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In the last few years the film industry has changed, and nearly every element of the filmmaking process has made wondrous advances. Especially camera equipment. There are so many new digital cinematography tools available to us right now, with different sensor sizes, light sensitivities, resolutions, and capabilities. In this article, I will discuss how all of this presented me with a unique problem, how to directly compare lenses made for different formats. Luckily, there is also a unique solution.
I am working on shooting a film thats in the development phase. This past winter, my director, and I discussed the creative possibilities of shooting the whole film on a single focal length. It’s a creative choice that would lend itself to the story. Seems simple enough, as the name of this post implies, Alfred Hitchcock famously shot Psycho with only a 50mm Spherical lens. I figured why not the classic 50mm. It’s a great focal length for this purpose, not so tight that backing up for a wide is impossible and is pretty flattering to talent in a closeup. I didn’t think too much of it at first. Pick up your favorite 50mm and be done with it. That feeling changed as soon as I started thinking about which camera system to shoot on. I was initially just going to shoot a quick little test with my three favorite 50mm lenses; Cooke S4 T2.0, Bausch & Lomb Super Baltar T2.3 and the Zeiss Super Speed MKII / III T1.3. A quick “Hitchcock Experiment”.
Then something struck me. The cameras we shoot on today, aren’t necessarily S35 sensor size anymore. As I type this, there are commercially available Digital Cinema cameras that have sensors that range from: s8mm, S16mm, S35mm, “Stills” Full Frame and the new frontier of Digital Medium Format. This changes things with regard to what a “50mm” is. When we are talking Super35, the 50mm is the next common tighter lens from a “normal” 35mm. However, when using a stills full frame Digital Cinema camera, 50mm is now the normal focal length. Step up to an even bigger sensor like Digital Medium format, and a 50mm falls on the slightly wider than normal end of the spectrum. What I needed to be testing was field of view, not necessarily the actual focal length. That is roughly 47 degrees field of view. Thats what a 50mm on Super35 sees.
Having to contend with multiple formats did complicate the matter a bit, but it also offered an interesting opportunity. Now that I’m not necessarily limited to S35 anymore, What about my other favorite lenses? Specifically full frame, and Medium format options. I shoot stills on a FUJIFILM GFX100s. It’s a Digital Medium Format mirrorless stills camera, that has a very large 44x33mm Sensor. Full Frame is 36mm x 24mm, and the 16:9 extraction for video is about 36mm x18mm. The GFX100s sensor is using about 44mm x 25mm in 16:9 video mode, though thats its only option for sensor area in video. I have two definite favorite lenses for the GFX100s that are in that 47 degree FOV range. The Pentax 645 75mm F2.8, a beautiful vintage lens from the 1980’s and the FUJIFILM 80mm F1.7, modern, crisp and sharp. I figured I should test all my favorite lenses, of each format, in their native intended format, but choosing the focal length that gives me as close as possible that 47 degrees. My plan was somewhat thwarted, when I realized I’d have to change camera bodies for each group. Comparing lenses directly to each other, but with footage originating from different cameras is not going to give me quite the clean comparison I was looking for. The different cameras will impart their look on the test subject, and skew the results.
