how to: panorama ???

[dustydirtbiker]

How do you make panoramas?

Ive tried to take a few panoramas before. One sunset landscape, one skyscraper, and a staircase. Both the sunset and skyscraper couldn't stitch (i guess because of the distortion at 18mm). The staircase didn't work well because I was on aperture priority and the shutter speed must have changed for the top photo. I know how to fix the stair problem, but did the other two not stitch because they were at 18mm?

I think I've seen slightly distorted panoramas before...

[Tom]

Yeah, you want to use a longer focal length to eliminate distortion. What focal length determines how big a panorama you are going to do. I've shot some at 100mm and some at 24mm, but 50-70mm seems to be a sweet spot for me.

[Anacott]

One thing most people aren't aware of is that you should shoot your panoramas vertically. This is because how the corners distort on the lens. You will get much better results if you are using 8 photos vertically combining the middle 65% than if you combined 4 horizontally using the middle 65%. Also, change your white balance to something besides auto. That will prevent your sky from changing colors as you pan across. Also, shoot in manual mode with the same speed/aperture for each shot.

[gtakacs]

Originally Posted by Thomas Campbell

Yeah, you want to use a longer focal length to eliminate distortion

Originally Posted by Anacott

One thing most people aren't aware of is that you should shoot your panoramas vertically. This is because how the corners distort on the lens.

Both of these statements are incorrect. I personally shoot all my 360x180 VR panoramas with a 10.5mm fisheye lense which has plenty of distortion (like this one: http://www.gregtakacs.com/portfolio/vr-panoramas/vr015)

The trick is to
1) Use the right tripod head to ensure rotation around the entrance pupil (often wrongfully called the nodal point). For wide angle full spherical panoramas shooting from a spherical head with the entrance pupil in the point of rotation will guarantee that you will experience no parallax problems. If you shoot wide landscape panoramas where everything is in the distance (such as this one: http://www.gregtakacs.com/portfolio/vr-panoramas/vr016 ) the entrance pupil being in the same spot is not as critical.

2) Use the right software. Using a panorama stitching software such as PTGui or Hugin will distort and align your images properly to stitch right.

3) Use the right projection. If you shoot panoramas to increase pixel count or to replace a 12mm lens with an 18mm shot twice in the vertical you can still use rectilinear projection. For anything wider than 100-120 degree FOV you have to start thinking about other projections such as cylindrical or equirectangular (spherical) or there are some new, mixed projections such as the panini (you'd think I'm making stuff up, but I'm not) projection.


The advice about shooting with the camera in the vertical position is still a good advice though (as long as you're shooting a horizontal panorama, not a vertical view of a skyscraper). The reason is that that way you maximize your vertical FOV and you can shoot as many pictures horizontally as you need to get the whole image. Then again you can get into multi row panoramas and hold your camera any which way you like...

[Anacott]

Actually both statements are correct. Most people don't want crazy distortion in their images like you've posted. If you want a skyline or any view you should should it vertically. Ultra wide will give you a lot of distortion and stitching programs have a problems with that.

[Tom]

Sorry, but my statement is correct.

Can you shoot with a Fish? Yes. Is it the easiest method for a beginner? No.

When the guy is saying he is having a problem with distortion at 18mm, going up to a longer FL is the easy and correct solution.

Another correct statement would be to shoot it so your shadow is not in the panorama for better results.

[gtakacs]

Originally Posted by Anacott

Actually both statements are correct. Most people don't want crazy distortion in their images like you've posted. If you want a skyline or any view you should should it vertically. Ultra wide will give you a lot of distortion and stitching programs have a problems with that.

I'm going to stand my ground on this one. What you are talking about is shooting a narrow FOV panorama with a zoom lens to maximize image resolution instead of shooting with a wider angle lens and cropping out the middle. But then the advice goes on and says shoot vertical then crop out the middle!

Shooting vertical with a 50mm lens only to crop out the middle part and stitch them together makes no sense. You might as well shoot horizontal and stitch fewer images. Or use a longer zoom and maximize your pixel count and resolution.

The only time rectilinear distortion towards the edges become a problem is when you use something like Photoshop to stitch your images together instead of a dedicated software such as PTGui that deals with the distortion and projection accordingly instead of doing it a ho-hum "we'll try to merge these pictures in a real assinine ignoring individual projections within the image way" that Photoshop does.

As for crazy distortion in the images I have posted. I'm not sure if you have noticed that those images actually show a full 360x180 view and are displayed in an equirectangular projection. The Grand Canyon panorama ( http://www.gregtakacs.com/portfolio/vr-panoramas/vr016) shows a 180 degree horizontal FOV on a cylindrical projection. These projections ,equirectangular (spherical) and cylindrical can not keep straight lines straight in a 2 dimensional plane.

