[LargeFormat] Shutterless lens usage

[Jim Brick]

At 08:34 AM 10/18/2003 +0800, it was written:

>The main problems are jogging the whole setup when you take the cap
>off -


With a multi-second exposure, a small wiggle when removing the cap is of no 
consequence. It would be 10% or less of the exposure so the "blurriness" 
from a small shake would not record.

Look at it another way. If you have a 5 second exposure and you 
inadvertently gave it a 1/4 second exposure, after processing, what would 
the image look like? There would be no image. Artifacts that make up such a 
small portion of the whole exposure are rendered invisible.

This is how they make photographs of busy downtown streets look empty. Make 
many many tiny exposures (1/250) over a period of hours onto the same sheet 
of film, accumulating perhaps the equivalent of a few seconds of exposure 
(plus reciprocity.) The buildings and streets that are permanent are in the 
pictures but cars and people, who move around, come and go, etc, don't get 
recorded.

Jim