(***Very important note here…. Most cinema camera manufacturers have their own sense of what these formats should be sensor dimension wise. For example, the “S35” of a RED Helium, is a different size than that of the Alexa35, which is different than the Alexa XT, which is different than the Alexa Classic, which is different from the Canon C300, the Varicam, the F55, and so on. They are all roughly close to each other, but also in general much bigger than the 16:9 shaped 3 perf film gate… So while the target field of view (FOV) is 47 degrees… The lenses in the test will never truly produce that exact FOV. Variations in the lenses themselves, the target formats, and whether the lenses are even available in the specific focal lengths necessary to make an exact 47degree FOV, meant I had to accept a little leeway. I decided instead to try to find the lenses that matched FOV between the formats that was still reasonably close to the look of a classic 50mm on S35***)
I went to NAB this past spring, and was discussing my challenges with the camera prep on this film with my friends at the FUJIFILM booth. “I just wish the GFX could shoot all the smaller video formats natively, then I could test all the lenses on one camera” I said. They smiled and asked me to contact them in a week when NAB was over. NDA signing later, I was eventually introduced to the GFX100 II. Whats different about this update to the GFX line, is that FUJIFILM really put a lot of thought and care into the Digital Cinema side of the camera. It’s similar in spirit to the latest small mirrorless from FUJIFILM, the X-H2S. The new features are things like high frame rates, 10 bit 4:2:2 4K and 8K ProRes recording on board, 4K 60P, improved dynamic range and an even better Flog2 gamma just to start. The GFX100s, the model I have, was really only able to do up to 30fps in 4k in a AVC intra style H265 codec in 10 bit 4:20 color. While its footage is still great, you are limited to the full size of the sensor and 29.97 fps as a max frame rate in 4K. What really stood out to me was that the GFX100 II, can shoot multi format. You can choose to shoot in full “GF” (Medium format), “PREMISTA” (Full frame), and a “Super35” crop on the sensor. Medium format…. Full Frame…. S35… on one sensor. This was the tool I needed to be able to try out my “Hitchcock Experiment” and get “The Permit” in the can. Now it gets interesting.
Ok, so now that its possible to do this test with results I can actually compare directly, what exactly am I doing?
What I didn’t want to do was a dull lens test. I wanted a scene, not a lens chart. So I came up with a concept paying some homage to “The Conversation”, Francis Ford Coppola’s classic. My writer friend Joseph Piscopo penned a script that accomplished what I needed technically and with great entertainment value. The look of this test, is very similar to the intended look of the feature project, so its a good way to see what lens will be a good match for the mood of the film. What you are going to see is a short film, broken up by “days” in the story. It’s designed to be repetitive in nature, so that we could shoot each day with a different lens and its accompanying format. The shot consists of a tracking stedicam shot, as the main character shows up to work each day, taking a long walk through a factory. The actors movements and the movements of the camera are as consistent as we could possibly make them. There are a few key moments to look out for, detailed after the test film below.
These are the lenses in order of display in the film. All were shot at T2.8 (T2.9 for PREMISTA zoom).
***In the film, Lens #9, the control, shows up first and last to book end the test with a very ubiquitous known quantity, the Alexa Mini, and a popular lens I use often, that I feel is very neutral, the PREMISTA 28-100 zoom. Just to give a sense of what a familiar camera will look like in the scene.***
My goal, is to see which of these lenses, in their native formats, S35, FF and Medium Format, captures the mood of the scene the best. This is the most subjective test I can think of, and thats the point. There is no winner. They are all amazing lenses. I use them all regularly. The goal is not to see what lens is “best” technically… The goal is to see which lens/format is “right” for the storytelling. What makes this test unique, is that for the first time, I can compare not only the characteristics of the lenses, but how they behave in their intended format and how the format also changes the perception of the mood and feel of the film. Bear in mind, this is also all coming from the same camera. The exact same D/R, color science, and light response. The GFX100II is the currently the only cinema camera on the market that can shoot three different motion picture formats, all in 4K-8K. This gives the cinematographer access to not only 120 years of Cine glass, but all the Full Frame, and Medium Format lenses of the past, in their intended formats ( or at least close to it), can now be used to their fullest.
NOTES BEFORE WATCHING:
-The room metered at a T5.6 @800. I used a Formatt Hitech Firecrest .6 ND filter to maintain a T2.8 across all the lenses, as thats my preferred shooting stop. The filter does of course create some reflections under certain circumstances. The most visible one is in the doorway near the red “Exit Sign”. The over head lighting in the background makes a small reflection that gets kicked back to the sensor. This was not visible without the filter in place. It is not indicative of the performance of the GFX100 II
-I opted to try autofocus with the FUJIFILM 80mm F1.7 lens on “DAY 2”. As its a stills lens, and the GFX100II was in beta firmware, I wasn’t able to use its repeatable manual focus function. I didn’t want to mis represent its capabilities before its finished. Essentially, it makes the AF lens behave like a manual lens with repeatable focus movements on the electronic focus ring, allowing for the use of wireless follow focus units. But, it was a cool chance to test out the GFX100 II’s face tracking ability in video. I think it did very well, it remained locked on the subject the entire shot, only hunting when pointing at the surveillance station for a moment.
