If you’ve done much still photography, particularly on celluloid, you will probably have heard of the Sunny 16 Rule. It’s a useful shortcut for correctly exposing bright day exteriors without needing a light meter. Is it of any use in digital cinematography though? Yes, and I’ll explain how.
How the rule Works
Sunny 16 is very simple: if the sun is out, set your aperture to f/16 and your shutter speed denominator to the same as your ISO. For example, at ISO 100 set the shutter to 1/100th of a second. At ISO 400 set the shutter to 1/400th of a second – or 1/500th of a second, if that’s the closest option the camera permits – and so on.
You can use the rule to work out other combinations from there. Say your ISO is 100 but you want the sharper, less motion-blurred look of a 1/400th shutter. That’s two stops slower, so open the aperture from f/16 to f/8. (Check out my exposure series if this is all Dutch to you.)
The Sunny 16 Rule works because the sun outputs a constant amount of light and is a constant distance from the earth – at least constant enough to make no significant difference. The sun’s illuminance at the earth’s surface is about 10,000 foot-candles. The following formula relates illuminance (b) to f-stop (f), shutter speed (s) and ISO (i):
Using Sunny 16 in the case of ISO 100 and a shutter speed of 1/100th of a second, this formula gives us…
… 6,400 foot-candles. Less than 10,000fc, certainly, but remember this is only a rule of thumb – and one designed for film, which isn’t hurt at all by a little over-exposure. The rule probably accounts for the fact that you may want to see into the shadows a bit too. (See my article “How Big a Light Do I Need?” for explanations of illuminance and foot-candles and more on the above formula.)
Anyway, you can see from the equation why the shutter speed denominator and ISO cancel each other out if they’re the same.
Using the rule in cinematography
A few weeks ago when I was on the banks of the River Cam setting up for a scene in Harvey Greenfield is Running Late, my 1st AC Hamish Nichols asked which ND filter I wanted in the matte box. It was 5:30am; the sun had barely risen and certainly wasn’t high enough yet to reach me and my light meter over the trees and buildings on the horizon. But I knew that it would be hitting us by the time we turned over, and that the weather forecast was for a completely cloudless day, indeed the hottest day of the year at that time. So I was able to predict that we’d need the 2.1 ND.
How did I work this out? From the Sunny 16 Rule as follows:
I was shooting with a 1/50th of a second shutter interval (a 172.8° shutter angle at 24fps), so the Rule told me that f/16 (or T16) at ISO 50 would be the right exposure.
I was actually at ISO 800, which is four stops faster than ISO 50. (Doubling 50 four times gives you 800.)
I wanted to shoot at T5.6, which is three stops faster than T16.
That’s a total of seven stops too much light. To find the right optical density of ND filter you multiply that by 0.3, so 0.3 x 7 = 2.1. (More on this in my ND filters post.)
Everything on a film set sucks up time, so the more you know in advance, the more efficient you can be. Little tricks like this mean you don’t have to do a last-minute filter swing and waste five minutes that the director could have used for another take.
In last week’s post I mentioned the minor trouble we had on Harvey Greenfield is Running Late with a flickering TV screen in the background of shot. In today’s post I’m going to look at the underlying maths, find out why the 144° shutter angle I ultimately chose gave the best results and how to calculate the exposure compensation when you change your shutter angle like this.
If you haven’t already read my exposure series, particularly the posts about shutter and ISO, I suggest you look at those before diving into this one.
Working out the shutter interval
Harvey Greenfield was shot at 24fps here in the UK, where the mains current alternates at 50Hz (i.e. 50 cycles per second). To avoid certain light sources and any screens in shot from flickering, you generally want to match your shutter interval – the period of time during which light is allowed to charge the sensor’s photosites – to the AC frequency, i.e. 1/50th of a second in the UK. That works out to a shutter angle of 172.8° because…
frame rate x shutter interval x 360 = shutter angle
24 x (1 ÷ 50) x 360 = 172.8
So, as with all features I shoot in the UK, I captured most of Harvey at a shutter angle of 172.8°.
Going back to the TV problem, I scrolled through the Red Gemini’s available shutter angles until I found the one that gave the least flicker: 144°. With the twin wonders of hindsight and maths I can work out what frequency the TV was operating at, using the first version of the formula above.
24 x (360 ÷ 144) = 60
144° with a frame rate of 24 meant that the Red was capturing 1/60th of a second’s worth of light each frame. To produce (almost) no flickering at this camera setting, the TV was evidently operating at 60Hz.
Working out the exposure compensation
Reducing your shutter angle reduces the amount of light captured by the sensor each frame, i.e. it reduces the exposure. I was happy with the depth of field and didn’t want to change the aperture, so instead I compensated by increasing the ISO from 800 to 1280. This was a guess made under time pressure on set, but now I can calculate the right exposure compensation at my leisure.
Fortunately, unlike f-stops, shutter angles and ISO are linear scales. Double the shutter angle or ISO and you double the exposure; halve the shutter angle or ISO and you halve the exposure. This makes the maths relatively easy.
172.8° was my original shutter angle. Let’s think of this as 100% exposure. When I went down to 144°, what percentage of the original exposure was that? I still remember the mantra from calculating maths workbook scores in secondary school: “What you got divided by what you could have got, times 100.”
(144 ÷ 172.8) x 100 = 83%
Now we turn to the ISO. At its original value, 800, the camera is only providing 83% of the desired exposure, thanks to the reduced shutter angle. What must we increase the ISO to in order to hit 100% again?
(800 ÷ ?) x 100 = 83%
800 ÷ ? = 0.83
800 ÷ 0.83 = ? = 960
So I should have been at ISO 960 ideally. The closest available setting on the Red is ISO 1000, not 1280 as I selected, so I was actually over-exposing by a third of a stop. Given that we were shooting in RAW, so the ISO is only metadata, and I could see from the false colours display that nothing was clipping, this is a very minor error indeed.
Letting the meter do the maths
One more thing. My Sekonic L-758D light meter assumes a 180° shutter (so I set it to 25fps when I’m actually shooting 24fps at 172.8°, as both work out to 1/50th of a second). Another way I could have worked the correct exposure out, if I’d clocked the 60Hz frequency of the TV at the time, is to have set the meter to 30fps (1/60th of a second at 180°) and then changed the ISO until it gave me the stop I wanted.