What your advice was is "crop the middle so we can get around the limitations of stitching rectilinear projections into a mush of rectilinear projections in Photoshop while ignoring proper projections and hope to get away with it".

gtakacs added 17 Minutes and 46 Seconds later...Double Post Merged Below

Originally Posted by Thomas Campbell

When the guy is saying he is having a problem with distortion at 18mm, going up to a longer FL is the easy and correct solution.

The easy and correct solution is to use the right software to stitch the images and in that case it doesn't have issues with distortion.

I don't know what software the original poster is using but if he is having issues with distortion it's certainly not a proper panorama stitching software.

However I do know that the original poster was trying to stitch 18mm images together indicating that they were interested in wide angle panoramas, not cityscapes from a distance.

[Anacott]

Welcome to the forum Gtacks. Nice to have an argumentative person on an advice blog. As I'm sure you know, since your a professional, there is never one way to shoot something. If we only wanted one person's viewpoint then the blog would limit replies to initial posts to 1. No one said your comments were invalid, we were just giving our opinions. My points are also stated by Scott Kelby (maybe you've heard of him):

http://www.peachpit.com/articles/article.aspx?p=1025307

Dustydirtbiker, you now have several posts to learn from and should be able to shoot many different types of panos. Good luck!

[gtakacs]

Originally Posted by Anacott

Welcome to the forum Gtacks. Nice to have an argumentative person on an advice blog. As I'm sure you know, since your a professional, there is never one way to shoot something.

Thanks for the warm welcome, Anacott (I hope I spelled that right), same to you! I am sure you are a professional yourself also, maybe not as experienced in panorama shooting as me. I am an engineer by profession so it is my daily routine to substantiate claims with arguments, especially when they are meant to refute incorrect information.

If we only wanted one person's viewpoint then the blog would limit replies to initial posts to 1. No one said your comments were invalid, we were just giving our opinions.

I like that statement about limiting responses to 1, it's funny. I guess "Sorry, but my statement is correct." and "Actually both statements are correct." were not posted in disagreement. I only posted my initial, 3rd on the list, reaction after seeing two, blatantly wrong assumptions about how to shoot panoramas.

My points are also stated by Scott Kelby (maybe you've heard of him):

http://www.peachpit.com/articles/article.aspx?p=1025307

Just because someone with authority (?) states something does not make it right. Also just because a lot of people say something it does not make it right (we should all eat poop, a billion flies can't be wrong!). That very article you linked in starts with this on page 3 "Building the Panorama in Photoshop". Scott Kelby lost all credibility in my eyes with that single statement in terms of panorama advice.

If you primarily shoot nature or straight lines and converging verticals are not important to you, by all means use Photoshop to fudge your pictures together. But if you care even the slightest bit about panoramas I highly recommend investing in some specialized panorama software, both time and money wise.

Maybe you should go out and shoot some panoramas yourself and stitch them with a panorama stitching application instead of regurgitating someone's, should I mention incorrect, information.

[Anacott]

Your right. After looking at your panos I've decided to sell all my equipment. I'll never be this good. I'll pass the info on to Scott Kelby that he's wrong too. Good luck.

[Tom]

However I do know that the original poster was trying to stitch 18mm images together indicating that they were interested in wide angle panoramas, not cityscapes from a distance.

And I do know that I have no problem making a wide angle panorama from a series of 70mm shots.

I am sure you are a professional yourself also, maybe not as experienced in panorama shooting as me. I am an engineer by profession so it is my daily routine to substantiate claims with arguments, especially when they are meant to refute incorrect information.

Ahhh. So you aren't a professional photographer. You are a engineer with a camera. And a GWC that probably hasn't had as much experience shooting panoramas as me.

I only posted my initial, 3rd on the list, reaction after seeing two, blatantly wrong assumptions about how to shoot panoramas.

Sorry, but the statements made are not incorrect.

Just because someone with authority (?) states something does not make it right.

And here you are, a hobbyist with no authority, trying to say only you are right and everyone else is wrong. Take a look in the mirror.

If you primarily shoot nature or straight lines and converging verticals are not important to you, by all means use Photoshop to fudge your pictures together. But if you care even the slightest bit about panoramas I highly recommend investing in some specialized panorama software, both time and money wise.

And many people do not like the distorted look that your panoramas have. I bet a lot of people laughed to themselves when they saw your hulking shadow in a completed panorama you shot.

There is more than one way to skin a cat. You should learn that a wide lens on a tripod isn't the only way to shoot a panorama just like 100 F16 1/250 isn't the only way to shoot in sunlight.

Reading some Dale Carnegie wouldn't hurt, either.

[AndrewCCM]

Appears that both are fairly new to the forum.