-You will see a single edit jump cut in Day One / Lens 1 PENTAX 75mm F2.8. This was for audio purposes, as there was interference in one of the takes over his dialogue, and there was a lighting issue on the tail end of the cleanest audio take, when he reaches the surveillance table. I did not want to crop in to help seam the shots together.
-Both cameras, GFX100 II and the Alexa Mini were rated at ISO800.
Without further delay, Please enjoy “The Permit”
You can download the original file from the Vimeo link. Its in 4K ProRes if you would like to see it in its full quality.
THE STATIONS: Some things to keep an eye on.
1 – The Roll Gate. The scene opens with the roll gate. The exterior is 8-9 stops over key as compared to the ambient interior. What I was looking for here is how does a large broad, over exposed element effect the characteristics of the lens. How did they handle this extreme lighting situation? Does the artifacting take you out of it the story. Does it look “weird”…. All things to look out for.
2 – The entrance. As the character continues, we enter into the big room. There is a small light above the talent right at the first turn designed to ping the lens from a high angle. Does it register at all?
3 – The factory floor. As the character continues in the big room. This is one of the longest vistas in the interior. The parallel lights and distant background give a good sense of the bokeh, and how the location reads in relation to the character. Is the background too out of focus to read well etc… This section is available light. Sunlight filtering through sky lights. I was looking for loss of contrast, and any artifacts from having many smaller light sources in the frame.
4 – The doorway. The next turn is designed to mimic a neon, or LED exit sign. I was looking to see if there was any color veiling from having a ton of red light in the frame. This was more specific to the older lenses. Super Baltar, Super Speed and Pentax.
5 – The Long Walk. This section has a row of three fresnels rigged out of frame, providing three levels of backlight. The first just hitting the talent, flagged from camera. The second tilted up slighlty to hit the talent and the camera with an additional unit hitting the lens more aggressively to create a flare. The third, hitting just the talent, but with a 2nd unit hitting just the camera sepreatly. I wanted to see how off of frame flares are handled, as well as how the background separation is in a wider frame.
6 – The surveillance table. Here there is some mixed light. A tungsten lamp illuminating the table, and a daylight backlight. This is the darkest part of the scene, its also when the camera gets the closest. I was looking for how the focus fall off, bokeh, contrast, black level and formats effected the scene.
WORKING WITH THE GFX100II:
It is always fun to try out new cameras. In this case, I was VERY VERY impressed. The GFX100II is stellar. Not just how it looked, but how it worked. It felt like I was using a proper cine camera. The controls were simple and straight forward. Its built “tough”. Featuring a full sized HDMI connection, a strong and snug lens mount with no play and a removable EVF. The removable EVF is great because it lowers the profile of the camera and left more room for accessories. We had no overheating issues but still attached an aftermarket cooling fan for extra protection, but I didn’t think it was needed. The battery life was very good, better than my current GFX100s. I shot a combination of Prores 4K and 8K. The super35 modes to get the proper S35 frame size, you have to record in 8K. Its basically “pixel for pixel” readout.
I used a Fotodiox Pro – PL to GFX lens mount adapter. The same adapter I use on my GFX100s. A testament to the quality FUJIFILM puts into their cameras, the mount was spot on collimated on both of the bodies. You could use the lens marks with a measuring tape. With other mirrorless cameras I’ve owned, shimming a PL mount for one body didn’t mean it would be correctly collimated for another body in the same line. It bodes well that both were just about perfect.
We also used a Kondor Blue prototype cage to mount accessories and rails. The camera was powered by from a battery plate that also powered the Teradek Bolt 6 – XT with panel array on the receiver. I reached out to my friends at CSLA , Teradek and SmallHD, and asked if they could help out with this project. I needed to use the most powerful wireless system they had. I knew the walls of this factory were going to be a problem. Graciously they let me borrow the best of what they make. Amazingly, the Bolt 6 was able to reach the video village consisting of a Small HD 24″ OLED monitor, with a crystal clear signal through thick brick walls and at times over 150 feet of distance with zero line of sight. It was a life saver. We also used a Teradek RT wireless Follow focus, and 1st AC Ryan Patrick O’hara mapped all of the lenses, so that each individual lens would have the same focus throw on the hand unit. This way as we rehearsed the move, regardless of the lens, it would feel the same to him. He is living autofocus that never misses. It’s remarkable.
