Creative Workarounds in Remote and Freezing Conditions: Steven Sun on “The Battle at Lake Changjin”

The Chinese film “The Battle at Lake Changjin,” tells the story of The People’s Volunteer Army (PVA) fighting the enemy at Lake Changjin under freezing conditions- a turning point in the Korean War.

In this interview, DIT Steven Sun takes us behind the scenes and shares some exclusive production insights on how he relied on the features of Silverstack XT, Offload Manager, and some creative workarounds to support their workflow while filming in remote locations under extreme weather conditions.

First of all, thank you for sharing some insights into your productions with us. Can you tell us a bit about yourself and your work?

My name is Steven Sun and I’m a Beijing-based Colorist and Digital Imaging Technician (DIT) with Beijing Digital Photosynthesis Technology Co. I first entered the film industry as a camera assistant, then became a DIT in 2016 and joined Dimension Plus Technology (D-Plus). In recent years, I’ve worked as a DIT on many films including the following:

• Detective Dee: The Four Heavenly Kings 3D
• The Capitan
• Chinese Doctors
• The Battle at Lake Changjin
• The Battle at Lake 2: Watergate Bridge

I also provide post-production and color-grading services for short films and commercials.

What kind of projects are you/is the company you work for (D-Plus) usually involved with?

Currently, D-Plus provides services for Stereo 3D shooting, live broadcasts, feature film and TV productions, DITs, post-editing, and color-grading. Our DITs are officially QCP certified with QTake, as we were the first team in China to use QTake. In 2010, the company worked on the production of the 3D stereoscopic film Flying Swords of Dragon Gate, and we were responsible for shooting in 3D, providing DIT services, QTake, and managing other parts of the film. Since then, D-Plus has provided film and TV technology-based services for more than thirty films and TV shows. We’re now also getting involved with the virtual production-related business.

You recently worked on the very successful movie called The Battle at Lake Changjin and its sequel, The Battle at Lake 2: Watergate Bridge. Can you tell us a bit about these projects?

D-Plus was involved in the production of The Battle at Lake Changjin from 2019-2020, providing DIT and video assistance services while on location in Dadong City, Liaoning Province. The crew spent about a month shooting in harsh weather conditions with an average temperature of -30°C. We helped the camera department select equipment, and assisted with color grading tests for the day-for-night scenes. After several tests, we designed creative looks for reference and submitted them to the post-production department.

The shooting environment was mostly snow-covered mountains and frozen lakes, so it was difficult to transport equipment at first. So, in order to meet the director’s fast-paced shooting requirements, keep the director’s video village close by to the shooting site, and overall improve the efficiency of the shoot, we developed our own portable V-mount battery-powered QTake HDx4, which greatly reduced the time it took to transport equipment.

For the production of The Battle at Lake Changjin, which started in late 2020 the D-Plus team provided DIT services for both A and B sets directed by Hark Tsui. There were a total of 11 DITs involved throughout the entire process including pre and post-production. Among the DITs, Stego Zhang, Irish Gao, and I had previously worked together on several other projects:

• Detective Dee
• The Taking of Tiger Mountain
• The Thousand Faces of Dunjia
• The Bravest
• The Capitan

With so many varying needs for this project, we optimized the workflow as much as possible while ensuring data security, and enhancing training for members to improve efficiency internally and collaboration externally.

Which cameras were used on these projects?

For The Battle at Lake Chanjin, there were two units, A and B, shooting simultaneously under the supervision of DPs Gao Hu and Kenny Tse. The main cameras used were RED Monstro 8K and RED Gemini 5K. The aerial cameras used were RED Helium 8K and DJI Zenmuse X7. In addition, we used ZCAM E2-F8, ZCAM E2-F6, and Sony A7S3 with a Ninja V recorder. A total of 14 cameras were used in special environments (e.g. cramped and closed areas, or scenes with explosions and burns).

Why did you decide to use Silverstack XT and Offload Manager?

D-Plus uses Silverstack XT and Offload Manager on a yearly subscription basis. I like that Silverstack XT has a professional video scope, SDI output screen, and more supported RAW file formats than regular Silverstack. Also, it can do most of the audio and video material security backup and metadata management that most film productions require.

In projects with a lot of cameras and a large amount of footage, there are multiple units (A, B, and C) with multiple cameras shooting at different locations all at the same time. Each unit needs multiple computers and disk arrays to back up a large amount of video footage quickly and safely on set which is why we also use Offload Manager.

It helps us with the initial secure backup of audio and video footage on set and then imports the daily project files to Silverstack XT for metadata management and secondary backup. Since our needs for hardware are ever-changing, we need adaptable and reliable software all year-round which is why the subscription model for Silverstack XT and Offload Manager best suit our needs. We also use Silverstack Lab on occasion when the task at hand requires it.

Can you please briefly describe your on-set workflow on these productions? For which aspects of your work did you use Silverstack XT and Offload Manager?

During the production of The Battle at Lake Changjin, the DITs were responsible for color management, DMT data management, quality check (QC), and QTake Assist.

While shooting, the two units (A and B) used Silverstack XT and Areca disk arrays to double back up the footage and metadata with a safe yet high-speed checksum method. Back in the resident server room. both units backed up footage to multiple destinations safely and completely. The data manager created summaries with the metadata from Qtake, field notes, and the camera reports in Silversatck XT.

Then, using DaVinci Resolve Studio, completed camera color matching, generated proxy footage, and did a 4K quality check in real time. We exported and distributed the customized and comprehensive DIT reports at the end of the day, and all 4 backups of audio footage, video footage, and associated metadata were delivered safely and completely.

