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Tuesday, December 18, 2012

Extending Format

These techniques are for much more than panoramas

This Article Features Photo Zoom

4) The layer stack generated

Make exposures with the opposite orientation as the final image orientation. If you're making a horizontal composition, shoot with a vertical camera orientation; if you're making a vertical composition, shoot with a horizontal camera orientation. This does two things. One, it increases the number of frames, and thus, vanishing points, reducing the tendency for the required perspective correction to produce distortion artifacts. Two, it increases resolution, a tendency that becomes compounded with each added pass in multi-column or multi-row exposure sequences.

Once focus is set, turn off auto-focus during the bracketing sequence. Unwanted shifts in focus may ruin an exposure sequence. For this same reason, consider shooting all exposures in a single sequence at the same aperture setting, as significant variances in depth of field between frames may be challenging to merge convincingly.

Consider using manual exposure. While software can convincingly blend exposures with significantly varying exposures, if brightness across a scene remains fairly constant, keeping the same exposure settings between different shots can aid the blending process. (The same is true for white balance, which can be set either during exposure or during RAW processing.) On the other hand, if brightness varies dramatically, bear in mind that simultaneous HDR exposure bracketing isn't out of the question; it just increases the number of exposures needed.


Stitching & Merging
The processing of merging separate exposures is reasonably straight-forward. In Bridge, select the files you wish to include in a photo merge and then go to Tools > Photoshop > Photomerge. Alternately, in Lightroom, go to Photo > Edit In > Merge To Panorama In Photoshop. Whether you start in Bridge or Lightroom, Photoshop will do the merging. (Beside Photoshop, there are other photo-merging software options, such as PTgui, which offer alternative solutions necessary only for the most challenging jobs such as precise architectural convergence.)