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#1 M1A

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Posted 04 July 2006 - 03:07 PM

Maybe someone can point in the direction of where I can find an image of one. I've tried to pull one up on google and this website with no luck. Thanks.
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#2 David Mullen ASC

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Posted 04 July 2006 - 03:29 PM

Maybe someone can point in the direction of where I can find an image of one. I've tried to pull one up on google and this website with no luck. Thanks.


A registration test just involves double-exposing a simple grid pattern over itself, slightly offset the second time, so that you spot relative movement. In a camera with perfect registration, the two grids over each other should look like a single grid with twice as many lines. Otherwise, you see one grid shaking or bouncing a little relative to the other one.
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#3 M1A

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Posted 04 July 2006 - 04:34 PM

A registration test just involves double-exposing a simple grid pattern over itself, slightly offset the second time, so that you spot relative movement. In a camera with perfect registration, the two grids over each other should look like a single grid with twice as many lines. Otherwise, you see one grid shaking or bouncing a little relative to the other one.


I'm trying to test a 4008 with a Frame Master. I understand that the film can come to rest in slightly different positions, due to the pressure plate built into the cart. The frame master will add to the thickness of the pressure plate, in turn providing a small amount more tension on the film, thus possibly hendering each frame from stopping in different positions.

I want to see how drastic the difference will be between the frames themselves. So is a double exposure necessary in this case? If I was to double expose, it would seem that I would just get 2 shaking grids.
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#4 Darren Blin

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Posted 04 July 2006 - 05:57 PM

I want to see how drastic the difference will be between the frames themselves. So is a double exposure necessary in this case?

Yes, because otherwise how would you know if it was the camera or the projector you're viewing the test on that has bad registration?
Rewinding a Super-8 cartridge by hand to double expose is going to be a bit of a bother though.

Also, don't forget to underexpose by a stop on each pass.

Edited by Blin, 04 July 2006 - 05:58 PM.

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#5 M1A

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Posted 04 July 2006 - 06:40 PM

Yes, because otherwise how would you know if it was the camera or the projector you're viewing the test on that has bad registration?
Rewinding a Super-8 cartridge by hand to double expose is going to be a bit of a bother though.

Also, don't forget to underexpose by a stop on each pass.


I was planning on having it transferred to tape and then inspect the outcome.

The rewind will be easy because mine is actually a ZMII so it has that handy button you can depress to stop the core from rotating. Then I just run the film backwards via the knob on my camera motor.

Why is it just one stop by the way? Obviously it's because the film has been exposed to light, but what is the calculation that determines one stop.
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#6 David Mullen ASC

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Posted 04 July 2006 - 06:49 PM

Each stop is the equivalent of doubling the amount of light or cutting it in half. So if you give each pass 1/2 the exposure necessary (i.e. underexpose by one stop) then two passes will equal full exposure.

With good registration, there should be little shaking to none between the two grids. Without the two exposures, just a single grid, you wouldn't know if the shaking was the projector or telecine, or on the film itself.
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#7 M1A

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Posted 04 July 2006 - 07:25 PM

Each stop is the equivalent of doubling the amount of light or cutting it in half. So if you give each pass 1/2 the exposure necessary (i.e. underexpose by one stop) then two passes will equal full exposure.

With good registration, there should be little shaking to none between the two grids. Without the two exposures, just a single grid, you wouldn't know if the shaking was the projector or telecine, or on the film itself.


Gotcha. Thanks for the help. I would still like to take a look at a registration chart if someone knows where I can find one.
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#8 David Mullen ASC

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Posted 04 July 2006 - 07:50 PM

Gotcha. Thanks for the help. I would still like to take a look at a registration chart if someone knows where I can find one.


It's a plain grid -- you can make your own on a computer and print it out. Just make sure you mount it to something flat & rigid and when you shoot, both it and the camera are really stable, rigid.

Just a bunch of crisscrossing lines like on graph paper...
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#9 M1A

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Posted 04 July 2006 - 08:13 PM

It's a plain grid -- you can make your own on a computer and print it out. Just make sure you mount it to something flat & rigid and when you shoot, both it and the camera are really stable, rigid.

Just a bunch of crisscrossing lines like on graph paper...



I was under the impression there was more to it than that. I must be confusing it with another chart. Thanks again.
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#10 David Mullen ASC

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Posted 04 July 2006 - 08:31 PM

I was under the impression there was more to it than that. I must be confusing it with another chart. Thanks again.


Maybe you're thinking of a resolution chart, not a registration chart.
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#11 M1A

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Posted 04 July 2006 - 09:57 PM

Maybe you're thinking of a resolution chart, not a registration chart.


One other question. Should I test it at different focal lengths. I have a 6-66mm lens and I was thinking of shooting around the middle.
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#12 S8 Booster

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Posted 09 July 2006 - 10:40 AM

registration card from shhot8:

Why not just shoot on a registration chart like this...

Posted Image

..then rewind the film, aim 10-30 mm below and to the right of the original image, then shoot again? You will not only see registration but also breathing at the center of the film.
 


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