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<blockquote data-quote="Eyelight" data-source="post: 369821" data-attributes="member: 24753">Been studying on bird flight and freezing their variety of motions.&nbsp; Here is the blackbird with the PS grid turned on and set to the size of the D7100 sensor.&nbsp; The main grid lines represent millimeters and the lesser tenths of millimeters.&nbsp; So, this is the image of the bird sized to the sensor.Shutter Travel: The bird size on sensor is roughly 5.72 mm.&nbsp; Shutter curtain with a travel time of 1/250 top to bottom will pass the bird in 1/681 second.&nbsp; Just considering roughly 1 inch of wingtip (about 1 mm on the sensor), the curtain will pass it in 1/3900 second and pass each tenth millimeter of image in 1/39,000 second.In a shot like this the flight speed is offset by panning the camera and effectively reduced to where the body and head is perceptibly sharp.&nbsp; Wings are a different matter.&nbsp; Depending on the movement and angle of movement, the wingtips move across the sensor at a variety of speeds, but the fastest would seem to be the forward/upward movement across and parallel with the sensor plane.Assuming a few numbers, such as 11.25&quot; average b-bird wing length, WAG of 17.67&quot; wingtip travel and 10 wing beats per second gives an average wingtip speed of 15.6 meters per second in real life.&nbsp; The bird is reduced in size by the lens and this reduces the speed relative to the shutter travel speed (noted above).&nbsp; The duration of the shutter speed then captures a fraction of the wingtip movement of roughly 0.10 mm.&nbsp; Hard to tell because the screen capture of the blackbird is not so high res, but it looks like the wingtip may have moved about that much.[ATTACH]119723[/ATTACH]Edited to add:&nbsp; The sizing of the grid is based on the image being a full uncropped&nbsp; image.&nbsp; If the image was cropped then the bird would be smaller on the&nbsp; sensor and movement in relation to the sensor and shutter would be less.</blockquote>

[QUOTE="Eyelight, post: 369821, member: 24753"] Been studying on bird flight and freezing their variety of motions. Here is the blackbird with the PS grid turned on and set to the size of the D7100 sensor. The main grid lines represent millimeters and the lesser tenths of millimeters. So, this is the image of the bird sized to the sensor. Shutter Travel: The bird size on sensor is roughly 5.72 mm. Shutter curtain with a travel time of 1/250 top to bottom will pass the bird in 1/681 second. Just considering roughly 1 inch of wingtip (about 1 mm on the sensor), the curtain will pass it in 1/3900 second and pass each tenth millimeter of image in 1/39,000 second. In a shot like this the flight speed is offset by panning the camera and effectively reduced to where the body and head is perceptibly sharp. Wings are a different matter. Depending on the movement and angle of movement, the wingtips move across the sensor at a variety of speeds, but the fastest would seem to be the forward/upward movement across and parallel with the sensor plane. Assuming a few numbers, such as 11.25" average b-bird wing length, WAG of 17.67" wingtip travel and 10 wing beats per second gives an average wingtip speed of 15.6 meters per second in real life. The bird is reduced in size by the lens and this reduces the speed relative to the shutter travel speed (noted above). The duration of the shutter speed then captures a fraction of the wingtip movement of roughly 0.10 mm. Hard to tell because the screen capture of the blackbird is not so high res, but it looks like the wingtip may have moved about that much. [ATTACH=CONFIG]119723._xfImport[/ATTACH] Edited to add: The sizing of the grid is based on the image being a full uncropped image. If the image was cropped then the bird would be smaller on the sensor and movement in relation to the sensor and shutter would be less. [/QUOTE]

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