I think the director is turning into Harvey Greenfield. This morning Jonnie burst unexpectedly out of a hedge apologising for being slightly late.
Our first location was a surprisingly busy park in the village of Exning. We shot under the trees lining the edge of the park, keeping the camera on the same side of the eye-line as this handy arboreal negative fill, allowing the open sky of the park proper to light the actors’ off-camera sides. It’s great when blocking works out in your favour like this.
Then we moved around the corner to Wests Garage. First up here was a 24mm tableau shot to establish Barry the mechanic when he first calls Harvey, just as we have done to introduce the other supporting characters. We placed Barry in an office with a window behind him showing the workshop. Stephen arranged our four Astera tubes (in tungsten mode) around the workshop as practical work-lights, clamping some to pillars and placing others on the floor; wherever possible we are adding orange splashes of light (Harvey’s stress colour) into the background of these tableaux.
Next we shot outside around a car (a Rover I think – they all look the same to me), getting a nice slider shot parallel to the vehicle. Shades of Wes Anderson again. The trouble with all these straight-on shots of windows and shiny cars is hiding all the reflections. Stephen had to build a wall of floppy flags to disguise the slider.
By the time we wrapped the heat was getting to us all, and there was nothing for it but to try out the local pub.
But that was closed for a private party so we went to the other local pub instead.
Jonnie was wearing Harvey’s jacket. Definitely turning into him.
We were at Othersyde, part of the Cambridge Museum of Technology, for the biggest day of the shoot: 12 scenes and nine pages of script to cover.
We began in a tent – Amanda had kindly found an orange one at my request – which we flagged on one side, adding the Aputure 300D to the other side to bring some shape to the lighting.
Then we moved into one of the venue’s toilet cubicles, where we simply added a skirt of black wrap to the existing overhead light fitting to reduce the light on the walls and add contrast. (Stephen and spark daily James also had to build a black-out tent around the door so that it could be open for the camera to see in without admitting daylight.)
Then we jumped into the bar of the Engineer’s House to grab a one-shot flashback scene. We lit through two windows (the Aputure and the Litemat 2S, I think) and added fill (a CTB-gelled 2K bounced off poly) and a couple of other sources inside (an Aladdin into a dark corner; a tungsten lamp shining down some background stairs). The shot required some well-timed whip-pans – always good for comedy. These require great skill as a camera operator when executed on sticks, but fortunately for me this one was handheld which makes the muscle-memory involved much easier.
Next we were in another toilet cubicle. Again we skirted the ceiling light and tented around the door, but this time another character had to come in. Here we used an LED fixture which Stephen built himself, gelling it with Urban Sodium as this shot is part of a sequence that has a stressy, streetlamp look to it.
By this time it was getting towards evening and we set up for a slider shot at the front of the site, overlooking the River Cam and shooting towards the low sun. Thanks to Helios Pro – a sun tracking app – we managed to time this just right. A 4×4 poly bounce either side of camera was all that was needed to supplement the beautiful natural light.
Sounds like all that would be enough for one day, doesn’t it? But oh no, the big scene was still to come. With 20 or 30 extras we staged a wedding reception under Othersyde’s marquee. Stephen keyed the wedding party at the head table with the Aputure bounced off poly (both rigged to the marquee’s ceiling) and we backlit them with a tungsten 1K firing out of an upper window of the Engineer’s House. A character off to one side was lit with an Aladdin rigged to the roof of the bar. The aim was to keep the lighting fairly warm overall, but to make those warm foreground colours pop we added blue-gelled 300W fresnels uplighting the Engineer’s House and a 1K in the deep background, gelled with Steel Blue, for a hint of moonlight. All of this was supplemented by the venue’s existing string lights, bar lights, LED uplighters in the flower beds and candles which Amanda placed on the tables.
Although we didn’t quite make the call sheet, we only dropped one brief scene – a pretty amazing result and one for the whole team to be proud of. Our welcome reward was a selection of Othersyde’s finest pizzas.
The morning was spent with a beautiful horse-drawn hearse (featuring more fun reflective surfaces!) while the afternoon took place around an off-camera grave in Ely Cemetery. Some brief scenes with the child actors, faking a corner of the cemetery as a park, completed a damp but straightforward day for cinematography.
About a third of Harvey Greenfield is Running Late takes its title very literally, seeing Paul Richards’ character hurrying to his next appointments as he makes phone calls and talks to camera. Today was the first day dedicated to capturing these scenes.
The first few scenes were shot as Annie Hall-esque wides in the streets and parkland around of Ely. (Much as Hot Fuzz filmed in Wells but painted out the cathedral, we framed out Ely Cathedral to avoid it becoming an identifiable landmark.)
To get a shot of Harvey looking down at a piece of litter, we put the empty beer can on top of two peli cases. Using the lovely wide 14mm lens we were then able to shoot up past it to Harvey and even rack focus to the can. I never usually hire anything wider than an 18mm but I have certainly learnt to appreciate what a 14mm can do on this shoot, even if it does make lighting and boom-operating more challenging.
Our Steadicam operator Rupert joined us again for the rest of the day, bringing along a rickshaw to enable him to track Harvey more smoothly. This drew plenty of attention from the general public, particularly when we moved down to Ely’s picturesque riverside. Most people were very friendly and kindly stayed out of frame if asked to, but a couple of self-styled pirates seemed determined to get an unscripted cameo. Nevertheless we managed to pull off a long and complicated shot which begins with Harvey approaching camera down a tree-lined car park and then tracks him in profile as he pelts along the riverbank.
The morning was spent filming outside a house in Romsey – a short walk from home for me – which was standing in for Harvey’s. There was yet more fun with reflections when we had to shoot Harvey’s neighbour looking out of his window. No matter how tight the budget is, I will never ever take a polarising filter off my kit hire list again.
In the afternoon we captured more Steadicam running scenes around Romsey Park, before moving onto the nearby streets when it got dark. Here the Gemini’s low light mode saw use again, allowing us to rely mostly on the existing streetlamps (not pretty, but it works for the story). Stephen rigged an Aladdin to the rickshaw so that Harvey would have a little fill light moving with him.
