View Full Version : Regarding Shutter Speed


TingSern Wong
December 19th, 2007, 01:24 AM
I am shooting in HD - 720p on HVX202. Normally, the camera default shutter speed is 1/24. If I shoot in low light, and am using tripod, I can reduce the shutter speed to 1/12 - the lowest speed it will go.

Questions -

a) How does 1/12 speed affect the motion of objects recorded on camera?

b) Does it affect the "slow and fast motion" performance of the camera?

c) Compared with "Gain Control" - which is better? Increase gain or reduce the shutter by 1 stop?

I know Auto Focus will be slower - but, I am using mostly MF - so that's a non-issue for me.

Douglas Villalba
December 19th, 2007, 09:29 AM
I am shooting in HD - 720p on HVX202. Normally, the camera default shutter speed is 1/24. If I shoot in low light, and am using tripod, I can reduce the shutter speed to 1/12 - the lowest speed it will go.

Questions -

a) How does 1/12 speed affect the motion of objects recorded on camera?

b) Does it affect the "slow and fast motion" performance of the camera?

c) Compared with "Gain Control" - which is better? Increase gain or reduce the shutter by 1 stop?

I know Auto Focus will be slower - but, I am using mostly MF - so that's a non-issue for me.
Normal shutter speed when shooting at 24 fps is 180 degrees or 1/48th second. 1/24 sec. is good enough for talking heads or very minor motion.

Anything lower slower will look very soft with any kind of motion.

Whenever I have to shoot in low-light the lower I would go is 1/24th with 6 db gain. If at that setting you get proper exposure then you would get a good image without grain (noise).

The HVX likes over exposure(1/2 f tops) better than under exposure.

Barry Green
December 19th, 2007, 11:42 AM
a) How does 1/12 speed affect the motion of objects recorded on camera?
It will do "frame accumulation" and you'll end up with 12 distinct frames per second, each will be quite blurry.

b) Does it affect the "slow and fast motion" performance of the camera?
Well, it limits you to 12 distinct frames per second (you cannot have a faster frame rate than your exposure time without seriously harming the laws of physics).

c) Compared with "Gain Control" - which is better? Increase gain or reduce the shutter by 1 stop?
gain = noise, but normal motion
1/12 shutter = no noise, but blurrier motion

Your choice.

TingSern Wong
December 19th, 2007, 01:25 PM
Thanks for the reply. I did some experiments just now. At 1/12 second, even panning at a very slow speed, I can see the image jumps - not smooth. Looks like I have to abandon 1/12 second shutter and stick to 1/25 (PAL) as the slowest I will go then.

Dan Brockett
December 19th, 2007, 03:34 PM
Thanks for the reply. I did some experiments just now. At 1/12 second, even panning at a very slow speed, I can see the image jumps - not smooth. Looks like I have to abandon 1/12 second shutter and stick to 1/25 (PAL) as the slowest I will go then.

I agree with Barry. I used to shoot a lot of interviews with 1/24th for the extra light levels but even they have a tendency to look rather soft. I cna't imagine using 1/12th of a second shutter. The camera definitely looks better with 1/48th (180 degree) shutter. These days, I just bring the light levels up and use 180 degree. The end result looks sharper and better to my eye.

Dan

TingSern Wong
December 19th, 2007, 11:26 PM
I agree with Barry.... These days, I just bring the light levels up and use 180 degree.
Dan

The key here is - you can bring the light levels up. But I can't. Filming in national parks, inside rainforests, Himalaya mountains, etc ... it is just impossible. I just have to make do with whatever sunlight there is available.