Proper Exposure to obtain a "Film Look" using an Xl1s at DVinfo.net

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Old April 14th, 2005, 03:56 PM   #1
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Proper Exposure to obtain a "Film Look" using an Xl1s

We are shooting a film using Canon xl1s's.

Our director wants all shots to be in Frame Mode with an exposure of 1/60th of a second.

Since we are using frame mode, we are getting 30 frames per second.

I feel that we are not necessarily restricted to 1/60 of a second exposure per frame, that we should be able to use a wide range of exposure values, if necessary, so we can use a desirable aperature. I feel that the exposure value may be adjusted if we want to create a blur or quick exposure to stop fast action.

I do not pretend to be an expert, I just want to fully understand the steps necessary to obtain a "Film Look".

I feel that when we use frame mode, we will get 30 frames a second, and the exposure is just the amount of time the electronic shutter is open to properly obtain the correct amount of light, which of course varies with the aperature.

I am interested in the expert's opinions on this subject, and the opinions of anyone with practical experience.

Thank you.
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Old April 15th, 2005, 09:49 PM   #2
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I can't believe i never thought of playing with the shutter speed on my XL2 to change the aperature like that, i should try it... good call.
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Old April 16th, 2005, 01:59 PM   #3
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Perhaps the director is calling for 1/60th because it is the closest to 1/48th, the cine exposure time for 24 fps (light meters call it 1/50th). However, there is no reason not to use other shutter speeds as a creative choice. I recently used short exposure times on a quick cut handheld piece to create some visual interest, up to 1/250th (which duplicates the 45 degree shutter look as seen in "Saving Private Ryan", "Gladiator" etc). I was shooting in frame mode incidentally.

While some of the automatic modes on the XL series are based on the still camera model (shutter priority, aperture priority), suggesting that if one wants to maintain a given exposure or f-stop you simply adjust the shutter to deliver a consistent exposure, in the cine world the shutter angle is always a creative decision and very rarely used as an exposure compensator.
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Old April 16th, 2005, 03:02 PM   #4
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Dear Charles

Thanks for the information. I just researched "Shutter Angle" so I could properly respond to your post.

It seems that we can adjust our expsose times to create a motion blur or to stop fast action and this is similar to the effects of adjusting the shutter angle in a cine camera.

Charles, I appreciate your assistance.

Thank you,
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Old April 17th, 2005, 12:33 PM   #5
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Yup, that's dead right Dan.

In fact, the effect is identical to changing the shutter angle in a cine camera - the reason why it is stated as an angle is that the shutter in a cine camera is a spinning disk with a "pie slice" shape missing - this is the area that lets the light in to expose the film. By changing the size of this slice (the shutter angle, or angle between both edges of this wedge) you change the amount of time the shutter is open for as the disk spins...

So, for instance, a 180 degree shutter angle gives a shutter speed of 1/48th (24 fps and the shutter is open half the time), whereas a shutter angle of 90 degrees gives a shutter speed of 1/96th (or 1/100th in reasonable terms) as the shutter is now only open for one quarter of the cycle.

If you set your shutter speed on the XL1 to 1/100th you will get exactly the same effect as if you set the shutter angle on a cine camera to 90 degrees - they're just two different ways of expressing the same thing, due to different shutter mechanisms in the cameras.

Hope that helps rather than hinders!!!
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Old April 21st, 2005, 12:43 AM   #6
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Yes, but there is a difference. Fast shutter will get you a very crisp still picture. But with video/film, you've got moving pictures, and that crispness will start to give you a strobing effect very quickly. You have to manage the motion of the camera and the talent (slow them down) so this is not distracting to watch.

I shot some stuff at 1/100 one time, not a huge increase, and it was very apparant that something was different. Use with caution. Take some test shots.
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Old April 21st, 2005, 04:56 PM   #7
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In 28 Days Later, the director opted for using fast shutter speeds on several scenes with fast action. This resulted in very choppy movement due to the lack of motion blur. I'm assuming he did this on purpose, making the zombies move in a slightly less 'normal' way.

I other words it's all about the look you're trying to achieve. Sticking to 1/60 on all shots seems a bit limiting, but maybe you should ask the director why he wants it so? Maybe he has a good reason for it...
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Old April 21st, 2005, 11:30 PM   #8
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Dear Joshua, Jon, Dominic, Dave, and Charles,

Thanks for your insight and good advice.

I will run some tests. This appears to be the best solution, so we can judge the difference.

Thanks again for all of your help.
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Old April 22nd, 2005, 01:49 AM   #9
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Don't overlook "clearscan". Although it's trumpeted as a feature that enables you to shoot CRT screens, it's actually just a finely tuneable shutter speed.
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