Landscape photographers have enjoyed a love affair with large format cameras. I am speaking of 8 x 10 inch and 4 x 5 inch film cameras, commonly referred to as view cameras. My first one was a Calumet model and later a Sinar P2 4×5. One could make huge prints from the large negatives and slides. The drawback to large format view cameras is the weight of the camera and the tripod. Field cameras are lighter and reflect that in additional price.
This topic will be in two parts, one for single-row stitches and the second for multi-row stitches. Single-row stitches are not as complicated and have less equipment requirements. Multi-row stitches with its additional hardware requirements, are more complex and are more beneficial to the architectural and fine art landscape photographer.
Today we can create similar high resolution images with software, and not that goofy interpolation stuff, that is for the birds, lol. Interpolation creates additional pixels by sampling the nearest neighboring pixels and manufactures what should be there. Interpolation is fine for a 50% or 100% increase in print size. For truly stunning 200% and larger prints, I prefer the image stitching method. Stitching software takes two or more individual images and combines them as a single image by aligning and finding control points and nodes in the series. Think of each individual image as representing a black or white square on a checkerboard.
We will be discussing two types of stitches that I do, the single row and the multi-row. There is a third type which is a 360 or 180 degree multi-row stitch, but I do not use it due to the image distortion. You may have seen this third type used for real-estate websites and ads. I am more interested in creating very large 30×40 inch prints, that are distortion free, sharp as a tack, and extreme detail.
A little company in France makes a great program called AutoPano Pro. We call this stitching software or panoramic compositing software. The only requirement is that you have a fairly powerful computer and lots of memory. It will work on a 2.16 Core 2 Duo Mac Book Pro with 4 gigs RAM just fine. My new computer a 2.8GHz Mac Pro with 8 processors and 8 Gigs RAM obviously runs this program much faster. My suggestion is to have at minimum a Core 2 Duo processor and 2 Gigs RAM. A three image stitch may take 8 minutes to complete at this minimum computer requirement.
Single-row is a series of images from left to right with no elevation changes. Multi-row is a series of images left to right as well, except we change the camera angle or elevation. For example, we take three images with the camera angled up, left to right, including the horizon line. Next we return to the first left camera position from before, and shoot a second series. This time the camera is angled down, still including the horizon line, and shoot a second series of images from left to right. Yes, as you may have guessed, a multi-row is the same thing as two single-row. We are overlapping each image by 25% both horizontally and vertically. So while a single-row stitch may have 3 images, a multi-row will have twice that…or 6 images.
Three very important first steps before you even begin to attempt this. Do not use a POLARIZING filter for stitches, individual image edges will have an uneven exposure. Put your camera in MANUAL FOCUS and MANUAL EXPOSURE. If the camera lens is AF focusing on different points during the series, your images will not line up properly. Same thing applies for auto exposure, different F/stops have different fields of view and that will change image size as well as exposure from image to image. Obviously exposure differences are minimal on distant and evenly lit scenes, by why tempt fate and spend hours fixing it up later. Been there, done that.
Single-row is the easiest way to learn and can be done with a simple tripod. First get your tripod and camera level using a bubble level. Don’t have a bubble level, buy one for $20 at any camera store. These levels slide into your cameras flash hotshoe. With my camera mounted vertically (portrait orientation) on the tripod, I shoot several images from left to right with a 25% image overlap. Most cameras have a set of horizontal and vertical lines viewable through the viewfinder, you may have to turn this grid feature on in your camera menu. Use the grid lines to approximate 25% overlap. Easy, huh.
Why shoot left to right, can I shoot right to left. Sure you can, but the software wants the images left to right so you will have to rename the images later in Adobe Bridge so they go left to right. The software also prefers that if you shoot multi-rows, that you shoot the top row first and then the bottom row. Don’t question it or argue with me, just do it and the stitching process will go much smoother and faster later.
My camera is 12MP or 4288px x 2848px. I shoot vertically (portrait orientation) because that gives me 4288 pixels along the left edge of a print. My left to right images are 2848px each, but then we have that 25% image overlap factor, so it will be less in reality. Do not assume that 3 images stitched will be 2848px x 3 = 8544px, it will actually be closer to 6200px. So if you need more width, shoot an extra frame or two and crop later. The 4288px height will not change dramatically, maybe down to 4100.
Now in RAW processing, I apply the same develop settings to each individual series that will compose a single final image stitch. Why you ask, well, I want the same color temp and exposure to match from left to right. Don’t worry about the initial blending of the sky, it may be darker on the left side and brighter on the right side. This is the beauty of why I love AutoPano Pro. It will automatically blend the sky using very computer intensive mathematical formulas to make this perfectly seamless. Autopano Pro was also good enough to provide built in HDR and 16 bit, what more could you want.
I use single-row stitches for stationary product shots and also for select people images when I need to capture the ambiance and environment. I shoot the people subjects till I have the shot I need, then I swing the camera left and right to get the extra pano images for the stitch, simple and inexpensive.