Finally we moved back into the park, where Stephen had cross-lit the kids’ playground with tungsten sources. This formed the background of the scene, with the action taking place under a streetlamp in front of the play area. As the streetlamp was naturally very toppy, we fired in a Litemat (gelled with Urban Sodium) from above the camera to make sure that we would see Paul’s face for this critical performance scene.
There will be more on Harvey Greenfield‘s second week in my next post. In the meantime you can follow the film’s official Instagram account or Facebook page.
So far in this series we have seen how we can adjust exposure using aperture, which affects depth of field, ND filters, which can help us retain the depth of field we want, and shutter angle, which affects motion blur and flickering of certain light sources. In this final part we’ll look at ISO, perhaps the most misunderstood element of exposure, if indeed we can technically classify it as part of exposure at all!
What is ISO?
The acronym stands for International Organization for Standardization, the body which in 1974 combined the old ASA (American Standards Association) units of film speed with the German DIN standard. That’s why you’ll often hear the terms ISO and ASA used interchangeably.
Two different cameras filming the same scene with the same filters, aperture and shutter settings will not necessarily produce an image of equal brightness, because the ways that their electronics convert light into video signals are different. That is why we need ISO, which defines the relationship between the amount of light reaching the sensor (or film) and the brightness of the resulting image.
For example, a common ISO to shoot at today is 800. One way of defining ISO 800 is that it’s the setting required to correctly expose a key-light of 12 foot-candles with a lens set to T2.8 and a 180° shutter at 24fps (1/48th of a second).
If we double the ISO we double the effective sensitivity of the camera, or halve the amount of light it requires. So at ISO 1600 we would only need 6 foot-candles of light (all the other settings being the same), and at ISO 3200 we would need just 3 foot-candles. Conversely, at ISO 400 we would need about 25 foot-candles, or 50 at ISO 200.
A Flawed Analogy
Note that I said “effective” sensitivity. This is an important point. In the photochemical world, ISO indeed denotes the light sensitivity of the film stock. It is tempting to see digital ISO as representing the sensitivity of the sensor, and changing the ISO as analogous to loading a different film stock. But in reality the sensitivity of a digital sensor is fixed, and the ISO only determines the amount of gain applied to the sensor data before it is processed (which may happen in camera if you’re shooting linear or log, or in post if you’re shooting RAW).
So a better analogy is that altering the ISO is like altering how long the lab develops the exposed film negative for. This alters the film’s exposure index (EI), hence some digital cameras using the term EI in their menus instead of ISO or ASA.
We can take this analogy further. Film manufacturers specify a recommended development time, an arbitrary period designed to produce the optimal image. If you increase (push) or decrease (pull) the development time you will get a lighter or darker image respectively, but the quality of the image will be reduced in various ways. Similarly, digital camera manufacturers specify a native ISO, which is essentially the recommended amount of gain applied to the sensor data to produce what the manufacturer feels is the best image, and if you move away from that native ISO you’ll get a subjectively “lower quality” image.
The most obvious side effect of increasing the ISO is more noticeable noise in the image. It’s exactly the same as turning up the volume on an amplifier; you hear more hiss because the noise floor is being boosted along with the signal itself.
I remember the days of Mini-DV cameras, which instead of ISO had gain; my Canon XL1 had gain settings of -3dB, +6dB and +12dB. It was the exact same thing, just with a different name. What the XL1 called 0dB of gain was what we call the native ISO today.
ISO and Dynamic range
At this point we need to bring in the concept of dynamic range. Let’s take the Arri Alexa as an example. This camera has a dynamic range of 14 stops. At its native ISO of 800, those 14 stops of dynamic range are equally distributed above and below “correct” exposure (known as middle grey), so you can overexpose by up to seven stops, and underexpose by up to seven stops, without losing detail.
If you change the Alexa’s ISO, those limits of under- and overexposure still apply, but they’re shifted around middle grey. For example, at 400 ISO you have eight stops of detail below middle grey, but only six above it. This means that, assuming you adjust your iris, shutter or filters to compensate for the change in ISO, you can trade-off highlight detail for shadow detail, or vice versa.
Imagine underexposing a shot by one stop and bringing it back up in post. You increase the highlight detail, because you’re letting half the light through to the sensor, reducing the risk of clipped whites, but you also increase the noise when you bring it up in post. This is basically what you’re doing when you increase your ISO, except that if you’re recording in linear or log then the restoration of brightness and increase in gain happen within the camera, rather than in post with RAW.
We can summarise all this as follows:
Doubling the ISO…
increases overall brightness by one stop, and
increases picture noise.
Then adjusting the exposure to compensate (e.g. closing the iris one stop)…
restores overall brightness to its original value,
gives you one more stop of detail in the highlights, and
gives you one less stop of detail in the shadows.
Alternatively, halving the ISO…
decreases overall brightness by one stop, and
decreases picture noise.
Then adjusting the exposure to compensate (e.g. opening the iris one stop)…
restores overall brightness to its original value,
gives you one less stop of detail in the highlights, and
gives you one more stop of detail in the shadows.
This brings me to the end of my exposure series. We’ve seen that choosing the “correct” exposure is a balancing act, taking into account not just the intended brightness of the image but also the desired depth of field, bokeh, lens flares, motion blur, flicker prevention, noise and dynamic range. I hope this series has helped you to make the best creative decisions on your next production.
A couple of weeks ago I shared my thoughts about whether a director of photography should own equipment. My conclusion was that it can be useful early in your career, when you’re shooting corporates or tiny films with no hire budget. So what is the best camera for indie cinematography?
I’m not going to answer that, but I will tell you what to look for when investing in a camera. Hopefully these tips will help you choose the one that’s right for you from the huge and ever-changing array of professional cameras on the market, from the humble DSLR to the ubiquitous Reds and everything in between.
1. Image quality
The quality of the image is of course the most imporant attribute of any camera. Rather than any technical specifications, I’m talking about the aesthetic quality here: how does it feel? Does it have that elusive “cinematic” quality? Is it “filmic”? Does it remind you of certain kinds of movies?
A good place to start is to look up sample footage on YouTube, or better still Vimeo for less compression muddying the issue. If you can borrow the camera and try it out before you buy, even better. Take away some test footage and try grading it too.
Resolution, the sheer number of pixels a camera can record, is part of image quality, but I include it as a separate point because I see it as more of a technical consideration than an aesthetic one. You should ask yourself what longevity you require from your films – will people still be watching them, say two or three years from now, and if so what sort of resolution might be the norm by then?
