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> Suppose you wish to covertly record the location of a stash of gold
> buried in the Sahara desert (say). Could you take a casual looking photo
> which would convey enough information to make a fix within a few nm of
> where the photo was taken?

If camera has a gps in it, megadata would have the fix.

Wide angle and *a* photo (one photo, as per the stated problem)?  As
list "camera as a sextant" master Greg has pointed out in the past the
pixel counting works best (or easiest at least) with a telephoto using
the center of the lens. A wide angle would be, I suspect, a bear to
calibrate.

Ken G in the past claimed he had a drawer full of images of the sun
where he could tell the elevation of the sun by the amount of squish
caused my refraction as it neared the horizon. At last mention he has
yet to write his book which would include that method. Being desert,
abnormal refraction might be major hurdle as well.

At this point I'm still scratching my head. Any method I can imagine
with one image has major drawbacks, including the need to record time
and date either in the megadata or by hand. Is an image with a watch and
or calender included a "casual" photo? And just how does one get the
depth of field to have both a body at infinity and the watch in focus
short of the Lytro light-field camera?

I haven't thought it through, but perhaps latitude through elevation of
a body via pixel counting or squish and a time sight for longitude?

Bill B.

   

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