Photography Guidelines

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For panoramic images, first you have to take the photos before you can stitch them together. Here are a few guidelines when taking the photos.

Essential Guidelines

  • Rotate camera around non-parallax point

The non-parallax point inside your lense is where you see the aperture when you look into the camera lense. Rotating the camera around this point avoids parallax error. Correcting this error is outside the scope of stitching software (although the software can fudge to make the effects less visible).

  • Take photos with about 50% overlap

This is for the processing software, most importantly to perform the exposure and vignetting correction. For aligning purpose only, some 20-30% overlap would be sufficient. If you use >50% overlap, your photo series is still usable if one photo in between is spoiled (it happens).

  • Take account of moving objects

Photos are taken at different time. Make sure that in the photo overlap there is an area which has not changed, so either you or the software can place the seam there. With moving objects, clouds or walking persons, try to rotate against the flow in order to avoid duplication.

  • Do NOT use the camera panoramic mode

Usually the camera sets the exposure with the first photo, hence you risk to have several photos with blown highlights. These modes typically give you little control over a number of camera features you want to control. For example, you may want to expose "to the right" or set the distance manually.

Useful Guidelines

  • Use a tripod, possibly with panorama head, or rest your camera on a firm object.

This is again about the non-parallax point. But for non-indoor photography carefully taken handheld photos can be perfectly stitchable.

  • Cover a wider range

For a cylindrical panoramic projection (less than 360deg), cover a wider horizontal range than you plan for the panoramic image, as the barrel shape projection shapes tend to limit the vertical field-of-view in the corners.

  • Set the focus to manual

During a photo series you may point your camera in a direction where there are no features for the camera to focus on. Usually the default distance the camera chooses is not what you want.

  • Use fixed aperture

Vignetting correcting varies slightly with aperture, so one vignetting correction setting can be used. And if your lense contains dust spots (it happens), one needs only one dustmap or flatfield for dust removal. If your camera is dust-prone, take a photo of clear sky - this can be processed into a flatfield.

no longer necessary

Some things that were necessary in the distant past but are no longer:

  1. avoid rolling the camera (software can accomodate that)
  2. use special camera panorama mode
    1. get precise overlap in the camera display
    2. take sequence at fixed exposure and white balance