Considering the length of the takes, and precision of the move, our Stedicam operator Jason Leeds, SOC, certainly appreciated the light weight of the build. I capped us at 3 takes per day/lens in the script. It worked out to about 30 takes in all… each over two minutes counting frame up and slate. Thats a long time to be framed and moving with precision. Jason is an amazing operator.
Now… the part I love…. The image…. I recorded in Flog2, FUJIFILM’s new log gamma. It’s flatter than the previous version and it needs it to store all the image data. The GFX100 II has excellent dynamic range and color. I didn’t put it on a XYLA chart, but it felt close to the Alexa Mini in over all dynamic range. The Mini had a stop or so more highlight latitude. The GFX100 II was MUCH cleaner in the shadows than the Alexa. I would comfortably shoot it as high as 3200 ISO. As you saw, in a real world filmmaking scenario, the GFX100 II held its own against the gold standard in the industry, the Alexa Mini. I would even be bold enough to say I preferred the color science in the GFX100 II. It always locked in on the skin tones easily in the color suite, and it represented the other colors in the scene very accurately. Even the Mini sometimes shifts aquas and teals to green or blue. The GFX100 II was dead on with colors, from everything from skin, to wardrobe, to the elements in the location.
The ProRes footage is very easy to cut. While the GFX100II can do 12bit 4K RAW over HDMI to a recorder, I opted to shoot ProRes as I felt thats what most users will shoot. It graded and edited like butter on a M1 mac. Even the 8K footage.
To maintain consistency, I used FUJIFILM’s Flog2 to Eterna LUT. I metered the factory location with a Sekonic C800 Color meter, and found an ambient color temperature of 5100K. The Cameras were set to 5100K and not rebalanced for the rest of the shoot. The factory lighting was consistent, and we shot so quickly that the sun did not have a very drastic shift. Any color shifting you see between the days is imparted by the lens. The Control footage from the Alexa I did however grade a little bit using Film Convert’s Fuji Film looks as a starting point. It tracked surprisingly well.
I realized something thats actually kind of cool. Since you can have three different format based DOF characteristics, You can in theory carry three “47Degree FOV” lenses, and choose between them for the kind of DOF and background separation you need in a particular shot, while not changing the “rules” of maintaining the same field of view. Think if it as changing lenses, without changing lenses.
It was important to me to really give this test a finished look. There is no more real world trial for a lens than actually shooting something with it in the field. With the support of some amazing people we pulled together and made what I hope was entertaining as much as it was informative.
I wanted to create a world, and see how the lenses reacted to the world. Our production designer Abigail Stanton worked tirelessly and really made the place feel lived in and real. Not only did the film have a sense of time and place, but small details like finger prints and crumbs on the table really pulled it all together.
Josh Benson our gaffer, spent the better part of a day carefully blocking skylights and windows, then re lighting big sections of the walking segment to maintain the look and feel of the space. We had very limited tools, but the G/E team made the most of what we did have. We had only a handful of my own personal Rayzr lighting: three Rayzr 7 fresnels, 1x 2×1 Rayzr MC400 max panel, 4 LED tubes, and 2 Rayzr Mono lights. Josh somehow lit 100,000 square feet with only that, a few Cardelini clamps and a couple rolls of duvateyne. Brilliant gaffer.
I know what my favorite lens is out of the bunch. Whats yours? That’s the point of this. It is purely subjective.
I found this project very personally informative. It was an interesting experience, seeing how certain lenses brought the scene to life. Their characteristics just happened to mesh with the content…. to me…. I would be willing to bet that different people have differing opinions of which lens that actually is.
I was excited that the stars aligned so that I could actually perform this test. This would not have happened without the generous support from FUJIFILM, not only supplying me with a beta camera that was physically able to make this all possible, but supporting the production and bringing me the fabulous production team at Pairadox Studios: Jackie Merry, Casper Hanney, Nhung Nguyen and Tani Shukla. Without their support this would have been impossible.
Thank you for reading, I hope you enjoyed it as much as I did making it.