Level? I don't need to be level!
|flash shoe spirit level|
Your tripod probably has a spirit level in it, so does your panoramic head, and maybe you bought yourself that really useful camera flash hot shoe spirit level. You may also have a leveller which fits between the tripod and the panoramic head and allows you to finely control whether the base for the panoramic head is level. You may be thinking to yourself "is this all really necessary?". The simple answer is "no", but it's worth explaining when it is important and why.
Why is it a good idea to be level?
Generally speaking, if you are shooting a panorama you are either shooting:
- a cylindrical panorama where the camera is supposed to be parallel with the horizon so in the finished stitched image the horizon is a straight line left to right through the photos
- a cylindrical panorama in which you deliberately want the horizon to be distorted into a wave for dramatic effect when the image is printed
- a spherical panorama in which you can look in all directions including straight up and straight down
In all these situations you need to be sure that when you assemble your equipment, that you've got everything right. Is the camera attached to the panoramic head correctly, not off-centre in any way? Is the tripod level but the panoramic head is not - perhaps the two are not attached correctly? I am pointing out here that using the spirit levels you have is useful for ensuring your shoot is successful, even if you are not actually level.
Only the first of the above shoots requires that you make sure all your equipment including camera is level with the horizon. In the second situation you need to be sure your equipment is setup correctly (for which a level is useful) but you are deliberately going to shoot off-level. And as for the spherical panorama, well, you can re-align the horizon afterwards (see further below).
Getting the level wrong
The following images are simulated and show the kind of problems you might encounter if you shoot a cylindrical panorama off-level when you intend a level panorama. It can be much worse than this, such as if you shoot handheld and your first and last images are misaligned (perhaps you accidentally pitched the camera downwards as you panned around?).
|Woodland scene shot without maintaining good level (simulated)|
|Same picture, showing how it can be cropped|
|Same picture after cropping (black area shows how much has been lost)|
Here's a checklist for getting your equipment absolutely level:
- Tripod. Position your tripod and check it is level using its spirit level if it has one, or a small additional spirit level such as a camera flash hot shoe one (photo above). Make sure the tripod is stable and that all the legs and the centre column are locked firmly, as appropriate.
- Leveller, if you have one. Using its spirit level and/or a separate hand-held one, adjust it to get the top surface level.
- Panoramic head, if you have one. There's a separate guide to using a panoramic head which may be useful. Check the panoramic head is level and that adding the weight of the panoramic head to the tripod hasn't changed anything. Rotate the head around as if a panorama was being shot, and check that it remains level all the way around.
- If you are using a spherical panoramic head, adjust the swing arm to be horizontal and check it is level before you add the camera. Now when you add the camera and you check the camera is also level, you then know the camera is perfectly aligned on the swing arm.
- Camera. If your camera has a flash hot shoe, put the spirit level into the hot shoe to make sure that when you attach it to the panoramic head (or tripod if you are not using a panoramic head) that it is level, pointing at the horizon. If your camera doesn't have a flash hot shoe or if you don't have a photographic spirit level, adjust the pitch of the camera by placing the spirit level that you have on a flat surface of the camera, or on the lens barrel.
- Check: Rotate the camera round as if you are shooting the pictures and make sure that the camera remains level. If it does not you may need to adjust the position of the camera, the leveller or panoramic head (if any) or the tripod.
Spherical panoramas: I don't need to be level!
If you are shooting a full spherical panorama, you do not need to be level because you can adjust the horizon afterwards in software. Both PTGui (as well as PTAssembler, PTMac etc) and RealViz Stitcher allow you to easily adjust the horizon. This means that as long as your equipment is correctly assembled together, you do not need to check levels, which can save you quite a bit of time. And if you do not need to check levels, you could avoid the expense (weight, bulk etc) of a leveller.
- RealViz Stitcher horizon alignment tutorial coming soon
- PTGui horizon alignment tutorial coming soon