Panoramic images are a current hot topic in the digital photography world. For the uninitiated, a panoramic image is any image that has an exaggerated aspect ratio; much longer (or taller) than it is wide. You can produce panoramic images in one of two ways:
- Cropping
- Stitching
While cropping can work great, you throw away image resolution when you do it. With stitching, you need to take multiple images and blend them together. Doing so gives you images with far more detail than you’d get from any single image frame. Consider a simple stitch with two shots from the 16 megapixel Nikon D7000, which produces a 4,928 x 3,262 pixel image. Simply by combining two shots end to-end, you’d get a composite image that was at most 9856 x 3262 pixels– 32MP.
The trick with shooting panoramic images is that to get everything right, the two images must be properly aligned. Without good alignment, the stitched images will be curved, forcing you to crop away many of those precious pixels. First, your camera needs to be perfectly level. That can be tricky to do in the field for landscape shots on uneven terrain. Second, if you can do it, your camera should rotate around the lens’ optical center (sometimes referred to as the nodal point) and not the camera body. Rotating the camera around anything other than the lens nodal point will result in another form of distortion: parallax. Parallax distortion is where near objects appear to change position in the frame as you rotate the camera. This will lead to ghosting in the stitched image.
Fortunately, there are lots of manufacturers who have embraced panoramic photography and provide kits to help you mount your camera on a tripod, level it, and adjust its position so that the point of rotation is on the nodal point of your lens. Unfortunately, these kits are expensive.
For years, I’ve been using the Really Right Stuff panoramic clamp and nodal slide. While it’s not the fanciest kit for panos, it is very easy to transport and it works with the Arca-Swiss style camera plates that I so dearly love. RRS (and others) also make components that allow you to do multi-row panos.
To make a multi-row pano, you need to not only rotate the camera around the lens axis in the horizontal plane, but also in the vertical plane. That means more expensive parts to buy. It also requires practice, as you’ll need to shoot 2 or 3 images in the vertical axis for each horizontal position. That can get complicated.
So why would anyone want to spend this kind of dough on such specialized gear? Well, some people are obsessed with megapixels. When you start stitching 12 or 15 images together, the resolution gets big. A 12-shot stitch I made with my D3s (12Mp) weighed in at over 160 megapixels! And that’s chump change compared to what the pano-geeks are doing over at Gigapan.org! For me, the biggest problem with these HUGE images is that there isn’t a good way to display them (that’s why the Gigapan site is nice; it lets you zoom in). I mean, unless you print these things BIG, you’ll never see the detail that was recorded.
There is, however, an advantage to making small stitched pans. Consider the scenario where you orient your camera vertically and make only two shots on the horizontal axis. Doing so preserves (mostly) your native 3:2 aspect ratio, but you can go from a 12MP image to a 24MP image (give or take, depending on the amount of overlap) with a relatively small investment in software and tripod hardware. Compared with the price of Nikon’s flagship D3x DSLR, and suddenly that investment doesn’t look so bad.
- Nikon D3x (24MP camera): $7999 (MSRP)
- RRS Single-row Pano system: $360
- PTGui Pano Stitching Software: $121
So, you can fork out roughly $500 for a basic pano kit and software, which you can use with any camera you own, or drop nearly eight grand on a 24MP DSLR. Take your pick.
There’s just one teeny problem with making single-row panos with my basic kit. You have to have the camera perfectly level. Too often, I found myself in the field with a horizon smack across the center of the frame. Oh, how I’d wish I could just point the camera down or up to put that horizon on a rule of thirds line. Here’s where that multi-row kit comes into play. With the multi-row pano kit, you aren’t required to shoot multiple rows of images. With the camera’s rotation point oriented around the lens in both the x and y axes, however, it means that you can point the camera up or down and get a perfectly stitched image. Better stitches mean that you can keep more megapixels. Life is good.
While the full-on multi-row kit from RRS will set you back $900, it’s built to last. When you upgrade your camera, you keep the pano system. And hey, you can still do the multi-row thing and produce 100 Megapixel images. That’s a lot less than dropping $48,000 on a Phase One 80MP camera!
You can learn more about stitching panos in The Photographer’s Guide to Digital Landscapes.
I use PanoEdit for Mac to stitch images (www.panoedit.com). It has very simple interface and works well.