essential skills: digital photography in available light
- Ensuring the camera is level
Although Photoshop’s Photomerge and other stitching programs are designed to adjust images
that are slightly rotated, it is far better to ensure that all source images are level to start with.
The easiest way to achieve this is by photographing your scene with your camera connected to
a level tripod with a rotating head. If you are out shooting and don’t have a tripod handy, try to
locate a feature in the scene that remains horizontal in all shots and use this as a guide to keep
your camera level when photographing your image sequence. Failing to keep the camera level
will result in a series of steps at the top and bottom of the stitched photos where the pictures are
slightly out of alignment. For the most part these jagged edges can be removed with a simple crop
but sometimes this cropping step will loose important scene detail. - Keep the exposure constant
As the lighting conditions can change dramatically whilst
capturing the sequence of images you need to create a
panorama, it is important that the camera’s exposure be set
manually before commencing the sequence. Leaving the
camera set to auto exposure (Program, Aperture priority or
Shutter speed priority) will result in changes in brightness of
sequential images, especially if you are capturing pictures
throughout a full 360 degree sweep of the scene.
Take readings from both the shadow and highlight areas
in several sections of the environment before selecting an
average exposure setting, or one that preserves important
highlight or shadow detail. Lock this shutter speed and
aperture combination into your camera and use the same
settings for all the source images.
If the scene contains massive changes in brightness this will mean that some parts of the picture
are rendered pure white or pure black (with no details), then you may want to consider capturing
a second sequence using a different set of exposure settings.
Not keeping the camera level when photographing source images will mean jagged or stepped edges in the fi nal
stitched panorama. These edges can be trimmed with the crop tool but in this example that would mean losing
important details in the scene so the only answer is to reconstruct the missing areas using features like Photoshop’s
Clone Stamp and Patch tools.
Set your camera to manual
exposure to ensure consistency
across the sequence of images