Difference between revisions of "Bracketing"

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(pasted stuff from mailing list)
 
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these 8bit images into an 8bit panorama.
 
these 8bit images into an 8bit panorama.
  
* You have to use the same 'exposure' when merging each shot, but you don't know what that needs to be until you have finished and can see the result (not a problem if you use a [[full 16 bit workflow]]).
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* You have to use the same 'exposure' when merging each shot, but you don't know what that needs to be until you have finished and can see the result (less of a problem if you use a [[full 16 bit workflow]]).
  
 
== Contrast blend bracketed panoramas ==
 
== Contrast blend bracketed panoramas ==
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operator to generate 8bit images.  Then stitch these into an 8bit panorama.
 
operator to generate 8bit images.  Then stitch these into an 8bit panorama.
  
* You have to use the same tone mapping settings for each shot, but you don't know what that needs to be until you have finished and can see the result (not a problem with a [[full 16 bit workflow]]).
+
* You have to use the same tone mapping settings for each shot, but you don't know what that needs to be until you have finished and can see the result (less of a problem with a [[full 16 bit workflow]]).
 
* Local tone mapping operators will behave differently for overlapping areas, you need to hope that blending with [[enblend]], [[smartblend]] or [[PTGui]] will fix them.
 
* Local tone mapping operators will behave differently for overlapping areas, you need to hope that blending with [[enblend]], [[smartblend]] or [[PTGui]] will fix them.

Revision as of 16:10, 18 August 2006

Most digital cameras allow taking of bracketed shots, ie. more than one picture of the same scene, but at different exposures.

This can be useful when photographing panoramas.

Panoramic stitching techniques

Simple

Pick the best exposed set of images and discard the rest.

  • This may be good enough, though you lose the ability to use the entire dynamic range in the final panorama.

Contrast blend bracketed shots

Use Contrast Blending to merge each bracketed view, then stitch these 8bit images into an 8bit panorama.

  • You have to use the same 'exposure' when merging each shot, but you don't know what that needs to be until you have finished and can see the result (less of a problem if you use a full 16 bit workflow).

Contrast blend bracketed panoramas

Stitch each exposure step into a complete 8bit panorama, then merge these with Contrast Blending into an 8bit panorama.

  • Running enblend multiple times is slow.
  • Ghosting unless your panoramas are aligned perfectly.

Convert bracketed shots to HDR

Merge each bracketed view into an HDR image, stitch these into an HDR panorama and then reduce to 8bit with tone mapping.

  • Local tone mapping operators produce ugly artefacts in equirectangular panoramas.
  • Currently this workflow is only possible with hugin.

Convert bracketed panoramas to HDR

Stitch each exposure step into a complete 8bit panorama, then merge these into an HDR panorama and reduce to 8bit with tone mapping.

Tone map bracketed shots

Merge each bracketed view into an HDR image, use a tone mapping operator to generate 8bit images. Then stitch these into an 8bit panorama.

  • You have to use the same tone mapping settings for each shot, but you don't know what that needs to be until you have finished and can see the result (less of a problem with a full 16 bit workflow).
  • Local tone mapping operators will behave differently for overlapping areas, you need to hope that blending with enblend, smartblend or PTGui will fix them.