The DITs monitoring the video footage in real-time performed quality checks on focus and exposure with tools like False color, Waveform, and LUT through the QTake grade and scope modules. DITs could also output the scopes screen to other monitors on set to share with the DP. In the DIT room, the data manager used a computer with RED ROCKET-X to perform high-quality real-time 4K quality checks on 8K RAW footage, unlike on-set quality checks on 1080P 422 SDI video signals. We also used a Color-corrected 55″ SONY 4K TV to visually check the picture detail and focus, then used Silverstack XT to distribute the QC results across multiple departments.

How was your overall experience working with Silverstack XT and Offload Manager? Were there any features that you used frequently or like in particular?

Silverstack XT and Offload Manager have great feature design, stability, and metadata management capabilities that I can’t live without. I often used the pause feature to stop the offload while we were on location with rough weather conditions and then resumed the offload later once we had left so I could do it efficiently and safely.

My favorite feature is that I can easily import or export metadata from other software, for example, I can easily import metadata from QTake to reduce repetitive work, and I also can quickly export the corresponding metadata needed by various software.

Another Pomfort application that I really like is ShotHub. It makes the information transfer across sets so much more efficient. The addition to the cloud function changed the previous local-based process, which is especially important for remote team shooting. Unfortunately, while shooting The Battle at Lake Changjin, the ShotHub function was just taking shape, and most of the filming locations were in remote areas with no signal at the time. Therefore, we couldn’t use ShotHub. If there ever were a ShotHub server set up in Hong Kong, it would make the experience of using ShotHub in China much smoother and more stable.

Were there any particularly challenging situations or setups on these projects? How did you address them?

Small cameras are often used for special shooting, but the filenames of these cameras do not conform to material naming conventions, thus causing some problems in post-production. In the past, we used to do renaming outside of Silverstack software. For example, during the production of The Battle at Lake Changjin, the video file names in A7S3 and Atomos Ninja V did not conform to the naming convention of the footage, so the files needed to be renamed. Due to the large number of files, we designed the Rename automation process to solve this problem. Now, the new version of Silverstack XT supports renaming when offloading MP4/MOV files, This is a great feature that we’re very excited about.

Another challenging situation we ran into was that the ProRes RAW recorded by Atomos Ninja V needed to be transcoded and converted into the correct color space, but DaVinci Resolve Studio could not handle ProRes RAW. We tested the transcoding of Scratch’s ProRes RAW and although it could meet the transcoding needs, there was not much ProRes RAW footage in this shoot. Considering factors like the data manager’s workflow, we finally chose Compressor to complete the color space conversion and batch transcoding of ProRes RAW, which was more simple and efficient.

Finally, we were shooting in a remote mountain environment so we had no internet coverage and strong wireless electromagnetic interference caused by many electronic devices. The shooting site had a large area with many trenches, brick houses, rocks, and steel barriers, so it was difficult to build a WIFI LAN.

The DIT department adopted an enterprise-grade 5G WIFI kilometer coverage solution, with multiple AP devices in each group with ultra-high gain antennas to adjust the coverage at any time according to the progress of the shooting site. The QTake monitor’s stability was enhanced, and the data information collection and management of QTake data at the shooting site was completed more conveniently. In locations with an internet connection, we also provided QTake Cloud Monitor and secure transmission of material in the cloud. The director could monitor the camera feeds of all shooting locations in real-time and instantly upload the QTake recorded proxy footage from all other locations to the cloud space for downloading live clips.

When you think back to the discussed projects, what is your most memorable experience? What did you enjoy the most?

After the shoot wrapped, there were several make-up shoots, one in July was my favorite. In the summer heat, the black cloth covered the tank and I temporarily acted as a stand-in lying under the steel giant in the military uniform. The sense of oppression made me feel the human instinct to retreat, as if I were in the battle, surrounded by gunfire. It really felt as if I had traveled back to that time period.

Another thing I did during the shoot, is that I often created different looks to compare the materials with those from the editing continuity. Eventually, I’d compare the looks with the public screening version and watch the final graded looks to learn from the great colorists, which is something I really enjoy.

Is there anything we haven’t covered, that you would like to share?

Because of the amount of footage we had to shoot, a large number of crew members, and the time it took to film The Battle at Lake Changjin, we had to set up an internal data center server. There, we collected shot and scene information, consolidated the daily agent material of each crew, uploaded daily DIT reports, clip metadata, scene notes, and continuous scene sheets, etc., then generated screenshots and automatic statistics.

The server could sort the scenes according to different directors and groups, produce reports for the staff of each unit, help ensure the continuity of the film shooting, and generate EDL and copy scripts for editing. In addition, The Battle at Lake Changjin has a large number of VFX shots, and the data center helped us maintain the necessary metadata relevant for the post-production.

In the past, production companies ended up only retaining the finished film master. The management and use of project material assets were rarely preserved. D-Plus has built a comprehensive material asset data management process pipeline, relying on the QTake server to build a set of fully customized QTake databases, which best suit a domestic production environment.

We use this to collect and manage the metadata for each clip recorded on the film set so that production companies can view and retrieve data during and after the shoot. This further improves copyright utilization, as well as the subsequent material management of the film and TV clips. At the same time, Silverstack XT adds and manages audio and video-related metadata, and distributes various customized D-Plus DIT reports to multi-departmental staff and creators according to the needs of each department for viewing, communication, and retrieval.

Thank you very much!