360° Timelapse, Mowing the Lawn

I’ve been wanting to shoot a 360° spherical HDR timelapse for quite a while now. The challenges are enormous: storage space, battery power, programming the brackets and camera movements, etc. It gets quite complicated! A few months ago I bought the first Panoneed robotic head in the western hemisphere; since then I’ve helped two more people configure and purchase theirs. I’ve worked with the Panoneed designer and Promote Systems to get it working with the Promote Control, and even take a panoramic timelapse with two Promote Controls. A couple weeks ago I decided to put it all to the test while mowing my back yard. We had about a month of nothing but rain, which watered the grass well but prevented me from mowing it. It also prevented me from really doing anything practical outdoors with the Panoneed and two Promote Controls to test firmware versions. Not that a timelapse of me mowing my lawn is practical, but it seemed like a good demonstration. Here is a handheld video I took with my iPhone describing how the Panoneed and two Promote Controls are configured. Forgive the stammering, I did it off the cuff without a script while the blackflies were eating me alive! The last third of the video is the finished 10 second timelapse and then some rolling credits with more information, described in more detail below. Turn on HD if your internet is fast enough, it looks much better! The interactive sphere is near the bottom of this article.

Video

To get enough power to the camera, I bought a cheap 3rd party Nikon EH-5A AC power adapter and cut the DC cable coming out of the brick. I attached some Anderson PowerPole connectors to both ends so I could always reuse it if I wanted later. I also bought a DROK 12v to 7.5v DC buck adapter or step down converter and attached PowerPoles to both ends of that to power the camera. I cut the cable going to my 300w inverter and added yet more PowerPole connectors to both ends of that. Lastly I bought a PowerPole splitter. Now I can plug the 12v to 7.5v step down converter for the camera, an AC inverter which will have a 15v 1A DC power supply plugged in to power the Panoneed, and a dew controller and heater strip for my Nikon 14-24mm f/2.8 lens for night photography all into a portable battery at the same time for long exposure night panoramas. For this demonstration I only used the external camera power however.

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I set the lens to 14mm, f/8, and manually focused to 2.5 feet. I had meant to set it to f/9 as that would have kept everything sharp from 1.2 feet to infinity, but I forgot and left it at f/8. The trees across the pond in the distance were still pretty sharp. I set the camera to ISO 200, disabled auto ISO, and chose a custom white balance to keep exposures consistent throughout the timelapse. For exposures on the second Promote Control I chose 1/320, 1/80, and 1/20 (three exposures spaced 2EV apart) to cover most of the dynamic range. The overcast sky was still slightly overexposed, but I didn’t want to shoot more than three photos because I wanted to shoot each sphere as quickly as possible and I knew I was going to overload the 64GB memory card anyway with three brackets. I prefer to shoot my HDR brackets in 1 to 1.3EV steps, but that would not have been enough dynamic range. I didn’t want to go over 2EV either, so I let the sky overexpose a little. I also disable auto image rotation, rear LCD preview, and cover the eyepiece when I’m shooting timelapses and spherical panoramas to make stitching easier, prevent heat from building up inside the camera, preserve battery power, and keep stray light from entering the camera.

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I set the touch controller on the Panoneed to 14mm, 20% overlap, and three brackets with vibration detection enabled and 2nd curtain sync monitoring enabled. The firmware I have installed on it only sends one trigger command to the second Promote Control for each bracket, but it will write two .xml positioning files for aligning the photos in PTGui Pro or AutoPano Giga: one is a single bracket if you want to tonemap or use exposure fusion before stitching, and the other has images for all the brackets if you want to stitch all of them at once before tonemapping. Very convenient! The vibration detection will wait to shoot if there is wind or other vibrations and the second curtain sync will monitor the shutter on the camera through the PC sync port or flash shoe so the Panoneed knows the brackets have been taken and it is safe to move to the next position. You could use a fixed interval here instead, but occasionally a bracket can take slightly longer than the previous one if the camera or Promote Control are busy or a signal takes a little longer to process, and I wanted to shoot my spheres as quick as possible with no additional manual delays in the intervals.

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I took one sphere and timed how long it would take, about a minute and thirty two seconds. I put the first Promote Control in timelapse mode, “on camera” exposure (since I wasn’t sending any exposure signals anyway), disabled any warnings in the setup about a camera not being present, and set the interval to 1 minute and 35 seconds to add a small safety buffer. I was only using it as an external timer and trigger to tell the Panoneed to repeat the last panorama at regular intervals.

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For nearly the next two hours I took 2,730 photos (70 spheres) for a timelapse, and then it started raining. I paused the timelapse and covered everything up with a tarp to protect the gear. It was just as well, the 64GB memory card was getting quite full. I took an hour and a half break, downloaded all the photos off the memory card, ate some lunch, put more gas in the lawn mower, and waited for the rain to stop. The second half of the timelapse was 3,978 photos (102 spheres) over a two hour and forty two minute timespan and the memory card was full. [Yeah, it’s a very big lawn!] There were actually a few more photos from a partial panorama that I discarded.

