... I was wondering if anyone can give me advice on lighting using the sun and the optimum times for shooting during the day/ getting night shots over a city but using some light from the sky, like in the photo's from 'Her' that i have placed below (mainly focusing on the screen shot of the rooftop over looking the city).
This is an example of dusk-for-night, which is an important technique for indie filmmakers to learn because it is a means of obtaining expensive looking production values for very little money. Dusk-for-night uses the fading daylight as an ambient fill to gain a base line exposure in wide establishing shots without using a big source. Typically it is intercut with closer framing shot night-for-night to create a realistic night scene. The advantage to shooting dusk-for-night over day-for-night (the other low budget alternative to expensive night-for-night cinematography on a large scale) is that if you are shooting a house or city street you can incorporate set practicals like window or porch light, car headlights, or even streetlight or raking moonlight in a wide establishing shot. But in order to get the balance right between your lamp light and the fading daylight requires the right location and careful planning.
For example, the key to success in shooting the house pictured below dusk-for-night is choosing the right location. To get the subtle separation of the night sky and trees from a dark horizon, you don’t want to shoot into the after glow of the setting sun. Instead you want to find a location where you will be shooting into the darker eastern sky. With dusk-for-night, you have maybe a thirty-minute window of opportunity after the sun has set to shoot the wide master before the natural ambient light fades completely so you have to have everything planned out, rehearsed, and ready to go.
In order to get the balance right between the practicals and the ambient dusk light in the limited time you have to shoot the establishing shot, you have to start with larger fixtures and be prepared to reduce their intensity quickly. For instance if you want the glow of an interior practical light raking the lace curtains in a window, start with a PH213 in the practical and 2k Fresnel raking the lace curtain. Wait until the ambient dusk level outside has fallen to the point where the balance between the natural light and your lamp light looks realistic and then roll. To get a second shot or take, open the camera aperture a half stop and drop a single in the 2k head, dim down the PH213, and wait again until the ambient dusk level outside has again fallen to the point where it looks realistic and then roll. If you continue in this fashion with nets after you have exhausted your scrims, and a PH212 when the dimmed PH213 starts to look too warm, you will be able to get multiple takes out of the diminishing dusk light.
Likewise with a streetlight or moonlight raking across the front of the house. To create a moon dapple on the front of a house against a night sky, you will need a good sized HMI set on a high oblique angle so that it will rake across the front of the house. Break it up with a branch-a-loris and wait. When the ambient level of the dusk sky has fallen to the point where it looks realistic against the moonlit house and the practical lit interior - roll. You can even add a car pulling up to the house, but you have to be prepared and have enough manpower standing by to dim the practicals, net the lights, and scrim the car’s head lights very quickly. The final touch is to use a graduated ND filter on the lens to darken the sky and balance the camera between daylight and tungsten so that the ambient dusk light filling the shadows is cool and the practicals and tungsten lights motivated by them remain warm but not too warm.
Once dusk is past, you shoot the close coverage night-for-night when a package consisting of what you can run on a portable generator will suffice. If you parallel two of the Honda EU7000is generators for 120A output, you will be able to use a 6k HMI for your moonlight at dusk on top of a sizeable tungsten package to light the interior of a house to a high level to match the daylight. For example, the scene below takes place in the middle of a near vacant parking lot of an all night convenience store. The establishing shot of the brightly lit convenience store situated in a wide-open expanse of a empty parking lot at night was shot dusk-for-night because the production didn’t have the resources to light up the parking light and building to separate it from the night sky. Close coverage was then shot night-for-night with nothing more than a single modified 7500W Honda EU6500is and a small tungsten package of 1ks and 650w Fresnels.
With no building or other sound barrier within a reasonable distance to block the sound the generator, Gaffer Aaron MacLaughlin had no recourse but to put it behind their grip truck as far from set as possible. This was only possible because he used a transformer to step down the 240V output of the generator, and in the process compensate for the voltage drop they experienced over the 500’ cable run to set.
Guy Holt, Gaffer, Screenlight and Grip, Lighting rental and sales in Boston.