Re: Perseids, After Hours (1/30 rule)

[P3D Dr. George A. Themelis <fj834@xxxxxxxxxxxxxxxxxxxxx>]

Reply to message from erker@xxxxxxxxxxxxxx of Thu, 14 Aug

>  FYI last year I shot 3d fireworks with an 8 foot
>separation. The fireworks were about 750 ft away
>judging by speed of sound. I got one good shot
>with depth. Not a lot but enjoyably 3d.
>
>  This year I was closer (est 600 ft). and
>shot more film. I got several excellent shots
>with lots of depth. I doubt that they are
>anywhere near the maximum allowable on film
>deviation (2.7 mm for medium format) but
>"it don't matter if they look good".

When shooting fireworks in the dark sky as the only background you need
more separation than 1/30 because you are trying to separate the fireworks
from themselves and not from the distant background.  The 1/30 rule will
give you the appropriate on-film deviation between your subject and the 
background at infinity.  In the case of fireworks in a dark sky there is
no infinity background. 

-- George Themelis


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