#41 in a series of background briefs

The changing role of
Combined-exposure photos

On the reversal over the past two decades in the acceptance of “combined exposure” photographs

  • 1. Why does TTG allow for combining exposures when respected international news agencies have not traditionally allowed it?

    Because many millions of non-deceptive photos are now made every day with smartphones that instantly combine multiple exposures, all taken in a fraction of a second.

    The result is improved picture quality without any reduction in how realistic the photograph appears to viewers.

    (These are not your grandfather’s “double exposures.”)

    NOTE that this discussion refers only to photographs made without repositioning the lens or camera between exposures (see P3) and without depicting more than one arrangement of the scene (see P4).

  • 2. Before the year 2000 it was fairly unusual to deliberately combine two or more exposures in one photograph.

    • When exposures were combined back in the film era, the result was usually immediately apparent — as with a “double exposure” done for artistic reasons.

    • In news reportage, “combining exposures” was largely of unheard in the film era.

  • 3. But in the 21st century it is very common to combine two or more exposures in one photograph.

    • It happens many millions of times a day on smartphones, usually without the photographer even being aware of it (let alone them telling their smartphone to do so)

    • In the digital era — in contrast with the 19th and 20th centuries — “combining exposures” is no longer synonymous with “depicting multiple arrangements of the scene.”

  • 4. The public is still largely skeptical of combined-exposure photographs...

    . . . which may explain why smartphone manufacturers don’t make big deal out of how often their devices combine exposures to make photographs.

    • There is little general awareness of exposure-combining technologies like HDR, pixel-shifting, and focus-stacking.

    • Since those actions are routinely performed without making the photo look any less realistic, the popular perception lingers that “combining exposures” is typically done to make the scene appear differently in the photo than it would have appeared to someone at the scene.

  • 5. But in years to come, as increasing numbers of citizens’ smartphone photos will be used for spot-news reportage...

    . . . and now that most combined-exposure images on smartphones often look the same as the scene would have appeared to someone at the scene—

    — news organizations will for the first time have to identify which “combined-exposure” photos are trustworthy.

    Setting out clear parameters for making such photographs is part of TTG’s role (see link at the bottom of #6 below).

  • 6. One thing hasn’t changed:

    Combining photographs has always provided an entire additional set of ways to make images less trustworthy.

    That’s why in exchange for allowing combined images, the Trust Test imposes strict limits on how exposures may be combined in a TTG photograph.

    Those limits are all gathered into one list here

 

See also FAQ #1504