Let's not bicker. This is one forum (not a blog) that is somewhat immune from such things (as a whole).

I am as guilty as anyone for being a smart-arse here. But I personally found some useful advice from all the posts in this thread.

Enjoy TPF. Lots of fun, creative, helpful and polite folks here.

[venchka]

Whoa! Different strokes for different folks.

Not everybody wants or needs 360-180 VR Widgets.

If I may relate my extremely limited experience in this area.

A longer lens turned vertically does indeed work well. I can tell you for a fact that a very wide lens, 88° field of view, oriented horizontally and 3 overlapping frames does not work. Oh, I got the images stitched, but the results were awful. Also, working close to the subject isn't ideal either.

Not sure I can explain this, but I'll try. Full frame advice. Apply the math for a crop body.

Suppose you want the vertical coverage of a 35mm lens and several times the horizontal coverage. First instinct is to make 3-5 horizontal shots with the 35mm lens. Wrong. Ok, wrong is a bit harsh. Not as good as it could be, ok? I'm pretty sure that the wide side of a 50mm field of view is close to or equal that of the vertical field of the 35mm lens. So, use a 50mm lens turned vertical to get the height of the image and then make a bunch of overlapping frames. Easily double the number you would have made with the 35mm turned horizontal. Oh yea, get as far away from the subject as possible. For normal landscapes, this is easy. if there are things in the foreground close to the camera, you might want to avoid them. Or shoot two sets. One with, one without the close objects. You might get lucky and the foregorund stuff makes for a great picture.

In summary: A few frames very wide and subjects very close don't work. More frames, less wide and subjects farther away work.

As for all the fancy high priced gizmos for making panoramas: Not too sure about those. I don't think you need them for landscapes.

By the way, none of this new. Folks were making panorama photos in the 19th century.

Don't forget: You can make multiple rows. A 3-way head works vey well for multiple exposures.

Greg Miller had this to say in another forum...

Originally Posted by Greg Miller

Photoshop CS3's photomerge function is very capable (I could not say that for earlier version) for stitching. If you have CS3 it is free and it is simple to use and understand.

For landscapes and nature, I find parallax to be pretty much a non-factor. All of the panoramas in the panorama section of my web site were taken with a normal setup (just a tripod with a normal ball head) and no effort spent finding nodal points of the lens. The images were 100% assembled manually in Photoshop or by using photomerge. (yes, I have done multi row, multi column panos manually).

I also have a photo book being published later this year that is primarily panoramas. None of those images required any special gear either. The only extra piece of gear I use is a leveling head. This is not a requirement but certainly makes things easier.

If I really need to worry about parallax, I use a simple Wimberly plate that is long and has an Arca-Swiss clamp on it. This plate allows me to move the camera/lens forward and backward within my primarily clamp. BY looking thought the viewfinder while panning it is pretty easy to find the nodal point where parallax is eliminated.

You might enjoy Greg's work...

http://www.gregmillerphotography.com/

ps: I don't know anything and I was able to make Hugin stitch some pictures together. It's the best kind of software: FREE!

Enjoy!

[gtakacs]

Originally Posted by Thomas Campbell

And I do know that I have no problem making a wide angle panorama from a series of 70mm shots.

You most certainly can make a wide angle panorama with a 70mm lens.

A 70mm lens has a horizontal FOV of 18.15 degrees on a 20D and 23.1 degrees on a 1D Mark II (http://www.sweeting.org/mark/lenses/canon.php).

Now let's define wide angle panorama. For me, to consider it wide angle it would have to be 90+ degrees horizontal FOV. So if You shoot the 70mm lens in the vertical position, to obtain 90 degrees FOV on the horizontal you would shoot about 11 vertical shots (with 1/3 overlap on crop sensor camera) to cover the 90 degree FOV. And you would end up with an image that has 18 degrees FOV on the vertical and 90 degrees on the horizontal.

On a equirectangular projection that means it's an image that has a ratio of 5:1 width and height. The question is, do you need this kind of resolution and does it make sense to increase your workflow and file storage requirement and processing time to stitching and storing 11 images when you could have taken 3 images at 20mm, stitch them, crop out the middle to get the same vertical FOV, and accomplished the same thing by using a decent panorama stitching application and chose a projection that gives you a pleasing distortion? Throw in HDR at 5 stops at 2EV steps and you're looking at 55 images vs 15. That's a lot of bits and required horsepower to process something that will never be made into a poster on the side of a bus (your stuff might get made into a poster on the side of a bus, I don't know).

Note that I said pleasing distortion, not no distortion. There is going to be distortion, it's just what kind of distortion are you comfortable with for the particular subject is what matters.

