Why night panos are such a challenge
In my previous post, I noted that I had not done many night panoramas of Burning Man. I thought I should outline just why they are such a challenge.
To shoot at night, you need a time exposure, typically a second or more. You can capture lights and fires with far less, but if you want to capture the things illuminated by those lights and fires, you need a long exposure. Having both the light source and the illuminated subject in a shot is like shooting into the sun. There are a few things you can do to get away with a shorter exposure, but they don't work well for this sort of work.
- You can bump the ISO on your camera. If you do that, you make the picture more noisy. This ruins it when you try the next technique...
- You can apply curves in photoshop to brighten the shadows but not brighten the highlights, which tend to be much brighter than the shadows, because they are the light sources themselves. But if you used high ISO, you will immediately highlight the noise. You can't do both.
- You can be tricky about how you do your curves. I recommend first using colour range select to mask out the actual light sources and areas near them (highly feathered) and then do your curves so you are not brightening the area right next to the lights at all.
- You can use a fast lens, wide open. But if you do this, you will get a shallow depth of field, meaning that if the foreground is in focus, the background is blurry, or vice versa. Problem is, for panoramas, trying to capture a large sweeping area, shallow depth of field is not a good idea. My daytime panos are shot at f/8 or f/11.
So you're stuck with a long exposure. Right away that's going to cause a problem with moving things, notably people and vehicles. There is simply nothing you can do about this with a long exposure, unless you can command the world to stop.
- I like to shoot panoramas from up towers, to capture the whole city. But towers at Burning Man are rarely built super-stable. They are usually scaffolding. If other people get on them, they wobble. That ruins almost any length of exposure.
- Over the years, the only really stable platforms have been the man, when he was a pyramid, and the Black Rock Refinery of 2002. Other platforms would be stable if I could get them to myself, but that's hard at Burning Man.
- A boomlift can be good if you get it to yourself. But nobody on the boomlift can even shift their weight while the shutter is open.
- In the dark, it's easier to make mistakes, like leaving autofocus on. Or if you are doing manual focus, it's much harder to do it. The autofocus often doesn't work, and your eyes may not have something good to focus on either.
- If what you are shooting is lit by fire, then the lighting is going to change form one frame to the next!
Now it gets worse. Since a full panorama like I take uses 36 shots, to get a perfect pano, every single one of them must be good. And that's not going to happen. So you tend to take each shot 2 or 3 times, and hope that one of them works out. Problem is, the longer you wait between moves of the camera, the more likely something in the scene is going to move between frames, causing a blending problem.
You can check on the camera screen if the shot came out, but that's very time consuming and just makes the moving car problem even worse. I have wished for some time that cameras had a review mode that was "Show me a full 1:1 pixel zoom of the region of the photo with the highest contrast and sharpest edges." If that region is blurry, you know your photo is blurry. If that region is not your subject, you know you had bad focus. A button to cycle through the sharpest edges in the photo would help confirm this.
Some Nikon cameras had a mode to do this automatically -- take 3 photos, and save the one with the least blur. I wish that mode appeared on my cameras.
So all in all, it's a wonder they work at all sometimes. This year I had high hopes, because one crew built an 11 floor tower out of giant steel I-beams. But it wobbled a great deal at the top with all the constant traffic. It didn't wobble as much on lower floors, but sadly at night they put up a giant screen and projected rather uninteresting photos onto it. The combination of the screen, and the projector light shining right at you, made photos from the stable levels impossible.