A couple of weeks ago when I was in Utah I experimented a bit with panorama photographs. I didn't have much to work with since, as I mentioned at the time, I had decided to leave the good camera home in order to make room for some (ultimately useless) hiking boots and other equipment.
So I played around a bit, trying to keep everything lined up and level as much as possible just by eyeballing it on my pocket digital's tiny screen. In the end I got four of them, all taken on my second day there, in the general environment of the Snowbird resort.
Snowbird from the balcony of a lodge where I had dinner. One thing I notice about panoramas which is true of all wide-angle perspectives is that the perspective tends to make the mountains look a lot less steep than they are. Virtually everything left of the middle is advanced or expert terrain, though it doesn't quite look that way.
The western panorama from Hidden Peak, at the top of the Snowbird Tram. The Salt Lake valley is off to the right under the haze. Note the skier walking back up on the far left. He's just skied the Little Cloud bowl's north-east facing slopes, then walked back up the opposite side where there wasn't much snow. At this time of year, walking back up to take the tram down is a lot easier than walking down 2/3 of the mountain through varying terrain and conditions.
The eastern panorama from Hidden Peak, at the top of the Snowbird Tram. Alta is just past Mt. Baldy, which is the closest big peak. The terrain to the left is part of Snowbird's Peruvian Gulch and the terrain to the right is called Mineral Basin. You can just barely make out the cables for the Mineral Basin chairlift at the very far right.
A few learnings here.
First, I noticed that when the autostitching software put the 4-6 images together into a single panorama, I often get dark bands where the images come together. I had to go back to the source images to figure out what was going on. Naturally with a small automatic camera the exposures of the various segments were somewhat different, and especially when those images included very bright sections like snowfield. The software has to reconcile two images whose exposure is different. There's no perfect way to do this, and the result is unevenness and sharp cutoffs in places, which become more noticable the more images are included in the panorama. Panoramas with fewer images( like the one of the tram), or with similarity of lighting and subject matter (like the one of the Snowbird base) show this effect a lot less.
[Note that I did some quick and dirty Photoshop dodging to remove the most offensive of these dark bands, but they're still there if you look carefully, particularly in the sky.]
The answer to this is pretty simple. I need to do these images with the SLR, I need to meter all the segments of the scene, and then I need to pick a single exposure that works well enough for all the sections. I also need to take the images in a very short period of time, particularly if clouds are cutting in and out or the light is changing in any other way. I suspect that for broad panoramas, a gray card on the ground or an incident meter would work best. For a 360 degree panorama, I'd probably just have to measure with the card flat on the ground or the incident meter pointed straight at the sky. For 180 degrees, I'd just meter with the card or meter pointed straight out of the center of the scene. And until I really get the hang of it, I'd probably bracket.
The second issue is of keeping the images aligned with each other, so nothing is lost. For example, in the panorama of the tram, much of the tram cabin is cropped out, not because it wasn't in the original image, but because the adjacent images weren't lined up. The "common" rectangle lost some off the bottom of that segment, as well as some off the tops of the others. The coverage of the original images looked like this. Really Right Stuff make a wonderful device for this as well as even more sophisticated equipment for use in multi-level panoramas. Probably a bit out of my league, but I suspect I could come up with something pretty good using a spirit level on my existing tripod and rotating head.
Finally, I've got to thank my friend Leo, for introducing me to the freeware Autostitch. The software definitely has some issues, most notably in that it only handles jpeg images at this time, but it's pretty fantastic stuff and given the size of the images created from merging 5-10 full size photos, the use of jpeg in place of an uncompressed format is not all that big a deal for me right now.
-btc