Also consider your delivery platform. If everything you shoot is going on YouTube, perhaps you don’t need more than 1080P (standard HD).
3. Dynamic Range
Dynamic range is a measure of how much contrast a camera can handle. Too small a dynamic range and you will frequently struggle with bright areas “clipping” – i.e. losing details – or dark areas getting lost in the image noise. Also, the wider the dynamic range, the more flexibility you will have in grading.
For a cinematic image, 12 stops of dynamic range is the absolute minimum, with 14 or more being ideal.
4. Maximum ISO
The ISO (International Standards Organisation) scale rates the light sensitivity of a camera. The most important thing is the native ISO, the one at which the camera is optimised to give the cleanest image with the most detail. On some cameras, setting an ISO other than the native one reduces the image quality considerably.
The higher the ISO, the less light will be required to expose an image correctly. 800 is typical these days, but many cameras go much higher than that. It is worth thinking about spending more money to get a camera with a higher native ISO, because you may save a lot of money on lighting.
5. Lens Mount
This is crucial because you may already have a collection of lenses, or you may intend to hire certain lenses, and you need to be sure that they will fit your new camera’s mount.
The Canon EF mount is extremely common and will open up a huge range of options for stills glass as well as some low-end cinema glass. The smaller MFT (micro four-thirds) mount also has a wide range of lenses.
Top-end cameras have PL mounts which take all the beautiful cinema lenses used on big movies, but only choose this route if you are willing to part with a lot of cash!
6. Form Factor
When I started in the industry, cameras were all ergonomically designed to sit on your shoulder, with a nice handgrip to the right of the lens and an EVF (electronic viewfinder) to provide a third point of stabilising contact. Nowadays cameras tend to be boxy, heavy and uncomfortable to hold without additional accessories (see below).
Again, try to gets your hands on the camera in a shop and see how it feels before you purchase. As well as handheld shooting, consider how easy it will be to rig onto dollies, sliders, gimbals, etc.
7. Required Accessories
Buying the camera body itself is unlikely to be the end of your expenditure. You will need lenses, batteries, a battery charger, cards, a card reader and almost certainly some kind of stabilising system, be it a simple shoulder rig or an electronic gimbal.
You may also want an EVF, a tripod, matte box, follow focus – the list can seem endless! Be careful to budget your essential accessories before buying the camera. Some cameras seem like bargains until you add up all the extras. Pay particular attention to the media, and to exactly what speed of media you need in order to shoot at the resolution and frame rate that you require, as this can get very expensive.
What file type and codec does the camera shoot? Does your editing system support that format? If not, how time-consuming will it be to convert everything?
What compression ratios does the camera support? How much hard drive space will you need to store an hour of footage at that ratio? What about ten hours, plus back-ups? Often there is a trade-off between a highly compressed format like H.264 which is light on disc space but may need converting before you can edit it, and a lightly compressed format like ProRes which burns through disc space but can be dropped straight into most editing software.
Two years ago I made Stasis, a series of photographs that explored the confluence of time, space and light. Ever since then I’ve been meaning to follow it up with another photography project along similar lines, but haven’t got around to it. Well, with Covid-19 there’s not much excuse for not getting around to things any more.
So I’ve decided to make a zoetrope – a Victorian optical device which produces animation inside a spinning drum. The user looks through slits in the side of the drum to one of a series of images around the inside. When the drum is set spinning – usually by hand – the images appear to become one single moving picture. The slits passing rapidly through the user’s vision serve the same purpose as a shutter in a film projector, intermittently blanking out the image so that the persistence of vision effect kicks in.
Typically zoetropes contain drawn images, but they have been known to contain photographed images too. Eadward Muybridge, the father of cinema, reanimated some of his groundbreaking image series using zoetropes (though he favoured his proprietary zoopraxiscope) in the late nineteenth century. The device is thus rich with history and a direct antecedent of all movie projectors and the myriad devices capable of displaying moving images today.
This history, its relevance to my profession, and the looping nature of the animation all struck a chord with me. Stasis was to some extent about history repeating, so a zoetrope project seemed like it would sit well alongside it. Here though, history would repeat on a very small scale. Such a time loop, in which nothing can ever progress, feels very relevant under Covid-19 lockdown!
With that in mind, I decided that the first sequence I would shoot for the zoetrope would be a time-lapse of the cherry tree outside my window. I chose a camera position at the opposite end of the garden, looking back at my window and front door – my lockdown “prison” – through the branches of the tree. (The tree was just about to start blooming.)
The plan is to shoot one exposure every day for at least the next 18 days, maybe more if necessary to capture the full life of the blossom. Ideally I want to record the blossom falling so that my sequence will loop neatly, although the emergence of leaves may interfere with that.
To make the whole thing a little more fun and primitive, I decided to shoot using the pinhole I made a couple of years ago. Since I plan to mount contact prints inside the zoetrope rather than enlargements, that’ll mean I’ve created and exhibited a motion picture without ever once putting the image through a lens.
I’m shooting on Ilford HP5+, a black-and-white stock with a published ISO of 400. My girlfriend bought me five roles for Christmas, which means I can potentially make ten 18-frame zoetrope inserts. I won’t be able to develop or print any of them until the lockdown ends, but that’s okay.
My first image was shot last Wednesday, a sunny day. The Sunny 16 rule tells me that at f/16 on a sunny day, my exposure should be equal to my ISO, i.e. 1/400th of a second for ISO 400. My pinhole has an aperture of f/365, which I calculated when I made it, so it’s about nine stops slower than f/16. Therefore I need to multiply that 1/400th of a second exposure time by two to the power of nine, which is 1.28 – call it one second for simplicity. ( I used my Sekonic incidence/reflectance meter to check the exposure, because it’s always wise to be sure when you haven’t got the fall-back of a digital monitor.)
One second is the longest exposure my Pentax P30t can shoot without switching to Bulb mode and timing it manually. It’s also about the longest exposure that HP5+ can do without the dreaded reciprocity failure kicking in. So all round, one second was a good exposure time to aim for.
The camera is facing roughly south, meaning that the tree is backlit and the wall of the house (which fills the background) is in shadow. This should make the tree stand out nicely. Every day may not be as sunny as today, so the light will inevitably change from frame to frame of the animation. I figured that maintaining a consistent exposure on the background wall would make the changes less jarring than trying to keep the tree’s exposure consistent.
