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#1 Tim Carroll

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Posted 22 August 2007 - 09:35 AM

Looking at an Arriflex IIC and I'm a little confused. I want to shoot 1.85. The camera has a Full Aperture gate (4-perf), and an Academy ground glass.

If my understanding is correct, the full aperture gate is wider than what I can see through the Academy ground glass. And according to ARRI, I cannot get a full aperture ground glass for the Arriflex IIC.

I can get a 1.85 ground glass to use with the camera, but it would seem that I still would not be able to see the whole full aperture, since the ground glass is the same as the Academy one for the camera, just with the little hash marks on top and bottom to show the 1.85 frame.

I want to use the full aperture, with the thought of, "If I'm gonna be shooting 35mm, I might as well use all the real estate available to me." But how does one accomplish this?

Is full aperture just hype, since you can't really see what you are getting on the "far side" of the frame, since the Academy ground glass won't show that?

Any and all assistance on this would be greatly appreciated.

Thanks,
-Tim
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#2 Stephen Williams

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Posted 22 August 2007 - 09:49 AM

Is full aperture just hype, since you can't really see what you are getting on the "far side" of the frame, since the Academy ground glass won't show that?

Thanks,
-Tim


Hi Tim,

Many older Arri Cameras viewing system (including the Arri III) don't show you the FULL area. Also the Arri 2 & 3's mirror's spins top to bottom, if you recenter the lens mount, many wider lenses will hit the mirror.

Quite a few people have successfully shot 'Fred Flintstone S35' you just need to take care of framing!

Clairmont Cameras have modified eyepieces for their rental Arri III's so I am sure you could do that on your Arri II

Mitchell's do show the full silent aperture, they were designed before sound. This is one reason along with their steadiness that they are often used as effects cameras today.

Stephen
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#3 Paul Bruening

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Posted 22 August 2007 - 10:14 AM

Hey,

I cut an aperture plate on my IIB for full frame width. I found out afterwards that there's no full frame optics for it. It didn't seem too unreasonable to just "Brain-frame" the image. You only have to compensate in your noodle for the additional useful frame. While that's not precise, it's usable for most ordinary shots. You can still do all of the important things like critical focus, et-al.

Hey Stephen,

What the heck is "Fred Flintstone S35?"
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#4 Tim Carroll

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Posted 22 August 2007 - 11:06 AM

Also the Arri 2 & 3's mirror's spins top to bottom, if you re-center the lens mount, many wider lenses will hit the mirror.


Stephen.

Well if the lens mount was re-centered, and this IIC has a PL mount, so I would suspect that re-centering may have taken place, then that would make the situation even worse. Not only can you not see the whole frame, but the frame is now offset from what you are seeing in the ground glass.

-Tim
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#5 John Sprung

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Posted 22 August 2007 - 12:38 PM

I cut an aperture plate on my IIB for full frame width. I found out afterwards that there's no full frame optics for it.

That's correct. The full frame finder and removable ground glass was introduced with the IIC.



-- J.S.
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#6 Stephen Williams

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Posted 22 August 2007 - 02:33 PM

Hey Stephen,

What the heck is "Fred Flintstone S35?"


Hi Paul,

It's the same as "Brain-frame", the term came from discussions on CML, however the conversation my have gone "off list" by that stage.

Stephen
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#7 Stephen Williams

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Posted 22 August 2007 - 02:39 PM

Stephen.

Well if the lens mount was re-centered, and this IIC has a PL mount, so I would suspect that re-centering may have taken place, then that would make the situation even worse. Not only can you not see the whole frame, but the frame is now offset from what you are seeing in the ground glass.

-Tim


Hi Tim,

Sounds like the lens mount was re-centered, take care when renting lenses, Zeiss 16mm will be an issue for sure!

The down side of not re-centering is an issue with Zooms not tracking / Vignetting. Lenses wider than 18mm, the distortion starts looking lopsided!

Stephen
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#8 Tim Carroll

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Posted 22 August 2007 - 03:46 PM

Hi Tim,

Sounds like the lens mount was re-centered, take care when renting lenses, Zeiss 16mm will be an issue for sure!

The down side of not re-centering is an issue with Zooms not tracking / Vignetting. Lenses wider than 18mm, the distortion starts looking lopsided!

Stephen


Stephen,

I talked to the person who did the lens mount and it was not re-centered on the full aperture gate. It is still centered for Academy.

This stuff makes my brain hurt, but just to see if I have this straight:

Academy aperture is: 21.95mm x 16.00mm
Full aperture is: 24.89mm x 18.67mm

So you are picking up real estate on top and bottom, as well as adding almost 3mm of real estate to one side of the image.

Now from what I have heard, the Arriflex 2C, with it's improved viewfinder compared to the 2B, will show the whole image area from top to bottom, so the whole 18.67mm will be visible through the viewfinder (I guess around the outermost top and bottom edges of the ground glass), but the extra 3mm of image area on the one side (the soundtrack side) will not be visible in the viewfinder. Am I understanding that correctly?

Thanks,
-Tim
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#9 Stephen Williams

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Posted 22 August 2007 - 03:56 PM

Stephen,

I talked to the person who did the lens mount and it was not re-centered on the full aperture gate. It is still centered for Academy.

This stuff makes my brain hurt, but just to see if I have this straight:

Academy aperture is: 21.95mm x 16.00mm
Full aperture is: 24.89mm x 18.67mm

So you are picking up real estate on top and bottom, as well as adding almost 3mm of real estate to one side of the image.

Now from what I have heard, the Arriflex 2C, with it's improved viewfinder compared to the 2B, will show the whole image area from top to bottom, so the whole 18.67mm will be visible through the viewfinder (I guess around the outermost top and bottom edges of the ground glass), but the extra 3mm of image area on the one side (the soundtrack side) will not be visible in the viewfinder. Am I understanding that correctly?

Thanks,
-Tim


Hi Tim,

Basically you don't see the 3mm extra on the left is correct, your probably framing for 1:1.85 so you should mark the ground top & bottom and make a center cross, your good to go!

Most primes will cover without issue but take care with matte boxes etc, A film test is recommended!

Stephen
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#10 jan von krogh

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Posted 22 August 2007 - 05:09 PM

Most primes will cover without issue but take care with matte boxes etc, A film test is recommended!
Stephen

I second that - we had to learn it looong ago the expensive way that a test would have been wise....
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