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GeertDD
17th of August 2003 (Sun), 11:26
Hi,
Usually I am about as shaky as the pope, on my SLR I can just manage the shutterspeed=1/focal length rule.
Yesterday evening I was taking some shots of a concert, and found myself in need of some longer shutterspeeds. I tried a method I once read on an other website, and it worked great!!! I took sharp, handheld shots at 1/15 sec and 1/20 sec, something I never managed before.

http://gddweb.org/154-5476_IMG.jpg

and an unedited 100% crop from the above picture:

http://gddweb.org/154-5476_IMGpart.jpg

Sharp, insn't it? And that for Tv=1/20 Av=2.5 ISO=50 Focal Length=15.8mm :)


So how does it work? Set your camera to continues shooting, shoot 5-7 consecutive photos and select the best one. The theory is that when the camera shakes, its movement is approximately periodical and you have points of zero and maximum speed. So if you shoot series of pictures probably one or more will be shot during the moment when the speed is zero. Mind that this is not the same as shooting 5 seperate shots, in that case you always shoot at the same moment in the periodical movement (because the movement is partially caused by pressing the shutter) .

For selecting the sharpest shot you don't have to studie every shot on your monitor, just look at the (jpeg) file-size. The largest file will be your sharpest shot.

http://gddweb.org/154-5461_IMG.jpg

gaz63
17th of August 2003 (Sun), 18:18
Nice !!!

io NightShade
17th of August 2003 (Sun), 21:38
"...largest file will be your sharpest shot."

I don't know much about cameras. Just got my first camera three days ago and it's a G3. But, is the aforementioned statement true? Just wondering if it is a theory or a fact.

Thanks,

JT

GeertDD
18th of August 2003 (Mon), 12:07
io NightShade wrote
is the aforementioned statement true? Just wondering if it is a theory or a fact.
JT

It is true for jpeg files, it is inherent to the compression that sharp edges take up more memory space than soft edges. It's also easy to check by shooting the same subject with good focus and with manually set bad focus.

On RAW files it is a bit more difficult to see, but since Canon RAW is a (losslessly) compressed format I've read claims that even RAW files differ in size due to different sharpness. But I've not had a chance to check if this is true.

Geert.