I’ve been taking spot readings every day, and keeping the wall three-and-a-half stops under key, while the blossoms are about one stop over. I may well push the film – i.e. give it extra development time – if I end up with a lot of cloudy days where the blossoms are under key, but so far I’ve managed to catch the sun every time.
All this exposure stuff is great practice for the day when I finally get to shoot real motion picture film, should that day ever come, and it’s pretty useful for digital cinematography too.
Meanwhile, I’ve also made a rough prototype of the zoetrope itself, but more on that in a future post. Watch this space.
Last autumn, after a few years away from it, I got back into 35mm stills photography. I’ve been reading a lot of books about photography: the art of it, the science and the history too. I’ve even taken a darkroom course to learn how to process and print my own black and white photos.
Shooting stills in my spare time gives me more opportunities to develop my eye for composition, my exposure-judging skills and my appreciation of natural light. Beyond that, I’ve discovered interesting parallels between electronic and photochemical imaging which enhance my understanding of both.
For example, I used to think of changing the ISO on a digital camera as analogous to loading a different film stock into a traditional camera. However, I’ve come to realise it’s more like changing the development time – it’s an after-the-fact adjustment to an already-captured (latent) image. There’s more detail on this analogy in my ISO article at Red Shark News.
The importance of rating an entire roll of film at the same exposure index, as it must all be developed for the same length of time, also has resonance in the digital world. Maintaining a consistency of exposure (or the same LUT) throughout a scene or sequence is important in digital filmmaking because it makes the dailies more watchable and reduces the amount of micro-correction which the colourist has to do down the line.
Anyway, this is all a roundabout way of explaining why I decided to make a pinhole attachment for my SLR this week. It’s partly curiosity, partly to increase my understanding of image-making from first principles.
The pinhole camera is the simplest image-making device possible. Because light rays travel in straight lines, when they pass through a very small hole they emerge from the opposite side in exactly the same arrangement, only upside-down, and thus form an image on a flat surface on the other side. Make that flat surface a sheet of film or a digital sensor and you can capture this image.
How to make a pinhole attachment
I used Experimental Filmmaking: Break the Machine by Kathryn Ramey as my guide, but it’s really pretty straightforward.
You will need:
an extra body cap for your camera,
a small piece of smooth, non-crumpled black wrap, or kitchen foil painted black,
gaffer tape (of course), and
a needle or pin.
Drill a hole in the centre of the body cap. The size of the hole is unimportant.
Use the pin or needle to pierce a hole in the black wrap, at least a couple of centimetres from the edge.
Cut out a rough circle of the black wrap, with the pinhole in the middle. This circle needs to fit on the inside of the body cap, with the pinhole in the centre of the drilled hole.
Use the gaffer tape to fix the black wrap tightly to the inside of the body cap.
Fit the body cap to your camera.
The smaller the pinhole is, the sharper the image will be, but the darker too. The first pinhole I made was about 0.1-0.2mm in diameter, but when I fitted it to my camera and looked through the viewfinder I could hardly make anything out at all. So I made a second one, this time pushing the pin properly through the black wrap, rather than just pricking it with the tip. (Minds out of the gutter, please.) The new hole was about 0.7mm but still produced an incredibly dark image in the viewfinder.
Exposing a pinhole image
If you’re using a digital camera, you can of course judge your exposure off the live-view screen. Things are a little more complicated if, like me, you’re shooting on film.
In theory the TTL (through the lens) light meter should give me just as reliable a reading as it would with a lens. The problem is that, even with the shutter set to 1 second, and ISO 400 Fujifilm Super X-tra loaded, the meter tells me I’m underexposed. Admittedly the weather has been overcast since I made the pinhole yesterday, so I may get a useful reading when the sun decides to come out again.
Failing that, I can use my handheld incident-light meter to determine the exposure…. once I’ve worked out what the f-stop of my pinhole is.
As I described in my article on aperture settings, the definition of an f-stop is: the ratio of the focal length to the aperture diameter. We’re all used to using lenses that have a clearly defined and marked focal length, but what is the focal length in a pinhole system?
The definition of focal length is the distance between the point where the light rays focus (i.e. converge to a point) and the image plane. So the focal length of a pinhole camera is very simply the distance from the pinhole itself to the film or digital sensor. Since my pinhole is more or less level with the top of the lens mount, the focal length is going to be approximately equal to the camera’s flange focal distance (defined as the distance between the lens mount and the image plane). According to Wikipedia, the flange focal distance for a Pentax K-mount camera is 45.46mm.
So the f-stop of my 0.7mm pinhole is f/64, because 45.64 ÷ 0.7 ≈ 64. Conveniently, f/64 is the highest stop my light meter will handle.
The website Mr Pinhole has a calculator to help you figure this sort of stuff out, and it even tells you the optimal pinhole diameter for your focal length. Apparently this is 0.284mm in my case, so my images are likely to be quite soft.
Anyway, when the sun comes out I’ll take some pictures and let you know how I get on!
This is the second part of my report from my time at Camerimage, the Polish film festival focused on cinematography. Read part one here.
Panavision: The BEauty of 8K Large Format
It was a chilly but bright morning as I strolled into Bydgoszcz and made straight for the MCK Orzeł, where I planned to spend most of the day. With only a few minutes to go until the scheduled start time, the queue for Panavision’s large format seminar had spilt out onto the street. The tickets ran out before I reached the desk, but there was a live video feed in the cinema’s bar. In many ways this was better than going into the auditorium – sitting in a comfy chair with the bar close at hand, and a table to make notes on.
My article for Red Shark News about the future of large format cinematography has been surprisingly popular, and it contains plenty of detail about this Panavision seminar, so I won’t repeated myself here. I will say that it converted me from a high resolution sceptic to a believer, because the speakers demonstrated that footage acquired in high rez – even when downscaled – retain much of its smoothness, high bit depth and dynamic range. “More resolution evokes the imagination of the brain,” was how colourist Ian Vertovec summed it up.
