LOGV2 works on all iOS, and most Android camera 2 API capable devices.
12 STOPS OF DYNAMIC RANGE
In recent years we have seen the gap between professional cameras and mobile devices continue to close. So many devices are now capable of capturing good results in the right conditions. Filmic Pro claims that LOGV2 enables the newest iPhone XR, XS and XS Max models to exceed 12 stops of total dynamic range at their base ISO. Those claimed figures Would mean that your smartphone has similar dynamic range as cameras such as the BMPCC4K and the Panasonic Lumix GH5s. There is a catch though.
Some of the newer CMOS sensors offer dynamic range that varies with ISO in a bell shaped curve, peaking well past the base ISO. Above you can see how this characteristic works if you were shooting Arri C-Log. The maximum value of the Arri Log C curve depends on the EI value. When you step down the exposure, by one stop for example, the sensor will capture one stop more highlight information. Unfortunately this is not a characteristic of most mobile cameras. With mobile phone sensors, dynamic range peaks at (or very near) the base ISO and falls off rapidly from there. You really do need to be aware that when you are shooting on any mobile phone, that the total dynamic range of the sensor will be much less than a dedicated stills or video camera.
To help you out if you plan on shooting Log on your smartphone, Filmic Pro has also introduced a free LUT Pack that you can download. These LUTs can be used to instantly conform LOG video to Rec.709. They are compatible with Premiere Pro, FCPX, and Davinci Resolve. If you want to edit and grade on mobile device, the Filmic Pro LUTs are available in LumaFusion and VideoLUT on iOS.
HOW DOES FILMIC PRO DELIVER UP TO 2.5 STOPS MORE DYNAMIC RANGE?
LogV2 is the culmination of years of work done on a proprietary computational-imaging module that Filmic Pro internally call “Cubiform”. Cubiform creates a mathematical environment where they can process the luma and chroma of an image with 64-bit precision.
In the case of LogV2, Filmic Pro use this high-precision environment to construct a luma-map from the 8-bit source. Because the luma-map is derived from a flattened 24-bit RGB vector, the resulting fidelity exceeds the 8-bit precision of the individual Red, Green, and Blue elements. This high quality luminance information allows us to reconstruct the gamma of the identity image using a process called ‘gamma vectorization’. After this operation is complete, we map the 64-bit scalar representation of the image into an 8-bit container for publishing to our encoder. The result, as you have seen, is dynamic range and tonal coherence that seemingly bypasses the sparse data-point problems associated with traditional 8-bit gamma augmentations.
With LogV2, we have chosen to abandon linearization and embrace the dynamic nature of the iOS pixel buffer stream. Instead of attempting to perfectly linearize the image, we modify the native gamma with a delta-augment that results in a spline that resembles a tradition log base 2 profile. Because iOS tone mapping is still active, the gamma spline will occasionally take on sigmoid characteristics. LogV2 produces an image with non-linear saturation: it is greatest at the mid-tones and progressively decays as the luminance approaches the back or white points.
FILMIC PRO LOGV2 TECHNICAL OVERVIEW (ANDROID)
On Android devices supporting Gamma Curve Remapping Filmic Pro takes advantage of this tool to provide a custom LOG curve at the sensor level. This allows Filmic Pro to greatly expand the dynamic range of the sensor during the first stages of the camera pipeline. The resolution of this Gamma Curve is device dependent and could vary from 16 to 512 remap points, however in FiLMiC Pro they don’t allow less than 32 to ensure superior quality.
For those Android handsets that do not support Gamma Curve Remapping, Filmic Pro apply the same technique as iOS which is detailed above.
IS IT WORTH SHOOTING LOG ON A SMARTPHONE?
This is going to be interesting to see. When I tested Filmic Pro Version 6 when they first introduced Log recording on smartphones I didn’t find any real benefit in shooting with it. To be honest it was more trouble than it was worth. Hopefully Filmic Pro have done some work with LOGV2 which makes it a lot more usable on smartphones. I’m yet to personally test it, so I still remain skeptical of its benefits. What I will say is Filmic Pro is a great app for getting more professional results out of a smartphone, and you certainly don’t need to use the Log shooting mode to achieve this.