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I am fortunate to have access to the rooftops of several highrise buildings in my city, and am tasked with taking some panoramic photographs of the city for my firm, ideally 360-degree views.

This is not something I will be able to easily repeat, so I would like to do as much preparation as possible to get good shots. I have a couple questions:

  • What is the best time of day to do this? Midday, when the sun won't be in any shot?
  • Do I take many shots with a long focal length, or use a wide lens and take as few as possible, to make stitching easier?
  • I know it is best to only rotate the camera, not move it, when doing panoramas. For some buildings this may be possible, but I expect that I will have to walk around a bit to get complete coverage on a lot of them. Is there any way I can mitigate this problem? Would I be better off doing two 180-degree panoramas from opposite corners instead of trying to get one all the way around?

Anything else I should know about?

EDIT: Lots of good suggestions, thanks. I hadn't even thought about exposure settings, and it seems that there is a mix of "better to use manual so all shots are the same" and "better to use auto so that you get better dynamic range from light to dark spots." Anyone had good or bad results with one way or the other?

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  • \$\begingroup\$ This isn't really an answer, but Google around for some of the video's showing when the SmugMug guys decide to do one of their pano's - its quite impressive. \$\endgroup\$
    – rfusca
    May 4, 2011 at 13:31
  • \$\begingroup\$ See warszawa360.pl/about.html for how to do it from one spot. The camera is basically mounted on a rotating pole so the camera can see 360-degrees around. \$\endgroup\$
    – Itai
    May 4, 2011 at 15:51
  • \$\begingroup\$ Not only is the time of day important (sunrise or sunset) but also the season. Spring and fall have more pleasing light, fall being my personal preference. Summer is too harsh. \$\endgroup\$ May 4, 2011 at 19:12

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I'm going to need to answer these in the reverse order and I'm going to assue you're probably going to be blowing these up quite large.

  • If you're going to move the camera several feet to get the shots you want, you're going to get some sort mismatch when you stitch. If you're then going to blow the pictures up large, it's very likely going to look some degree of bad along a seam. How to mitigate this is really to either just do smaller pano's or find a 360 degree spot. There's alot of things that will determine how bad or not bad this will be - largely based on the particular field of view you have, but make sure to have as much overlap there as possible.

  • Choosing your focal length is probably your biggest decision as it drives a few other things. The higher you go, the more impressive its going to be. When you've got a city pano and the viewer realizes they can see the guy in the office building staring out two streets away, its a neat feeling. BUT, it comes at a cost. Its significantly harder to shoot and takes much longer - which means your light can change a lot over your total shoot.

  • If time isn't a factor and you can spread it out over several days to do a high focal length shoot at sunrise or sunset - its going to be much more impressive than a few wide angle midday shots. The light at sunrise and sunset is just much better. If you can isolate the sun in a single frame, it will alleviate some of the problems, get it when its behind a building perhaps. Or you could plan several shoots to combine together at twilight, just after the sun has gone done.

You should definitely be setting manual mode, and if you don't have a good tripod/head, consider renting some decent gear, it will make your life easier.

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Time of day will depend on what kind of shot you want. If you just want a 'record' shot of the view, then midday will be fine. If you want something more artistic, sunrise or sunset would be better.

The wider the angle you use when taking the shots, the more distorted the panorama will be when you stitch it. However, most stitching software these days is fairly good at correcting this kind of thing. Ultimately the angle will be determined by how much you want in your shot.

I would say for those buildings where you can't just stand in the middle and rotate the camera, taking the shots in sets of 4, one quarter of the view from each corner, is probably best. The important thing is to make sure you have good overlaps in each shot so the stitching software has plenty to work with.

The other important point is to put your camera in Manual mode so the exposure remains the same throughout the pano - if you have it any auto mode (or Av/AP Sv/SP) the camera will adjust and you will get 'banding'.

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  • \$\begingroup\$ Along the same lines, the color balance should also be set manually, especially if you're shooting JPEG (as opposed to raw). \$\endgroup\$
    – coneslayer
    May 4, 2011 at 13:40
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    \$\begingroup\$ I used to subscribe to the "use manual exposure for panoramas" view, but that was back when I was assembling them manually. Now the automated panorama tools are really good at seamlessly blending colour and exposure changes I just use auto-exposure and shoot lots of overlap and let the software deal with it. An advantage of this approach is you don't run out of dynamic range as easily if your pano is light on one side and dark on the other... \$\endgroup\$
    – Matt Grum
    May 4, 2011 at 14:13
  • \$\begingroup\$ Interesting. I'm still using CS2 - forget about auto color correction there. I understand the newer versions are light years ahead though. \$\endgroup\$ May 4, 2011 at 14:43
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You are right in that the best practice is to rotate the camera w/o translating its position (for the kind of photo you are looking for. There are certainly occasions where pure translation is preferred). However, to make it as precise as possible, you need to rotate it around the lens' nodal point. There is one point around which objects in different depths will keep their relative position once the lens is rotated. It is situated inside the length of your camera+lens, so there is not so much to guess. You can test where this point is for your lens (at a specific focal length) by placing it on the table with a few objects in front (say, standing batteries) one partially occluding the other. Then try rotating along several points and take shots. Where the image of the object does not change, this is the nodal point.

Usually, the problem with implementing that for panos is that mounted on a tripod, you don't have the luxury of sliding the camera back and forth on the head. If this proves to be a real issue for your situation, you can manufacture a DIY adapter for you tripod head that shifts the screw position to the nodal point.

EDIT: Found this video that nicely explains the settings.

EDIT 2: From this answer, it appears that the critical point is the "effective entrance pupil", rather than the "nodal point".

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