At the end of the session, Red Shark’s David Shapton and Matt Gregory emerged from the auditorium and joined me for lunch at the bar. We had all found the seminar very interesting, and Matt was quick to get us all tickets to the Panasonic 4K seminar coming up later in the day. The pair then went off to other things, while I headed to the kiosk to get a ticket for the imminent John Toll seminar. But of course I’d left it too late, they were all gone, and so I returned to my comfy chair in the bar to watch via video feed again.
Panavision workshops: A conversation with John Toll, ASC
John Toll, ASC was the recipient of this year’s Lifetime Achievement Award at Camerimage, and this seminar was an epic journey through this career. He explained how he learnt his craft as a camera operator for the late great Conrad Hall, ASC and Jordan Cronenweth, ASC.
The talk then focused on some of Toll’s biggest movies, beginning with the period drama Legends of the Fall starring Brad Pitt and Anthony Hopkins. The movie was largely daylight exterior (something that was to become a theme across Toll’s work) so the cinematographer insisted on twelve weeks of prep, the same as the production designer. This allowed him to be part of selecting locations and choosing orientations for the buildings to get the optimal sun path. Toll said he was lucky that the 1st AD was willing to be flexible with the schedule, observing the mood of the weather each day and shooting scenes that matched that mood.
Gaffer Jim Plannette joined Toll on the stage to discuss the huge night exterior battle sequence. This employed three Musco lights (a Musco being fifteen 6K pars on a 100ft boom arm) which three-quarter-backlit every angle. To get crisp, grain-free blacks, Toll overexposed and printed down.
Braveheart was covered next, with 1st AC Graham Hall joining the panel. Hall had a difficult time with the film’s battle scenes, featuring as they did so much movement, improv and slo-mo. Toll revealed how the immersive style of the action was based on a sixties TV documentary about Culloden that coincidentally both he and director Mel Gibson had seen. A lot of colour timing was required to give consistency to the battles, which were shot over weeks, at all times of day.
The discussion then turned to Terrence Malick’s The Thin Red Line. The Australian locations featured very difficult, uneven terrain, so Toll used an Akela Crane. The crane’s arm was so long (75ft) that the arc of its movement couldn’t be detected on camera. Its use had to be carefully planned though, because each time it needed to be moved it had to be disassembled and reassembled on a special platform. 80% of the filmwas actually handheld, and Toll operated himself so as to respond to the spontaneity and improv which Malick encourage from his cast.
Toll told a funny story about a shot of shadows moving across long grass which was praised by critics. It was inserted to cover a continuity error, the build-up to the battle having been shot in heavy cloud, while the battle itself was shot in full sun. A happy accident!
Time was running short, so the moderator powered through Almost Famous (where parallels were drawn between the explosive battle scenes of Toll’s earlier movies and the crowd scenes at the rock concerts, punctuated by flashing cameras), Vanilla Sky and Billy Lynn’s Long Halftime Walk. This latter film, directed by Ang Lee, is notable for its acquisition in 120fps 4K stereo. You can read more about it on the British Cinematographer website.
Panasonic Seminar: Varicam Experience
I remained at the MCK and, meeting up with Dave and Matt again, finally got into the auditorium, for the Panasonic seminar. Moderated by British Cinematographer‘s Ronnie Prince, the panel brought together a trio of DPs who shoot Netflix shows on the Varicam: Bobby Shore, CSC (Anne with an E), Pepe Avila del Pino (Ozark) and Patrick Alexander Stewart (Arrested Development).
Both Shore and del Pino admitted that they were most comfortable with the Arri Alexa, but due to Netflix’s strict rules on 4K acquisition (the Alexa tops out at 3.2K) they had to find another camera. They plumped for the Panasonic Varicam, a 4K camera best known for having dual native ISOs: 800, in common with the Alexa, Red and many others, and 5000, two and two-thirds stops faster. Being native, both ISOs have the same dynamic range, the same log curve and in theory are equally clean.
Panasonic, I think, were keen to push ISO 5000 in this seminar, but unfortunately Shore and del Pino shot almost exclusively at 800. Stewart did shoot Arrested Development at 5000, interiors and night scenes at least, but down-rated it to 2500. Otherwise, he said, the sets would have been too dark for the actors to feel like they were in a believable daytime environment. I think that’s a fascinating, unexpected side effect of low light sensitivity! Stewart lit the stages with large Quasar softboxes and paired the Varicam with Fujinon zooms and occasional Xeen primes.
Del Pino chose Zeiss Super Speeds for night scenes and Hawk V anamorphics for day scenes on Ozark. He liked the claustrophobia of cropping the anamorphic images to 2:1, the show’s delivery ratio, while the Super Speeds produced a creaminess he found appealing. He also mentioned that the Varicam’s sensor handled greens very well, which was important for him, given how much of Ozark takes places in woods.
Anne with an E was lensed on vintage Panavision Standard and Super Speeds – “the oldest, craziest lenses we could find,” says Bobby Shore. He liked their low resolving power, their weird flares and how they fell apart when wide open. Part of the show’s signature look are ECUs of the freckled title character, which were captured on a 27mm Primo for a more detailed, tactile image.
Inspired by the work of Robbie Ryan, BSC (Wuthering Heights), Shore kept the lighting naturalistic, mixing tungsten and HMI sources on a set that was treated like a location. He also shot through a Panaflasher, a special lens filter with built-in lighting which reduces contrast and adds a colour tint of your choice, but this effect was dialled out in post. Indeed, Shore raised the issue of DPs’ images being altered after the fact, an issue I explore fully in another Red Shark article.
By the way, I’ve been watching Anne with an E since the festival and I can thoroughly recommend it.
When the seminar was over, I went for dinner with Dave, Matt and Chris Bouchard, at a very nice (but once again cheap) Asian fusion restaurant. Then we met up for drinks with some of the reps from Red, and I got talking to a DP who had shot squid from a submarine for an episode of Blue Planet. After another drink or two with Chris at the Cheat bar, I called it a night.
Tune in next week for the final part of my Camerimage blog.
This week I attended Camerimage for the first time. Centred around the Opera Nova theatre beside the river Brda in Bydgoszcz, Poland, Camerimage is an international film festival celebrating the art of cinematography. It’s a bit like Cannes for DPs, but colder. This is the first part of my account of my three days at the annual hub of motion picture imaging.
