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About Panoramics...
There are hundreds of panoramics on this site, primarily starting from 2001 to present. These aren't recropped images, they're multiple exposure images joined together. If you go and look, you'll actually see how I've improved my technique for creating these as time goes on.I will one day, go back and re-do the older panoramics with the techniques I know now. I've already done some of them, but they take time, and I haven't had a lot of that lately. :-) But even some of the newer ones have flaws, it depends on the panoramic and what I've done with them, and how much time I relegated to it. Some are pretty much perfect. Others, not so much.
Here's a panoramic of Mount St. Helens broken down into it's individual components, and a link to the actual panoramic:
The problem with stitching programs:
Stitching programs make assumptions about your photo sequences. They try to compensate
by asking the focal length of your lens and distort the picture,
but they still can't know the exact circumstances of how you took the image sequence. They
also can't compensate for perspective or barrel distortion, and can't color match. And they
tend to cut people in half in crowded scenes.
Here's a link to the actual panoramic.
Doing it yourself:
So I learned how to manually stitch a panoramic in Photoshop, without the aid of a stitching
program. Anyway, I've had more than one person ask, so here's what I do:
Taking a panoramic:
You should use a tripod. (Confession, I never do, unless I'm shooting at night.)
You *must* overlap the images. Generally an overlap of 30-50% is ideal, any more than that is counter productive. But there has to be sufficient overlap to overcome any perspective or barrel distortion. I'll discuss this later.
If you don't use a tripod, try to keep the camera level without any vertical movement between frames. Some cameras, like the Canon G series digicams, has a panoramic helper to line up the panoramic. (Confession, I've never used it.) My Canon G12 actually tells me if I'm not level, so it's less of a problem now. It doesn't matter if the individual pictures are in a vertical or horizontal format, so long as you're consistant.
Joining the panoramic:
Generally, here are the steps I take blending the separate images together.
I use photoshop. It's what I know, and I've been using it since... version 4.5?
So I'm using Photoshop terms (in italics), so translate to your photo editor
accordingly.
Preparation:
Identify which pictures within your picture set are panoramics.
This may sound stupid, but I have actually found panoramic sets
years after I've taken the pictures. They are generally easy to
identify if you take the sequence from left to right, but if you
take a sequence from right to left, it may not be as apparent.
Create a blank sheet, and move all of the images to it in sequence, as individual layers. Warning: I've had very large initial Photoshop documents, some as large as 900MB.
Correct any obvious errors for each individual layer, such as a picture being unlevel or perspective distortion. Don't try to adjust brightness or color balance at this time.
Blending:
1) I usually start from the left to the right, though there are times I'll start in the center and work to the left and right at the same time. Take two of the images that are to be joined, and change the top image's Fill to about 50%. (50% is an approximation, it might have to be more or less than that value.) This will make the top image semi-transparent. Move the top image over the bottom one, and line up the center of the overlap. When you move the top image around, you should find one point where the top image almost matches the bottom image:
3) Continue with the rest of the panoramic, joining each new image to the newly forming panoramic.
4) After your done joining the entire panoramic, you have to go back and start to adjust the brightness and color balance. This is where you *really* need to know how to use your editor. Brightness differences can be compensated using Levels and Brightness/Contrast. Color balance can be adjusted with Color Balance, Hue/Saturation and in extreme cases, replace color. Each of these commands, while similar, has their differences. Experiment, that's all I can tell you. Here's a link to a panoramic of a sunset over the Gulf of Mexico. It took me four years for me to get this close, and as you can see, I still don't have it right.
5) Once the entire panoramic is done and looks consistent, flatten the image, crop, adjust the levels and sharpen as necessary. Once you do that, if you can still see the seam, you have to go back a step and re-balance the individual pictures.
And a bit of advice, save generational copies of the panoramic. I generally save a copy of the raw images before joining, another copy after joining the pics, another copy after color correction, and another copy after cropping the pic, and another final copy after resizing and sharpening the panoramic.
I would also start with two or three image panoramics, and work your way up.
Problems and issues:
There are some issues that need some discussion. Up until now, there's a good chance a
stiching program could have done a decent job. But let's look at some of the things a
stitching program can't deal with.
Physics cannot be denied. Look at this collage. What's the difference between the images on the left, and the images on the right?
The ones on the left has the sun in front of the camera, the ones on the right have the sun to my back. This means if you're shooting a panoramic, the sky color could wash out. Trying to compensate for this is near impossible. The problem is lessened at noon, and is compounded near sunrise and sunset. This panoramic of Main Street demonstrates this problem. This is a panoramic of the Lochsa River that tries to fix the problem. (Note I said 'tries'.)
Perspective and barrel distortion.
The closer you are to the subject of the panoramic, the worse
the perspective distortion will be. For instance, the image on the left shows the distortion,
the picture on the right has been corrected:
It's impossible to stitch a panoramic without correcting for this. Below is probably the most extreme example that actually worked, and the link to the pan. The distortion is pretty bad because of the proximity of the building (I'm almost right in front of it), and the wide angle focal length I was using. This panoramic also demonstrates the ability to come back later and reshoot a bad picture. When I first took the panoramic, the sun was over the buidling (lower right), so we went on the attraction and when I came out, the sun was behind the building. So the first two images we taken 30 minutes after the rest.
Here a portion of one that didn't. But the rest of it looked good enough that I kept it anyway. :-)
(And here's the link to the actual panoramic.) [Update: Since I've written this page,
I went and bent the pic a little. I still need to reshoot the Main Street Panoramics.]
People.
Those darn people. If they'd only stand still...but they never do.
Unfortunately, I can't tell you how to avoid cutting people in half, since the technique seems to change from panoramic to panoramic. This is a portion of a panoramic that does this (and a link to the actual panoramic.) Note that this technique *duplicates* some people (which is why there are a couple of sets of identical twins in the image), but it doesn't look unnatural, like some photo from Back to the Future...
We don't live a flat world. But pictures do. You have seen me advocate Photoshop CS2 or above. That's because they have a new tool called Image Warp. This new tool allows you to virtually warp an image in any way you want.
It's very easy to tell that the top image is from three discreet images. The bottom one, not so much. It takes literally seconds to do what before was extremely difficult. You'll run into this problem anytime there's a straight line (usually a road) in your panoramic.
Hiding seams.
Above I said never to use straight lines. Well, never say never. If you're taking
vistas of National Parks or some other natural place, then you should never use straight lines.
But humans love straight lines. So, if you're doing panoramics of cities or buildings, straight lines can sometimes hide things rather well. (And here's the link to Allen Street in Tombstone.)
This is acutally another panoramic that had severe perspective distortion, so severe, that I had to kinda paste the boardwalk itself back together. But it's a nice 360+ degree panoramic. (And the link to The Boardwalk panoramic.)
I guess the final question is, why? Well, I do have a printer (an Epson Stylus Photo R1800) that takes 4", 8" and 13" glossy photo roll paper, so I can actually print these panoramics at full size. The drivers only allow me to print 40" wide, but you can get around that... Beyond that, I think that the panoramics really do capture more of the grandeur, beauty and presence of the subject at hand; whether a mountain range, or a theme park. And they certainly are different from your normal picture album. I guess it's just a logical extension of photos in the digital age.
Anyway, have fun! That's what it's all about anyway.
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