Rocket Launch Photography Challenges



Two successful SpaceX missions last week, one on each coast, prompted me to review my rocket launch photo procedures, particularly since the Monday (Sept. 13) launch from Vandenberg Space Force Base was the first after a long hiatus. For those of us in southern California, it was a photo op we were eagerly awaiting since it was scheduled for after sunset.

Daytime launches hold little appeal for viewing from a distance. A little white dot against a blue sky doesn’t excite anyone, so for these, a position close to the launch site is needed. However, sunset launches have great potential to provide an impressive show in the sky visible without having to go anywhere beyond your backyard. Unfortunately for us in southern California, launches of any kind are much less frequent than in Florida, making climbing the learning curve of rocket photography a much longer process.

As in many other types of outdoor photography, getting a good shot involves several common elements: location, lighting, and weather. For rocket launches, astronomical circumstances (Sun and Moon position and Moon phase) also matter. This month’s Vandenberg launch was not quite favorably timed for photography, so while it was widely visible, photographically, it was a bit disappointing.

Vandenberg SpaceX Launch Shooting Challenges

When a rocket launches, there is a natural desire to get as close to the launch pad as possible. With special permission, it’s possible to place equipment as close as a quarter mile or so, but I won’t cover this because it takes a special setup as the equipment has to be unmanned (automatically triggered) and potentially has to sit in a position for 48 hours in case of launch scrubs. Heat, cold, dew, and external battery hookups become real additional challenges.

At Vandenberg SFB, the general public is allowed to get as close as three miles away as the crow flies. But in this case, the crow has to fly over intervening hills. From the publicly accessible viewing points, the launch pad itself is not visible. Even at an alternate public viewing area (some nine miles away), the base of the SpaceX rocket is not visible. In addition, the launch site is often prone to being covered by thick marine fog, though this does not prevent the actual launch. Also, at these distances, the rocket can go so high (you’d swear it was directly over you) that a normal video pan head can run out of vertical travel! But despite this, if the first stage booster is landing back at Vandeberg, it’s worthwhile to experience both the sights and roar of liftoff and the booster return with accompanying sonic booms.

On many SpaceX launches, the first stage lands on a special floating landing barge out at sea. While the actual booster landing is too far offshore to photograph, it’s possible to see the booster make its reentry burn before hitting the thickest part of the atmosphere. For this reason, an alternative to photographing a launch from close to Vandenberg SFB is to position yourself further downrange so the entire launch path is visible.

The initial (first stage boost) phase seems relatively straightforward to capture — a single very bright target to follow. But in practice, keeping a moving target centered when shooting photos is challenging at high magnification. A moment of inattention can cause you to lose the target and have to spend valuable time trying to recenter it. For this reason, a zoom lens is much more desirable than a fixed focal length telephoto lens or telescope.

 After the main engine cutoff, another problem can pop up — with no visible rocket flame, it’s easy to lose track of the rocket position if you’re at high magnification. After the second stage ignition (several seconds later), there are then two objects to follow, which are gradually separating.

As the second stage continues to accelerate, it produces a widening plume. Meanwhile, the first stage is inside the plume, actively setting itself up for a landing, but is more difficult to spot because it is only firing cold gas maneuvering thrusters. On top of this, shortly after the second stage ignites, the payload fairing halves may be visible, making two more possible targets (or distractions).

The best photogenic conditions are when the vehicle launches just after sunset. But this complicates exposure choice since the darkening sky, possible entry of the rocket into direct sunlight, and the extremely bright first stage plume make it a challenging exposure tradeoff decision. I generally keep my exposures fairly short (faster than 1/60 sec.), necessitating a high ISO in a darkening sky, with the final choice made just before the launch based on test shots of the sky background brightness.

SpaceX Launch Shooting Strategy

Because of the potential difficulties with tracking the launch with a telephoto setup, I use a wide angle (15mm) fisheye lens as a backup to ensure that I don’t come back empty-handed. This setup is positioned so that it can cover the entire visible flight trajectory without having to be adjusted. In most attempts, I’ve had the camera (a Nikon D600) snapping shots every few seconds using its internal intervalometer function. The internal intervalometer function in many Nikon cameras is a great convenience, making it unnecessary to bring along an external device.

For telephoto shots, I’ve been using a 70-210mm telephoto lens on a pan head, manually tracked. For this camera, a live view on an articulating screen seems best, keeping in mind that the vertical panning range during the launch will be extreme.

As with shooting any tiny, moving target, it’s best to set the cameras to manual focus and exposure. Exposure times should generally be short and bracketed if possible. Panning movements should be as smooth as possible (practice!).

September’s Starlink Launch

In addition to shooting telephoto shots (70-210mm zoom), I had a slightly wider lens (24-70mm zoom) on an additional camera. Both were mounted on a single tripod, which was manually tracking the rocket. The longer zoom was used to get in close to the rocket in the initial boost phase, while the wider zoom was meant to capture shots of the wide exhaust plume. The wider shots can be impressive when the plume is sunlit, but unfortunately, that was not the case for this launch and the wide shots were wasted. Both of these cameras used internal intervalometers to fire shots every few seconds as I tracked the rocket.

The backup stationary setup this time was a video setup using the 15mm fisheye lens, positioned to capture the entire flight path with real-time video. Here, I used a first-generation Sony a7S, which is the high sensitivity variant of the a7 line. Despite this camera having been replaced by subsequent generations of Sony’s family, this original model is still very capable for low-light video if the result is post-processed (more later on that).

Back in 2017, I found a seaside cliff location in Palos Verdes where the rocket was visible soon after launch and virtually the entire atmospheric part of the trajectory was visible.

The recent launch was less of a favorable photo op in several respects. The first was that the launch occurred late in the evening after sunset, so it and the rocket plume never became illuminated by the Sun. The first quarter (half-illuminated) Moon was also in the sky to the West, placing a bright distraction in the frame.

To make matters worse, while driving to the seaside location at the edge of the Palos Verde peninsula, I could see I was going to end up in a dense layer of marine fog. This marine layer extended up the coast, covering even the launch site.

Fortunately for me, the Palos Verde peninsula includes a 444 meter (1,457 feet) hill, so I retreated uphill, hoping I could stay above the fog layer. This did largely work, though a thin layer of haze persisted, exacerbating the problem of the distractingly bright Moon with a corona of scattered light.

From my final location, the wide view video picks up just before the main engine cutoff and runs for six minutes until the second stage finally disappears from view, which is near the second stage cut-off point. Around 4:30 into the video, the first stage of reentry burn can be seen. A better view of a reentry burn is visible in a shot from the 2017 launch of an Iridium payload.

Post-Processing

Generally, the static shots can be conventionally processed in applications such as Lightroom. For the video clip, however, I found that Lightroom would not open the Sony MP4 file, but Photoshop was, fortunately, able to do so. Within Photoshop, I was able to do everything I needed for simple video editing: trimming the leading and trailing footage, adding labels and arrows, cropping to 16:9 format, and even noise filtering and adjusting curves. For simple video needs, Photoshop has come a long way! The downside? To render the video, Photoshop took over five hours on my Intel i9 PC!

Got suggestions for me to improve my rocket launch shoots? Add a comment below. it will be much appreciated!



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