Luminous Landscape Forum

Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: Mike W on December 30, 2007, 07:07:51 am

Title: IS lenses + long exposures
Post by: Mike W on December 30, 2007, 07:07:51 am

Hi folks,

I'm kinda new to the whole Image Stabilisation-thing, mostly because I shoot medium format film.
Lately I'm shooting landscape at night, long exposures with a Canon 5D, mirror up, cable release and tripod.

I don't have a need for IS for most of my work, and also no access to them.

I wonder however if IS stays active for the entire duration of the exposure? This would be useful to negate effects from e.g. a passing train, traffic or a single gust of wind.

thanks

Mike

Title: IS lenses + long exposures
Post by: Jonathan Wienke on December 30, 2007, 07:57:59 am

IS is active during the entire exposure.

IS does nothing to reduce subject movement.

For long exposures, (>1 second) IS is not helpful because it "drifts" slowly and will increase blurring.

Title: IS lenses + long exposures
Post by: Mike W on December 30, 2007, 08:49:27 am

Thanks, jonathan.

I wasn't talking about freezing a moving train, but about negating "seismic vibration" when a train passes the camera on a tripod (when standing on the platform). I was hoping IS could solve that inconveniance.

thanks for the reply.

Title: IS lenses + long exposures
Post by: John Sheehy on December 30, 2007, 01:45:46 pm

Quote

I wasn't talking about freezing a moving train, but about negating "seismic vibration" when a train passes the camera on a tripod (when standing on the platform). I was hoping IS could solve that inconveniance.
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Like Jonathan says, it will drift if it's active, because it doesn't see; it responds to motion.  Now, at some time in the future, "Live view" could be used in conjuction with IS to help it see, and then it may work well on a tripod for long exposures (or even hand-held), but that would require a new IS communication with the body, for lens-based IS.

BTW, Some IS lenses disable the IS when they sense tripod-like stability, even when the switch is on.