Re: Digital Image Stitching II

On Wed, 31 Oct 2007 13:57:54 -0000, "ChrisM" <chris_mayersblue@xxxxxxxxxxxxxx>
wrote:

With exposure, hopefully, on a
distant subject, and as long as the light doesn't change (sun goes behind a
cloud or something) the auto exposure should stay consistant(?).

No, it will not stay consistent on auto-exposure. Anything that changes the view
will change the exposure and white-balance settings. It may not be apparent to
your eye, or even when reviewing them in the camera, but rest assured that when
you go to stitch them you will have glaring exposure and white-balance
differences between the panorama panels that might be impossible to blend
seamlessly.

If your camera does not have a way to manually lock in exposure and
white-balance settings, then you can use a clunky work-around that I discovered
about 8 years ago using my first digicam, then posted this method to the
internet for others to learn from.

Select an area of your panorama that has some average light values, the
mid-range intensity and color-values of your full panorama. Example, if taking
an image of a sunset, select an area halfway between the reds of the sun and the
dark-blues of the sky. Take that shot. REMEMBER THAT SCENE. Now frame that shot
again, half-press the shutter to lock in its exposure and white-balance setting.
Pan over to your next pano-panel, fully depress the shutter to take that new
image. Return to your first reference scene. Half-press to lock in it's exposure
and white-balance again. Pan to the 3rd panel you want. Repeat as many times as
you need.

.

Relevant Pages

  • Re: Availability of WA lenses
    ... The last few cameras I've had have required that a button be held pressed, ... now has a proper lock. ... Locking exposure, white-balance, and focus with a half-press from one ... It became a popular pano topic because this technique ...
    (rec.photo.digital.slr-systems)
  • Insufficiency of vitamin D common in elderly Spanish population
    ... BACKGROUND AND OBJECTIVE: To identify the factors related to hypovitaminosis D in the population over 64 years of age without known risk factors of hypovitaminosis D. SUBJECTS AND METHOD: It was a cross-sectional population study in individuals over 64 year-old attending basic healthcare areas in our hospital's area of reference. ... A survey was conducted to assess various items (functional capacity, exposure to sun, walks, eating habits). ... Participants with deficiency scored lower on the Barthel index, had a higher mean age, lived in flats, had less exposure to sun, and used to walk less in sun-hours. ...
    (sci.med.nutrition)
  • Re: More on Canon Rebel XT noise at high ISO - 2 main new data points
    ... explain the circumstance where you need to take an exposure lock the English used to describe operation of it is clear, concise, and has no evidence of the poor 'literal' translation that I have seen in some instructions. ... the instruction manual for operating the camera is no more a tuition in photography with it than the instruction manual for a motor car is driving lessons. ... Besides you were not exactly reticent at attacking anyone who did not accept that you were right and Canon were wrong. ...
    (rec.photo.digital.slr-systems)
  • Re: Radiation from Wireless LAN vs Bluetooth PAN
    ... The sun belches most of its ... If I compare this to a typical 35mw wi-fi radio, ... As for comparing wireless exposure with a known cancer cause, ...
    (alt.internet.wireless)
  • Re: More on Canon Rebel XT noise at high ISO - 2 main new data points
    ... > explain the circumstance where you need to take an exposure ... > that because Canon 'must be right' ... > exposure) lock obtains and locks the correct flash exposure ... "My enemy's enemy is my friend, and my enemy's friend is my ...
    (rec.photo.digital.slr-systems)