shutter and related camera vibration sources can be significant limiting
factors at the higher resolution levels; Dr. Skudrzyk's Photography for
the Serious Amateur notes that his results for lenses were typically 1/3rd
higher than often reported in other tests, which was largely credited to
using short duration studio flash for exposure, thereby minimizing camera
related vibration (and these tests were on seriously heavy tripod setups).

as jjs noted, tests show some degradation at speeds as fast as 1/250th
See chart at http://medfmt.8k.com/mf/vibration.html

even more shocking, the value of mirror lockup may surprise many
photographers, including many whose current cameras don't offer this once
common feature, see http://medfmt.8k.com/third/mlu.html chart of Pop tests
telephotos gained circa 100% (135mm) to 170%+ (300mm) when used with MLU
on sturdy tripods at speeds around 1/15th to 1/60th second etc. Yeech! ;-)

grins bobm
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* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
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