While the activation keys have apparently just started shipping today (at least from Panasonic themselves), since the firmware technically already had V-Log in the software, a number of people got around the $100 activation cost by using Panasonic's own image app. The company has responded to the situation, and understandably, besides taking down the 2.3 firmware with this flaw, they've issued a new update, firmware version 2.4:

Many thanks to those who have recently purchased the LUMIX GH4 V-Log L upgrade. We are aware of an oversight in our Panasonic Image App which allows enabling of V-Log L as a “custom” setting without purchase. This was not our intent, and our apologies for the oversight.

We appreciate the many messages of support for the continuing development of innovative new products and features, and Panasonic intends to stand behind your investment in V-Log L and the LUMIX GH4. Therefore, it’s important to know that future LUMIX GH4 firmware upgrades, including mobile app upgrade pushes, will disable unlicensed activations of V-Log L. In addition, it’s Panasonic’s service policy to upgrade firmware during warranty claims, thereby eliminating unlicensed features. Thank you again for your continued support of Panasonic and the LUMIX G camera system and innovations yet to come.

NOTE:

A new firmware V2.4 will be available starting Sept 17th. Use of the V-Log L workaround associated with firmware Version 2.3 runs the risk of the Zebra Function not working and the Histogram reading improperly.

Panasonic_gh4_v-log_upgrade_process_v2

Though I and many others have called this a hack, it's not really a hack in any way. Flaw is a much better term to describe the situation, as you're not doing anything that the camera and the Panasonic Image App weren't already designed to do. 

This new firmware disables the workaround. If you really want to go the backdoor route and get V-Log for free, the capabilities are out there and Panasonic would have a hard time trying to stop a lot of the uploads of the old 2.3 firmware (and if you've already downloaded the Image App, there's not much they can do there, either). We are not encouraging anyone to do this, and we hope that you'd only use this workaround if you've already purchased the key but are just waiting for it to ship (which has just started as this is being written). 

Here's a guide to install it:

And the written instructions from the video:

  1. Purchase the key code kit DMW-SFU1 from this page. This is not for immediate download, as its kit that will be shipped to you.
  2. Update a fully charged LUMIX GH4 with firmware Version 2.4 from the Global Joint Update Service
  3. Export the camera’s serial number to an SD Memory Card by inserting the SD card into the camera and press Menu - Setup - Activate - Export Serial Code to save serial code as SERIAL.LST file.
  4. Upload the SERIAL.LST file by inserting the SD card into your computer. From the Update Portal Web Page use BROWSE to find and select "SERIAL.LST" file on the SD card. "SERIAL.LST" is saved in folder of PRIVATE - PANA_GRP - PAVC - LUMIX - ACTV - "SERIAL.LST then press Upload to proceed. 
  5. Input "Key Code" from the kit you purchased in "Upgrade Software Key" to this website to get activation code. Alphabet on key code must be big letter to input. Please be careful with misspelling such as 1 "one" and I "big letter of "i"" or 0 "zero" and O "big letter of "o"" Please input key without hyphen "-". Click Register
  6. ACTIVE.LST should auto download from the site. Save this file to the SD card in the folder PRIVATE - PANA_GRP - PAVC - LUMIX - ACTV . 
  7. Insert the SD card into the same fully charged LUMIX GH4 and press Menu - Setup - Activate - Import Activation Code
  8. When prompted power cycle the camera. You will find your new V-LOG L feature under the Menu Photo Style.

If you've already purchased the key, be sure to download the new 2.4 firmware. If the key was purchased from Panasonic, it should have shipped today (or will ship within the next day):

Check out the links below for more, and to buy it if you haven't already.

Panasonic 2.4 Firmware Download

Panasonic V-Log L Activation Code — Panasonic

Panasonic V-Log L Activation Code — B&H

Source: Lumix Lounge

panasonicgh4Panasonic GH4
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