For post processing I converted all the RAW files to 16-bit TIFFs with minor sharpening and color correction in Lightroom. Then with Photomatix Pro’s batch feature and exposure fusion I turned them into 2,028 files to stitch with PTGui Pro. I created a template and exported out 156 projects via PTGui’s batch builder. Unfortunately my zoom lens creeped a little from 14mm to 15.5mm over time, even with rubber bands on it to hold the zoom ring. I’ll have to try masking tape next time. So it didn’t matter whether I built the template from the beginning, middle, or end of the timelapse, not all of them would blend well. In the end the easiest solution was to open every project file that the batch builder created and manually enable automatic EXIF data from the camera, align the images, and create the panorama. This also gave me a chance to mask out any ghosts or duplicates of me on the lawn mower, so it was just as well I stitched each one manually. At least batch building the project files saved me a lot of time and all the panoramic frames of the timelapse came out very consistent. If you look very closely at the tiny black nadir hole in the middle of the tripod you’ll see it gradually change as the focal length creeped. 🙂

Displaying the spherical timelapse was a whole different set of challenges. KRPano can display a video in different projections, but the technology for compression algorithms and internet bandwidth is currently just not available yet. Each frame was a 50 megapixel image (10500 x 5250 resolution) and most people don’t have internet bandwidth to watch 1080p (1920 x 1080 resolution) video without stuttering. Also, anything wider than 1920 won’t play on most mobile devices like iPads. So I chose 1920 x 960 for a resolution at 24fps and 8Mbps for a data rate. It looks good when displayed flat, but when viewed as a sphere you are then dividing that resolution by 6 because you are looking at six different faces of a cube, but only one at a time. Even at a really high 8Mbps data rate for more details it displays a very low resolution when viewed at anything larger than 320 x 160. When you blow something that small up to full screen it is going to look heavily pixelated and smeared. Technology does not yet exist to my knowledge to view multiple resolutions of video on the fly so you can zoom in and get a higher resolution of only the specific area you are viewing like still images can do. Maybe in time technology will catch up. Many people don’t have fast enough internet to display 8Mbps (mine is 3Mbps), so there will be some severe stuttering until the entire 5MB video can be downloaded and looped. I chose only the second part of the timelapse I shot to cut down on filesize for the interactive video, and I reversed the frames on the second half and then looped the whole thing so you can watch the grass get cut and then grow back again. I couldn’t find a way to loop the video without a pause or stutter in the middle. Flash no longer allows for seamless video looping I guess. Mobile devices running HTML 5 instead of Flash are not capable yet of displaying 360° video in various projections, so it will only play as a flat video on them. Maybe in time with better video cards this can be accomplished.

In the meantime, click the photo below to explore the interactive spherical timelapse. Right click and try out the various video projections if you are on a desktop, such as flat, normal, and little planet. If anyone reading this is a video compression guru and has some tips to help me make it look better, I would greatly welcome your suggestions!

Panorama

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I would like to once again publicly thank both Type & Colour and Promote Systems for their generous support in helping me with this project. I have several more ideas and issues to resolve as funding allows, one of them being an 8mm or 15mm fisheye to shoot spheres faster for night photography, and figuring out how to tackle bulb ramping with panoramas and without ND filters for an unattended “holy grail” spherical timelapse. Storage will be a very big issue for that, but many obstacles were resolved with this demonstration such as external power for the camera, repeatable HDR panoramas via two Promote Controls, and second curtain sync monitoring on the same circuit (necessary for bulb ramping).

Lots more to come on this topic over time… Happy shooting!!!

Gallery

 

Equipment Used

• Panoneed robotic head with touch controller and 2nd curtain sync kit
• Really Right Stuff TVC-34L tripod
• Really Right Stuff TA-3-LC-HK leveling base with clamp and hook
• Really Right Stuff TH-DVTL-55 dovetail plate on bottom of Panoneed
• Really Right Stuff MPR-192 rail bolted to Panoneed (a B2 LR II 60mm clamp will be bolted here soon for convenience)
• Really Right Stuff B2-FAB & B2-40 clamps mounted back to back (made obsolete by the better FAS clamp today)
• Really Right Stuff BD700 camera plate
• Nikon D700 camera
• Nikon 14-24mm f/2.8 lens (rubber bands to keep the focal length from creeping)
• Sandisk 64GB Extreme Pro 90MB/sec compact flash card
• 2x Promote Controls
• Maha Powerex 2700mAh batteries for Promote Controls
• 12v car battery / charger (check out GoalZero’s new battery)
• DROK 12v to 7.5v step down converter
• Kid’s stool to keep the grass clippings out of the battery! 🙂

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