The Ryanair flight was dirt cheap but trouble free, and at 9:50am I found myself on the tarmac of Bydgoszcz airport. There I met David Shapton and Matt Gregory, founders of Red Shark News, for the first time. I’ve been contributing articles to Red Shark for a few months so it was nice to finally meet these gentlemen in person.
A taxi (also dirt cheap) dropped me at the Opera Nova – only about three miles from the airport – where I picked up my pass and goodie bag. Bizarrely, said goodies included an Ikea catalogue. How did they know that us DPs love flat-pack furniture so much?
Canon Workshop: Stephen Goldblatt
From the Opera Nova I hurried to a college across the river, where the sports hall formed the venue for a Canon workshop run by Stephen Goldblatt, ASC, BSC, the man behind the lens for the likes of Lethal Weapon 2 and Batman Forever. The blurb for this workshop described Goldblatt as “a master of low light shooting”, and it was certainly pitch black when I walked in a few minutes late, and gingerly picked my way around to the far side of the hall to find a seat.
On a purpose-built bedroom set, Goldblatt was recreating lighting from the Robert Redford / Jane Fonda romantic drama Our Souls at Night, shot on the Sony F55 and Canon C300 Mark II. To practical lamps on either side of the bed he added egg-crated tungsten soft-boxes to beef up each one. He simulated moonlight through an imagined off-camera window by placing a lace curtain in front of a blue-gelled lamp and blowing it gently with a fan. An additional egg-crated soft-box provided a low level of blue toplight.
As he worked, Goldblatt revealed how he doesn’t miss ceulloid, loving how relatively easy it is now to light night exteriors or moving car scenes. “But just because you don’t need much light,” he cautioned, “it doesn’t mean you don’t want to control it.” Other developments coming down the pipe do not inspire him so much; he feels that high resolutions and HDR are unnecessary, pushed by marketing people rather than creatives.
He placed great emphasis on the importance of the eyes. “A common failing of newer DPs is that they worry more about the set than the eyes,” he said, before explaining how he will often walk beside the handheld camera with a torch, providing eye-light. He also stressed the importance of eye-lines. Although in any one shot it’s not that important how wide or tight the eye-line is, or how high or low, across the two hours of a feature film the decisions have a cumulative effect.
Goldblatt no longer uses a light meter. “Trust your eye, develop your eye,” he advised, adding that you must have a strong voice to remain in control of the images through postproduction.
After grabbing lunch, I returned to the Opera Nova to browse the exhibition hall. This closely resembled a mini BSC Expo or Media Production Show, with all the major camera and lens manufacturers displaying their wares, along with several lighting companies. I had a play with some of the cameras, including the actual Alexa 65 used on Rogue One.
Then I met up with Chris Bouchard, one of The Little Mermaid‘s two directors, who had arrived in Poland the previous day. We sauntered over to another venue, the MCK Orzeł, an independent cinema with a nice, chilled, film-buff-friendly atmosphere. The auditorium itself was packed though as we settled in for a seminar on “The Future of Digital Formats”.
Red Seminar: The Future of Digital Formats
Promoting Red’s Monstro sensor, the session was mostly about the benefits of shooting in high resolutions, and giving yourself the maximum flexibility in post. You can read my thoughts on both of those topics in upcoming Red Shark articles.
One of the speakers, Christopher Probst, ASC (DP of Mindhunter and technical editor of American Cinematographer magazine) made some interesting points about ISO. “Traditionally, low ISOs were used for bright scenes like day exteriors, and high ISOs were used for darker scenes like night exteriors,” he explained. “That was based on reducing the grain, getting the cleanest possible image on film.” He advised the opposite for digital capture. “Use a low ISO for nights to get more shadow detail, and a high ISO for days to get more highlight detail [in the sky, for example].”
Another interesting nugget came from Markus Förderer, BVK. On Independence Day: Resurgence he switched between spherical, 1.3x anamorphic and 2x anamorphic lenses depending on the situation. For example, flatter lenses were better for wide shots – where anamorphics would distort straight lines – and for VFX work.
Hawk Vantage Seminar: Top cinematographers tell their Hawk stories
I ducked out of the Red session early so that I could pop back to the Opera Nova for the Hawk Vantage seminar, bumping into my Perplexed Music gaffer Sam Meyer on the way. Hawk were launching three new sets of lenses: MiniHawk (T1.7 hybrid anamorphics), Hawk Class-X (T2.2 2x anamorphics) and Hawk65 (T2.2).
The MiniHawks in particular seem very exciting. Daniel Pearl, ASC showed us some stunning frame grabs from the upcoming Dennis Quaid vehicle Motivated Seller, shot using these lenses on Alexa Mini. Whilst having key advantages of spherical lenses (speed, small size, low weight, extremely close focus) the MiniHawks have a unique and beautiful cigar-shaped bokeh.
While Pearl had used the latest Hawks, Magdalena Górka, PSC had shot with some old ones, the C series, for Brad Silberling’s drama An Ordinary Man. “I had to frame everything centrally because that’s the only place that was sharp!” she laughed. Also addressing focus fall-off, Andrzej Bartkowiak, ASC (Speed, The Devil’s Advocate) stated, “I like anamorphic because the shallow depth of field allows you to direct the viewer’s eye more.”
Stuart Dryburgh, ASC (The Secret Life of Walter Mitty, Bridget Jones’s Diary) talked about shooting 1.3x anamorphic. He has done this on three-perf 35mm (to achieve a Scope aspect ratio), on an Alexa in 16:9 mode (again for 2.39:1) and on an Alexa in 4:3 mode (to get 1.85:1). He also recommended shooting on Super-16 with 1.3x glass, citing the example of Ed Sheeran’s “Thinking Out Loud” video, which Pearl shot.
Peter Flinckenberg, FCK (Upswing, Concrete Night) noted that, with the shift to digital acquisition, the DP is no longer a magician, “but you can bring back that magic with lighting and glass that has character.”
CW Sonderoptic: Exploring Large format cinematography & Leica lenses
I took my leave, dashing back to the MCK Orzeł for another lens-themed seminar, this time by CWSonderoptic, the makers of Leica. The first half of this panel revolved around a short film shot by Darius Khondji, ASC, AFC (Seven, Delicatessen) on an Alexa 65 with the new Leica Thalias.
