Do you know much about shutter speed?

[James Carver]

i'm still learning the HVX and filmmaking as well and have a good grasp on the other parts of the camera, but one thing that is not discussed much in the instructions is shutter speed.

toggling with the different shutter speeds what type of effect will this have on the footage i shoot? basically i know the shutter allows a certain amount of light inside the camera but....so what? what is that doing and how can i use this to my advantage? in what situations would i need to adjust the shutter speed?

thanx in advance....

[Barry Green]

Shutter affects exposure, and also blur. The shorter your shutter speed (like, 1/2000) you will have very crisp footage with no motion blur. The longer your shutter (like, 1/24) the more motion blur will be present, but the more light sensitivity you get.

Film is typically shot with shutter times from around 1/40 to 1/60. Much faster or slower than that and you'll start producing atypical looks, looks that don't really look like film.

Perhaps the most visible example is the somewhat recent trend of hyper-stuttery motion, such as in Saving Private Ryan, Gladiator, and 28 Days Later, all of which employed very short shutter speeds. Longer shutter speeds have been used in Ali and Collateral.

If you want to do a streaks/blur timelapse style of shoot, you can get exposure times as long as 1/2 second by putting the camera in 2fps mode and choosing a 350-degree shutter. That gives exaggerated streaks on the lights of passing cars, etc.

[James Carver]

thanks barry, i am going to try that timelapse advice for streaks tomorrow downtown.

in a movie like Saving Private Ryan or Gladiator are you saying they used shorter shutter speeds than 1/60? if so, about what speed shutter was that shot at to get that hyper-stuttery type of motion?

[Robert Lane]

Originally Posted by Barry Green

If you want to do a streaks/blur timelapse style of shoot, you can get exposure times as long as 1/2 second by putting the camera in 2fps mode and choosing a 350-degree shutter. That gives exaggerated streaks on the lights of passing cars, etc.

That shutter speed is only available by using your "cheat" script in your book, right? Or am I confusing this with another setting?

[Barry Green]

For frame rates slower than 12fps yes, you have to edit the scene file with a text editor.

For SPR shutter speed they used a 45-degree shutter, which you can emulate by setting the HVX in FILM CAM mode, choosing the syncro-scan shutter speed, and changing it in the scene file to 45.0d.

For 28 Days Later, I believe they used something like 1/2000.

[Perrone Ford]

What kind of effect would you see from a high shutter speed with a very low fps? I am wondering if you could get something like the scenes in Bram Stoker's Dracula. I am thinking of a night scene where the beast comes to visit Lucy in the night. It was VERY eerie and quite cool.

I am also wondering about a scene in that movie where the count visits London (or whatever city) and the street peddler is saying, "Come see the amazing chromatograph!" The video is quite stuttery and reminded me of what you'd see when flipping pages manually with drawings on them.

[James Carver]

thanx guys, oh and for reference....what does the 2000 represent in a shutter speed of 1/2000?

[R Geoff Baker]

1/2000 -- one two thousandth of a second, a second divided into two thousand units ... one of them.

Normal shutter speed is the a function of the frame rate -- 60 fields per second equates to a normal shutter speed of one sixtieth of a second: As soon as one field is recorded, the shutter opens for the next, closing when it is time to open for the next, et cetera. Note that 'open' and 'close' is legacy terminology, like dialing a phone, but the concept is identical.

If you shoot with a shutter speed shorter than the duration of each field (or frame) you end up with a temporal discontinuity -- the shutter is closed, motion that is taking place 'in the real world' is not being filmed ... so when the next field begins, the objects appear to 'jump' in location. In this context, motion blur is the ordinary and correct presentation -- it looks at best odd, and worst disconcerting to see objects jump on screen from one location to the next.

Longer shutter speeds are handled differently but different devices -- my venerable VX1000 had the ability to buffer a frame and then record it across many frames -- so a half second shutter speed resulted in a shutter opening, the frame being recorded (identically) across fifteen frames, then the shutter closing. If there were objects on screen, they left a trail as they moved across a given frame -- in the end there was no temporal discontinuity, so objects didn't jump ... but they did smear as they moved.

Some shooters claim faster shutter speeds are 'better' for high motion events, but this is not entirely true -- any given frame if examined will appear to be 'sharper' as there will be less motion smear, but viewed in context the moving objects will jump between frames, and that can be a more annoying result than motion smear.

HTH

GB