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<blockquote data-quote="WayneF" data-source="post: 369036" data-attributes="member: 12496">Yes, for focal plane shutter speeds faster than sync speed, the shutter speed (exposure time) and the shutter travel time are two very different concepts.from <a href="http://www.scantips.com/lights/flashbasics2c.html" target="_blank">Four Flash Photography Basics we must know - Maximum Shutter Sync Speed</a>A very interesting picture (a classic) using a focal plane shutter is <a href="http://www.largeformatphotography.info/forum/showthread.php?t=31903" target="_blank">this 1912 picture</a>&nbsp; by Jacques Henri Lartigue. The shutter travel motion can cause&nbsp; distortion of a moving subject. The shutter slit was moving down the&nbsp; picture there (upwards in the camera, but we see it after inversion).&nbsp; The spectators are leaning left because the 4x5 camera was being panned&nbsp; right, following the race car. Their feet were exposed earlier than&nbsp; their heads, at slightly different times, due to the moving slit, and&nbsp; the panned camera. The car was going faster yet, so it leans the other&nbsp; way. This classic picture is responsible for us imagining speeding&nbsp; wheels as being slanted ovals, at least in cartoons. Shutters are much&nbsp; faster today, but the fastest motion can still be an issue (see the FP&nbsp; flash picture of the grinding disk on next page). The narrow open slit&nbsp; can provide a very short (fast) exposure, but it takes much longer for&nbsp; this slit to travel across all of the frame. The curtains cannot open or&nbsp; close instantly.But yes, shutters are faster today, and &quot;film size&quot; is smaller (both effects are shorter travel time), so it becomes a minor effect today, hard to show except at fastest speeds. Sorry,&nbsp;&nbsp; I did think it was an unreal question.That referenced try was at 1/8000 second (was about no motion stopping capability of HSS flash, but it shows focal plane distortion):<a href="http://www.scantips.com/lights/flashbasics2b.html#speed" target="_blank">Four Flash Photography Basics we must know - Auto FP and HSS</a></blockquote>

[QUOTE="WayneF, post: 369036, member: 12496"] Yes, for focal plane shutter speeds faster than sync speed, the shutter speed (exposure time) and the shutter travel time are two very different concepts. from [url=http://www.scantips.com/lights/flashbasics2c.html]Four Flash Photography Basics we must know - Maximum Shutter Sync Speed[/url] A very interesting picture (a classic) using a focal plane shutter is [URL="http://www.largeformatphotography.info/forum/showthread.php?t=31903"]this 1912 picture[/URL] by Jacques Henri Lartigue. The shutter travel motion can cause distortion of a moving subject. The shutter slit was moving down the picture there (upwards in the camera, but we see it after inversion). The spectators are leaning left because the 4x5 camera was being panned right, following the race car. Their feet were exposed earlier than their heads, at slightly different times, due to the moving slit, and the panned camera. The car was going faster yet, so it leans the other way. This classic picture is responsible for us imagining speeding wheels as being slanted ovals, at least in cartoons. Shutters are much faster today, but the fastest motion can still be an issue (see the FP flash picture of the grinding disk on next page). The narrow open slit can provide a very short (fast) exposure, but it takes much longer for this slit to travel across all of the frame. The curtains cannot open or close instantly. But yes, shutters are faster today, and "film size" is smaller (both effects are shorter travel time), so it becomes a minor effect today, hard to show except at fastest speeds. Sorry, I did think it was an unreal question. That referenced try was at 1/8000 second (was about no motion stopping capability of HSS flash, but it shows focal plane distortion): [url=http://www.scantips.com/lights/flashbasics2b.html#speed]Four Flash Photography Basics we must know - Auto FP and HSS[/url] [/QUOTE]

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