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Arri SR3 footage issue


Kyle Perritt

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I've been testing some old cameras lately and and shot a couple test rolls through an SR3 - one roll turned out fine. The other one had a weird, ghosted image that I can't quite figure out and I'm guessing someone here will know what this is immediately. (disclaimer: I'm a digital guy and relative noob to film) 

I've uploaded some grabs.

Screen Shot 2020-06-29 at 9.30.31 PM.png

grab2.jpg

Screen Shot 2020-06-29 at 9.30.58 PM.png

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It feels like maybe the  pressure plate on that one mag might need some love. The shiny metal as you're loading film into magazine is the pressure plate which holds the film at a certain pressure against the gate. If you have film bouncing back and forth between the pressure plate and the gate might cause it.

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The Arriflex 16 SR 3 has a register pin that locks the film during exposure. Your camera needs to be inspected by a technician. Even if a loop was too tight something like that shouldn’t have occurred. Too tight loops can pull the pressure plate up which results in out-of-focus images.

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Hard to see the exact issue with such low res frames, but a double image is very unusual with a pin registered precision camera like an SR3. A shutter timing error is virtually impossible because the timing is mechanically linked within the movement ie no belt slippage or such is possible. 

I’d check that the issue is on the film itself and not a scanning problem.

If it is on the film, was it just one mag for both the good and bad footage? Same lens? Any noise difference while shooting? Experienced loader? Actual footage available rather than low res frames?
 

 

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I remember taking a second look at this when we scanned it and talked to Kyle about this issue. I recall a slight frameline flutter and I think this was scanned concurrently with the other roll on the Spirit-2K to 1080P which did not have the flutter.

Possible mis-load in the SR3 mag where the loop goes under the plate guides and or too small a loop? Maybe the pulldown and pin were just "picking" at the perf.

If you want to send it back to the lab we can take a look at the perfs and see if there is any deformation on the bench.

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Hey thanks for the replies! I didn't see any notifications for these so I'm just now seeing this. Excuse the low res uploads, I'm still figuring out the ropes to posting here  

On 6/30/2020 at 12:51 AM, Tyler Purcell said:

Can you send a video? I'd love to see the frame line in motion. 

Cutting a clip now to upload

On 6/30/2020 at 1:24 AM, Simon Wyss said:

The Arriflex 16 SR 3 has a register pin that locks the film during exposure. Your camera needs to be inspected by a technician. Even if a loop was too tight something like that shouldn’t have occurred. Too tight loops can pull the pressure plate up which results in out-of-focus images.

I don't own the camera but when I got the footage back I asked the owner when the last time it's been serviced and the response was a shrug - which is a problem. I've been testing some old, good but neglected cameras recently - they're essentially free for me to use, so... I guess you can say I've been hoping for the best? It's worked out maybe half the time.

On 7/1/2020 at 11:19 PM, Dom Jaeger said:

If it is on the film, was it just one mag for both the good and bad footage? Same lens? Any noise difference while shooting? Experienced loader? Actual footage available rather than low res frames?

Had two magazines - One was fine. The problem footage is all on a single magazine. There was also a diagonal stripe light leak about every 6-10 seconds on that roll so from what you guys are saying about the pressure plate on the magazine I feel like all my problems could becoming from this single magazine, hopefully.

On 7/2/2020 at 1:39 AM, Robert Houllahan said:

If you want to send it back to the lab we can take a look at the perfs and see if there is any deformation on the bench.

  Hey Robert, these tests are mainly for my eyes so I'm not worried about rescanning - I just shot some charts today with the same setup and both magazines that I loaded myself to see if I get the same problem.

 

Thanks everyone

Kyle

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I must advocate for the camera now and speak against the scan. Perforation, frame line and general steadiness are excellent.

Not saying scanning, just the actual scan. I have the impression that the film fluttered on the scanner in depth, along the optical axis. Concurrently the register pin or the transport claw can have pulled on or pushed the film during exposure in the sense of Robert Houllahan’s post. Has the stock been rolled through a counter or synch roller? Nicked perforation hole edges can cause a lot of troubles in a camera.

