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class="style18"> Time Lapse Exposure Compensations

>Published : 9th Dec. 2008

>Hey guys,

I am going to be shooting several nights of time lapse of the moon pretty soon. I am shooting on an old Mitchell with an intervalometer. I have decided to shoot somewhere around a frame every 20 seconds for two hours on Kodak 5218. This will give me 15 seconds of footage projected normally.
 

I have been reading a lot on here about exposures people are using to shoot the moon and most people say it will be metering anywhere from a 5.6 to an 11 on a clear night.

>I guess I am thinking way to hard about the shutter side of all of this and I have now confused myself. I cant seem to figure out what the correct shutter speed/ angle I will need to accomplish this. The shutter as most cameras have goes from 180 to 0. Since it will only be doing less than 1fps how do I make sure the shutter is going to be correct for the exposure that I will need.

>Thanks so much guys,

>Terry Zumalt
Chicago


>Terry, I suggest you shoot with the shutter set to 180. I have shot full moon time lapse and you should have no trouble By the way the moon will rise from bottom left of frame to top right(I wonder what happens is the southern hemisphere?

Best,


John Babl
Miami


class="style19">>>Terry, I suggest you shoot with the shutter set to 180. I have shot full moon time lapse and you >>should have no trouble By the way the moon will rise from bottom left of frame to top right(I wonder >>what happens is the southern hemisphere

>It rises from the bottom right to the top left!

>Roger Buckingham ACS

>Southern hemisphere


>Terry Zumalt wrote:

>>> I cant seem to figure out what the correct shutter speed/ angle I will need to accomplish this. The >>shutter as most cameras have goes from 180 to 0. Since it will only be doing less than 1fps how >>do I make sure the shutter is going to be correct for the exposure that I will need.

>I think this is what you're asking for.

>Shutter Angle/360 X frame rate (frames per second) = exposure time, thus 180/360 x 1 (fps) = 1/2 For normal filming: 180/360 x 24(fps) = 1/48 The intervalometer that you are using may allow you to change the shutter speed independent of the interval. In other words, you may expose one frame every 20 seconds but still have an exposure time of 1/48 second rather than 10 seconds.

>Brian Heller
IA 600 DP


>Terry Zumalt wrote:

>> In other words, you may expose one frame every 20 seconds but still have an exposure time of
> 1/48 second rather than 10 seconds.

>Intervalometer systems have different specs for shutter speed w 180 deg shutter. Some systems ( controller plus camera type) can only achieve a minimum shutter speed of 1/4 sec or 1/2 second. I have a \Mitchell/Norris system that does 1/16 sec exposures w 180 degree shutter. On a 35 mm Mitchell with a Norris controller you should be \able to use the camera's variable shutter to get exposure speeds of:

>90 deg = 1/32 sec
45 deg = 1/64
22 deg = 1/128
11 deg = 1/256

>Mark Smith
DP Nyc.


>Worked with a Mitchell that had just been reflexed with a mirror shutter, came back from the modification, and put it into service.

>Shooting on two's we noticed a weird exposure flicker on the one of the frames, every pair.

>It turns out that the shutter was off somewhere and dragging against the aperture plate slightly.
--
Steven Gladstone
New York Based Cinematographer
Gladstone Films
www.gladstonefilms.com


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