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#1 jorge gonzalez

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Posted 17 June 2007 - 01:57 PM

my film school just bought a camera (eclair NPR super16) and i need to know what kind of tests one must run on it to see how good it works, as well as tests on optics etc. i need to know this cause this is the first time we´ll work with film and the camera obviously is second hand.
thanx for any help you can give

jorge
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#2 David Regan

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Posted 17 June 2007 - 03:14 PM

I haven't had much experience running tests myself, so I'm sure there are many others, but one important one is scratch tests. Run short ends or just a couple feet of film through the camera, and then look at film you ran through, to ensure nothing is scratching the film in the mag or gate. This is actually something you should run often, but be sure to do it now especially.

Good Luck
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#3 Bryant Jansen

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Posted 17 June 2007 - 03:31 PM

my film school just bought a camera (eclair NPR super16) and i need to know what kind of tests one must run on it to see how good it works, as well as tests on optics etc. i need to know this cause this is the first time we´ll work with film and the camera obviously is second hand.
thanx for any help you can give

jorge


Doug Heart's book "The Camera Assistant" has a wealth of information on camera tests. It is a great resource to have around anyways.
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#4 Chris Keth

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Posted 19 June 2007 - 12:13 AM

Well, you should do mag tests like David describes. Make sure you do this on several speeds including sync speed, the lowest framerate and the highest framerate.

Steadiness test - you will use live film for this and get it processed. Shoot a star chart so it fills the frame and is in sharp focus. Underexpose this by a stop. Rewind the film in a bag and reload the magazine. Shoot the star chart again, also underexposed by a stop. This will superimpose two images of the siemans star over each other. It will be VERY obvious if there is a steadiness problem because a pattern in the stars will undulate or dance. Ideally, the image looks like a still frame.

You should test every lens in the package to see if the distance markings are correct. If they aren't correct, reject the lens and ask for another. If it's your lens, it needs service.

For zooms you should check to see that focus stays sharp throughout the zoom range. You should also check tracking of the zoom by framing so that the crosshair coincides with gridlines on a focus chart. Slowly zoom in and out and make sure that the center of frame does not wander off of the mark.

If you have lenses from different sets and you worry about them not matching, you may want to check the color cast of your lenses. Just shoot a greyscale under plain tungsten light on tungsten film. Viewing the processed film will show you if any of your lenses have a drastic color cast and if your lenses differ greatly in their color cast. You would be surprised. ;)

You can check the phase of the shutter like this: Draw an irregular squiggly line on the emulsion side of a piece of film. Let it dry completely because it is going in the camera. Thread this bit of film in the camera and then phase the camera while you look through the lens port. You should not see the squiggly line move but the irregularity of the line should tell you that the camera is moving film.


Other than these tests, build the camera and make sure it all fits together and works and you'll be good.
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Aerial Filmworks

The Slider

Glidecam

Opal

Gamma Ray Digital Inc

Visual Products

Rig Wheels Passport

Ritter Battery

CineLab

Tai Audio

Wooden Camera

Willys Widgets

Metropolis Post

FJS International, LLC

CineTape

Paralinx LLC

rebotnix Technologies

Abel Cine

Media Blackout - Custom Cables and AKS

Technodolly

Broadcast Solutions Inc