When Matthew Allard ACS recently reported on NewsShooter that he had seen the V-Log profile in operation on a Japanese photographer’s Panasonic Lumix GH4 at Inter BEE hopes were raised that V-Log would make it into the popular hybrid camera’s December 2014 firmware update.
Allard then amended his post to report that a Panasonic spokesperson said that V-Log will not be in the December firmware releases and that “they are just testing it”. So what is V-Log and why was Allard and many other GH4 owners – yours truly included – so excited at the prospect that it may arrive in a future firmware update?
Gamma Curves, Picture Styles and Dynamic Ranges
Panasonic’s V-Log is a logarithmic gamma curve and Alister Chapman, whom I first encountered when researching the Sony A7S camera’s own S-Log2, does a great job expounding on what gamma curves are and when they are useful in Choosing the right gamma curve. If only there were equally good resources on all aspects of getting the best color and dynamic range response out of our cameras!
Gamma curves are often selected via your camera’s picture style settings. Sony's A7S is an example. The A7S manual proved to be marginally useful on this issue but I found articles like this one at SonyAlphaLab were illuminating.
The value of changing your camera's color response by using picture styles, aka picture profiles, in DSLR moviemaking came to light in the early days of the DSLR revolution when Technicolor first released its free CineStyle profile “that boosts the dynamic range in your camera” – so long as your camera was a Canon EOS DSLR.
More recently Panasonic’s VariCam 35 high-end movie production camera updated the Japanese company’s VariCam line with “14+ stops of latitude, a wide dynamic range and color gamut approaching film cameras” as well as being “equipped with a full-size 4K image sensor”.
V-Log & V-Gamut in Panasonic’s VariCam 35
The “VariCam Look” as Panasonic is calling it, is apparently created by combining V-Log with V-Gamut which, according to Panasonic, gives the VariCam 35 “a wider color gamut than that of film”.
The wider the color gamut, the larger the color space, the more colors you have to work with and the closer to the vast range of colors the human eye senses in the world around us. Starting off with a wide color gamut via V-Gamut and other color gamuts settings appears to be a distinct advantage in moviemaking.
Similarly, choosing a wider color space like Adobe RGB instead of the more limited color set of sRGB offers more colors to work with when shooting stills. Converting AdobeRGB raw files into ProPhoto RGB 16-bit via raw processing software maintains a large set of colors to work with until exporting your publication files as JPEGs.
Back to V-Log which Panasonic tells us extends the dynamic range of the original VariCam’s ‘F-REC’ gamma curve and “is capable of recording the 14+ stops of dynamic range… and enhances grading flexibility. …The wide dynamic range assures accurate image rendering over the entire image area, from dark parts to highlights.”
Panasonic has demonstrated the benefits of V-Log in combination with V-Gamut with its movie introducing the VariCam 35, VariCam 35 First Look: 4K. View it in 4K if you have the bandwidth and on an Apple iMac with Retina 5K Display if you have one!
I can only assume that V-Log was used with V-Gamut given the point of the movie is to show the camera off at its very best. So far I have not found footage showing V-Log on its own or with another color gamut for the sake of comparison.
This begs the as-yet unanswerable question, if V-log does appear on the GH4 will it also come with V-Gamut? If and when it does, then that will be the time to break out the party hats and whistles.
The Atomos-Panasonic Relationship Begins
- With this firmware, time code and RSS (Recording Start/Stop) signal can be embedded to the HDMI output signal*. *Available when DMC-GH4 or DMW-YAGH are connected with the products of Atomos Global Pty. Ltd. or the products complying with the extended specifications of Atomos Global Pty. Ltd..
- FHD at 30p/25p native output via HDMI is available while recording video in FHD at 30p/25p.
- HD at 30PsF (Over 60i) / 25PsF (Over 50i) output via SDI is available while recording video in FHD at 30p/25p. *When DMW-YAGH is used for SDI output.
A reminder on these never-ending acronyms. FHD is 1920 pixels x 1080 pixels. HD is 1280 pixels x 720 pixels. UHD aka UHD 4K is 3840 pixels x 2160 pixels while 4K aka DCI 4K is 4096 pixels x 2160 pixels.
There will certainly be an external recorder/monitor in my future especially one that allows me to check what I am shooting with 3D LUTs applied. For now though my project funding and backpack weight budgets mean I will be an observer, not a player, of the outcome of December's firmware update.
A future update that will include V-log and V-Gamut, now that is something I am holding out high hopes for. The Panasonic Lumix GH4 really will earn its stripes as The Swiss Army Knife of Hybrid Cameras, able to hold its own by outputting footage as eminently gradable as that from cameras like the Panasonic VariCam 35 and, for that matter, Sony’s A7S.
(cover photo credit: snap from Karin Gottschalk)