 

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11 hours ago, Simon Wyss said:

I must advocate for the camera now and speak against the scan. Perforation, frame line and general steadiness are excellent.

Not saying scanning, just the actual scan. I have the impression that the film fluttered on the scanner in depth, along the optical axis. Concurrently the register pin or the transport claw can have pulled on or pushed the film during exposure in the sense of Robert Houllahan’s post. Has the stock been rolled through a counter or synch roller? Nicked perforation hole edges can cause a lot of troubles in a camera.

 

Hey Simon, I ran some more film through the camera yesterday and sent it to the lab. Used the same two magazines that I did on the first test, I'm just very curious to see what happens. Was never ran through a counter or synch roller.  

10 hours ago, Robin Phillips said:

just a side note, if you didnt measure focus you should get your flange depth checked (or lenses colimated). this seems kinda soft for super16 on an sr3

My other roll of footage from a separate mag looked fine - same shots / subject distance / lens etc

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On 7/8/2020 at 10:02 AM, Simon Wyss said:

I must advocate for the camera now and speak against the scan. Perforation, frame line and general steadiness are excellent.

Not saying scanning, just the actual scan. I have the impression that the film fluttered on the scanner in depth, along the optical axis.

Nope.

Scanned on a LaserGraphics Scan Station 5K to 2.5K overscan, this is an area sensor scanner which uses machine vision based GPU X - Y registration and exposure and camera trigger times at as little as 50 microseconds. The film can physically move around in the gate all it wants actually but is locked on the perforations in the GPU CUDA processing and the perforations and keycode and grain are sharp and are completely steady in the scan.

The issue in camera also accounts for the lack of overall sharpness in the image as there is actually a very slight double image recorded to the film.

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Thanks for the elucidation, I am no expert with electronics.

The only failure left possible is film movement along the optical axis which implies the film pulling the pressure plate back. From what I see on the video the film is ripped off position by a too short lower loop during the last part of exposure.

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13 hours ago, Robert Houllahan said:

Nope.

Scanned on a LaserGraphics Scan Station 5K to 2.5K overscan, this is an area sensor scanner which uses machine vision based GPU X - Y registration and exposure and camera trigger times at as little as 50 microseconds. The film can physically move around in the gate all it wants actually but is locked on the perforations in the GPU CUDA processing and the perforations and keycode and grain are sharp and are completely steady in the scan.

The issue in camera also accounts for the lack of overall sharpness in the image as there is actually a very slight double image recorded to the film.

 

10 hours ago, Simon Wyss said:

Thanks for the elucidation, I am no expert with electronics.

The only failure left possible is film movement along the optical axis which implies the film pulling the pressure plate back. From what I see on the video the film is ripped off position by a too short lower loop during the last part of exposure.

I'm guessing its likely some sort of mechanical issue with the pressure plate on the magazine in question, I loaded the magazines myself on the footage i just sent off - they seem fairly idiot proof as far as getting the correct loop size goes so I really doubt it's that... we'll see what happens 

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4 hours ago, Kyle Perritt said:

 

I'm guessing its likely some sort of mechanical issue with the pressure plate on the magazine in question, I loaded the magazines myself on the footage i just sent off - they seem fairly idiot proof as far as getting the correct loop size goes so I really doubt it's that... we'll see what happens 

I am thinking pressure plate too, have you tried checking if it is stuck or if the spring tension on the plate(s) is ok?

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2 hours ago, Robert Houllahan said:

I am thinking pressure plate too, have you tried checking if it is stuck or if the spring tension on the plate(s) is ok?

It felt normal, but I'm just going to try and get it all serviced. Seems to be very overdue

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34 minutes ago, Kyle Perritt said:

It felt normal, but I'm just going to try and get it all serviced. Seems to be very overdue

Yeah these are mechanical machines.

It may also be that mag pressure plate was stuck in some way and running film through it loosened it but a tech look through is a good idea.

 

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