For a great primer on distortion of different projections I recommend looking at this link: http://www.tawbaware.com/projections.htm Unlike Scott Kelby, this guy knows what he is talking about when it comes to panorama stitching whether it's with a fisheye or a 200mm for a gigapixel panorama.

Ahhh. So you aren't a professional photographer. You are a engineer with a camera. And a GWC that probably hasn't had as much experience shooting panoramas as me.

Feel free to visit my portfolio and draw your conclusions about my professionalism and experience with panorama photography.

And here you are, a hobbyist with no authority, trying to say only you are right and everyone else is wrong. Take a look in the mirror.

I am not saying everyone else is wrong. However I am still 100% sure that neither of the two other active participants in this thread, nor Scott Kelby has any clue about the math behind different projections and distortions. "If it looks good, it must be good" is the mantra. And for the most part in photography it certainly stands true, photography being and art form and all. However, when it comes to architectural photography or anything with a straight line in it, it never hurts to understand the limitations and workarounds to get the optimal image. I resent the "no authority" comment. Who made you king of the hill?

And many people do not like the distorted look that your panoramas have. I bet a lot of people laughed to themselves when they saw your hulking shadow in a completed panorama you shot.

I challenge you to show me a 360x180 degree panorama with no visible distortions (hint, it cannot be done). If you had clicked the VR Panorama button under each panorama you would have seen how they look when they are displayed as a limited VOF rectilinear image (hint: they look just like regular rectilinear photographs even though they were taken with a fisheye lens).

There is more than one way to skin a cat. You should learn that a wide lens on a tripod isn't the only way to shoot a panorama just like 100 F16 1/250 isn't the only way to shoot in sunlight.

There is no disagreement on my part here. But when the original poster clearly tries to shoot and stitch 18mm images together to gain an even wider FOV, advising them to shoot with a longer zoom is not the solution. It will not solve their problem, which is simply the fact that they have used some software that was not meant to stitch together panoramas from rectilinear images and correct for distortion then apply a new projection to the stitched result (actually, panorama software applies the final projection to the individual images first, then stitches them together, but that's just a minor detail).

[jeffkohn]

I do think it's worth clarifying whether one is trying to shoot spherical VR panoramas or more traditional photographs that happen to have a wide aspect ratio, since the techniques vary a bit and what works best for one isn't necessarily best for the other. Spherical VR panos require more precision, but for a simple 3:1 pano with a 90-degree FOV you don't have to be quite as careful (although precision can still be helpful).

The choice of whether to shoot horizontal or vertical doesn't really have anything to do with distortion. The advantage of shooting vertical is that it typically means taking more shots, so you end up with more resolution in the final image. But you can can avoid geometric distortion (and light falloff) in the corners even while shooting horizontally; just make sure you have plenty of overlap.

There are actually two kinds of distortion. The first is geometric distortion. This has nothing to do with perspective or field of view, it's actually a property of a specific lens. Many if not most telephoto lenses have at least some amount of pincushion. while wideangles usually have some barrel distortion. Different lenses at the same focal length can have varying amounts of distortion, so choosing a lens with minimal distortion can be helpful when shooting panos. Stitcher software cannot automatically correct for this type of distortion unless they have a database of lens-specific corrections to use, so it's best to either avoid geometric distortion in the first place by using a low-distortion lens with plenty of overlap between shots, or to remove the distortion using lens-specific corrections (PTLens is one example of a program that can do this) before stitching.

The second type of distortion is often referred to as perspective distortion, and I assume this is what Greg is calling rectilnear distortion. This is what causes converging verticals, as well as causing objects close to the edge of the frame look stretched out. This is a matter of perspective and field of view, and it doesn't really matter what focal length you use. What matters is the total field of view in the stitched pano, as well your choice of projection. The wider the field of view in the final pano, the more important it becomes to choose the right projection. You don't want to use a rectlinear projection for really wide FOV's. Greg mentioned 120 degrees, I'd actually recommend that for anything over about 90 degrees you might want to try something other than rectilnear; for landscape and nature photography, it's a subjective choice and you may find that which projection looks best to you depends on the scene in question.

One impact that your choice of focal length does have is that when you use a really wide lens, the pano software has to do more warping and interpolation to get the images to stich together. This can result in lower quality in the final result, especially if you weren't careful to rotate the lens exactly over the entrance pupil. So using a longer lens with more shots might give you better overall image quality than using a wider lens, but it doesn't really change the amount of perspective distortion in the final image.

A general rule of thumb is that the wider the focal length, the more overlap you want to use between frames. For instance, at normal-to-telephoto lenghts I might only use 25% overlap. But if I'm shooting with my super-wide I'll increase the overlap to as much 40-50%, because the more overlapping you do the less interpolation the stitching software has to do.