The second half was all about Tod Campbell, DP of Stranger Things and Mr. Robot, focusing on the latter show. The second season of Mr. Robot was shot on Leica Summicrons after Campbell found that the Cookes used on season one distorted the many straight lines which became such a key part of the show’s unique look. “I look at season two as kind of the birth of the photography for the show,” he said. With a laugh he added: “Sorry that the lighting looks like shit in season one. I was learning!” (See my spherical lens tests for my own thoughts on Cookes and Leicas.)
Campbell revealed that season three of Mr. Robot has a different look again, using much more camera movement and “twice as much atmos”. For this season he paired Canon K35 glass with an 8K camera, but due to the Canons’ low resolution he employed Leica Summiluxes for the wide shots.
He also shared some interesting information about his testing process, admitting that he doesn’t really know how other DPs test. He doesn’t use charts, he just makes it up. He always includes a candle, a practical lamp, some kind of highlight in the background, and random foreground objects (as background bokeh can differ from foreground bokeh).
Christopher Doyle Seminar
When the Leica seminar ended I went back to the Opera Nova, where Chris and I had dinner at the nice (and once again cheap – are you detecting a theme?) restaurant. Despite having got up at 4am (3am local time) I wasn’t feeling too tired, so we headed upstairs to the 10pm seminar by Christopher Doyle, HKSC (Hero, Lady in the Water). Many people were nursing beers, including Doyle himself, and the lecture theatre was dimly illuminated by mood lighting. Clearly this session was not going to be like the daytime ones.
“We’re going to fuck things up,” Doyle began, dispelling all doubts. He proceeded to talk disjointedly but entertainingly about his work on The White Girl and what I think was a separate film about a camera obscura. His oratory was liberally sprinkled with great one-liners, a few of which I reproduce here for your edification:
There are only three people in filmmaking: the actor, the audience and the cinematographer in between them.
If actors don’t feel loved, the performance will not come across on camera.
Give the idea the image it deserves.
[Vittorio] Storaro [legendary DP of Apocalypse Now amongst others] can’t tell you how to do it. You have to find it for yourself.
People in space – that’s what cinematography’s about.
The location is very important. It gives the energy, it imposes the style.
The lens doesn’t matter; it’s what it shows that’s important.
You never sleep because you care too much – that’s what filmmaking is.
Doyle also picked up on a piece of dialogue from a clip he screened: “What is it?” / “I don’t know yet.” It was a great summation of finding the essence of a shot, he said.
Having had our fill of aphorisms, Chris Bouchard and I slipped out to get a drink. The Cheat, the pop-up bar across the road, was absolutely packed, and my early morning was finally catching up with me, so I called it a night. The highstreet of Bydgoszcz was quiet and chilly as I walked briskly to my hotel, curiously located down a service road behind the city’s football stadium, reflecting on all that I had learnt that day.
Tune in next week for tales from my second day at Camerimage.
This year I’ve shot a couple of productions on the Sony FS7, a camera I’ve been very impressed by. Its most interesting feature is its high native ISO of 2000, which makes quite an impact on how you go about lighting. The light shed by practicals is often enough to illuminate a scene, or a large part of it, and sometimes you need to take existing practicals away in order to maintain contrast and shape, similar to how you take ambient light away (negative fill) when shooting exteriors.
It’s a strange thing about being a DP that, yes, sometimes you’re required to plan a mammoth lighting set-up using tens of kilowatts of power, but other times it’s just a case of saying, “Take the bulb out of that sconce.” You’re working to exactly the same principles, using your creative eye just as much in both scenarios.
Let’s look at some examples from a promotional film I shot with director Oliver Park for Closer Each Day, an improvised stage soap.
Our location was a pub, which had a large number of existing practicals: mainly wall sconces, but some overheads above the bar and in the corridors too. The film had to be shot in a single night, entirely on Steadicam, with some shots revealing almost the whole room, and to further complicate matters I was a last-minute hire due to another DP having to step down. Keeping the lighting simple, and avoiding putting any “film lights” on the floor where the roving camera might see them, was clearly the way to go.
I identified the darker areas of the room and added a few extra sources: two blue-gelled 800s outside the windows, an orange-gelled 1×1′ LED panel in the wood-burner, an LED reporter light in one key corner, and a small tungsten fresnel toplight onto a key table, firing down from the mezzanine so it would never be in shot. Other than those, and a low level of fill bounced off the ceiling, we relied exclusively on the existing practicals. (They were mainly fluorescent, and ideally we would have reglobed these all with tungsten, but it wasn’t possible.)
So, that’s the “positive” lighting. Here are three examples of “negative” lighting in the film…
When Big Dick Johnson (yep, that’s the character’s name) first enters the pub, I put a piece of tape over a little halogen spotlight just above his point of entry. This was partly because it was very bright and I didn’t want him to blow out as he walked under it, but it also made for a much better sense of depth in the overall shot. As I’ve often mentioned on this blog, the best depth in an image is usually achieved by having the foreground dark, the mid-ground at key and the background bright. Killing the halogen spotlight helped create this progression of brightness and therefore depth. It’s also just nice in a shot like this to come out of darkness into the light, enhancing the reveal of the new space to the viewers.
When Billy De Burgh scrambles to buy a ticket at the box office, there are two practicals just above his head. Depending on which way we were shooting, I de-globed one of the fixtures – always the one closest to camera. This ensured that Billy always had backlight, and never had a really hot, toppy front-light shining harshly down on him.
On a side note, the blue light inside the box office was existing – I guess they were using cool white LED bulbs in there – and I really like the way it differentiates the spaces on camera. It puts the bored ticket-seller in a cold, detached world very separate to Billy’s warmer, more urgent world.
This doorway where Big Dick ends the film had sconces on both sides. It’s never very interesting to have an actor evenly lit on both sides of their face, and especially as Dick is such a tough, unpleasant character, I felt that more contrast was required. I chose to remove the globe from the righthand sconce, so that when he turns camera left to look at the sign he turns into the remaining sconce, his key-light. We filled in the other side of his face a tiny touch with a reflector.
I would love to have been able to exercise the same control over the street-lamps in the opening scene of the film – some of them are quite flat and frontal – but unfortunately time, budget and permissions made that impossible. We would have needed huge flags, or a council-approved electrician to switch the lamps off.
That’s all for today. Next time you’re in Bristol, check out Closer Each Day. I didn’t get chance to see it, but I hear it’s brilliant.