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View Full Version : relative motion.....IS vs FPS



modm750
02-05-2008, 05:19 PM
In IS, the object is steady while the camera is in motion.
In FPS, the object is in motion while the camera is still. SO I believe you can use your FPS while the object is still to apply a IS technique. PLEASE correct me if I am wrong. :rolleyes:;):rolleyes::confused::rolleyes::cool::D

toriaj
02-05-2008, 05:27 PM
You mean Frames Per Second (FPS,) right? That refers to how many shots the camera can take in 1 second. A fast shutter speed "freezes" motion because it is so quick, and you don't need to take several shots in one second. Just one shot at 1/250 sec. or so will generally freeze any motion.

Image Stabilization (IS) is helpful when you need to use a long shutter speed because there isn't much light in the area. It is difficult to hold the camera steady for a longer shutter speed, because our hands shake. So IS enables you to use a longer shutter speed without camera shake. But it does NOT freeze motion. So if your subject was moving and your shutter speed was around 1/40 sec. or longer, you would get a picture with a nice clear background but a blurred subject. I hope that helps.

AdamW
02-05-2008, 06:38 PM
Tori's right. What's determines FPS speed is how fast the camera can write to the card and how big the memory buffer is and some other details. It really has not much to do with shutter speed, which can freeze the motion of a moving subject and to some extent compensate for camera movement.

JTL
02-06-2008, 01:47 PM
It also never hurts to keep the reciprocal shutter speed/focal length rule in mind...that is: When hand-holding, choose a shutter speed equal to or faster than your focal length to avoid camera shake.

The advantage of IS is that it generally allows you to break this rule by a couple of stops.

toriaj
02-06-2008, 09:44 PM
I use that rule of thumb constantly :) I always remember the crop factor, though. Many digital cameras (including mine) have a crop factor of 1.5 or close to it. So when using this rule of thumb, use 1/focal lengthx1.5. So if my focal length is 18mm, I can handhold down to (18+9) 1/27 sec. It is most difficult at the longer focal lengths though, where 300mm needs a shutter speed of 1/450 sec. That makes for some pretty bright light, and I'm sure the help of IS would be nice.

talkingdog
02-17-2008, 09:49 AM
Sometimes I use burst mode to help me with camera shake. Out of 5 or six shots one is usually not blurred. Sometime this helps when the shutter is just to slow, even with IS.

mjsneddon
02-19-2008, 03:04 PM
that continuous shooting thing to capture one that is clearly better than the others with regard to camera shake with some success.