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The right loop.


Carl Nenzen Loven

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Hey everyone,

This is really messing with me and I am trying to find the solution to this.

I have shot with both Aaton LTR, and the Arriflex SR, SR2's and SR 3's.

Now when I was looking for a camera to buy, it was to be a sound sync one, and naturally people suggested the ACL. When I look at the manual it says in the best of worlds is just under 32 db. Now I have shot on the Sr2 recently and the only real noise that we hear is the daylight spool spinning. And I know that the loop really matters here so please, if anyone could show me a proper one.

Also if anyone has a video of their camera loaded and the sound, I would be happy to hear how it should sound :)

C

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The ACL II specs I have give 28db. The three ACL IIs that I've scratch tested were all noisier than the old ACL I that I used to use. That camera had done an enormous amout of work before I got it, but was regularly serviced by an experienced guy, and only ever ran at 24/25 fps.

 

The things that I think affect the noise are...(me being no camera tech, just from using and familiarity)

 

- Fresh film was normally quieter. I assumed that the tech used fresh film when tuning the camera, still dimensionally accurate and lubricated.

- A service tech with the right experience.

- A properly serviced camera.

- Care with loops.

 

With the mag off the camera should be quiet, just the whisle of the mirror and a very faint tick tick from the movement. If not it needs the doctor.

 

The loops can be set as they say in the manuals. Check that 13 perfs are visible when you pull the fillm out the front. There should be a slightly bigger loop at the bottom than the top. If one is careless setting the loops and mounting the mag then the loops can shift towards the top or bottom and be a bit noisier. You can actually put the perf in a precise place on the pressure pad, inch the sprocket drive, check loop sizes, and position the camera claw so it will pick up a perf almost straight away.

 

Sometimes when you mount a mag the mag drive shaft does not click straight in, which can mean that the loops go a little off. It's a good practice if one is new to ACL or if one has temperamental mags, to take the take up door off after mounting the mag and while running, check the loop sizes. Certainly I would do this when scratch testing and familiarising oneself with the camera and mags.

 

On a properly serviced camera I found all the noise came out the back, where the nose of the mag fitted to the camera. If you use a soft barney it dissapears. I used an Arri BL barney that was just flopped on top without being wrapped at the front and it worked great.

 

Final thought. To compare the different cameras for noise, they all need to be properly serviced, using the same fresh film, with the same environment and background noise. The type of noise that the different cameras make will not be the same. Get a sound recordist involved with your noise tests. Talk to old sound recordists who have worked near these cameras years ago.

 

If you do do some testing, try and compare the earlier mags with the single piece pressure plate, to the tater ones with the centre pressure plate. Also, the sound deadening is not the same on all mags. Did all or only some have sheet lead?

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The ACL II specs I have give 28db. The three ACL IIs that I've scratch tested were all noisier than the old ACL I that I used to use. That camera had done an enormous amout of work before I got it, but was regularly serviced by an experienced guy, and only ever ran at 24/25 fps.

 

The things that I think affect the noise are...(me being no camera tech, just from using and familiarity)

 

- Fresh film was normally quieter. I assumed that the tech used fresh film when tuning the camera, still dimensionally accurate and lubricated.

- A service tech with the right experience.

- A properly serviced camera.

- Care with loops.

 

With the mag off the camera should be quiet, just the whisle of the mirror and a very faint tick tick from the movement. If not it needs the doctor.

 

The loops can be set as they say in the manuals. Check that 13 perfs are visible when you pull the fillm out the front. There should be a slightly bigger loop at the bottom than the top. If one is careless setting the loops and mounting the mag then the loops can shift towards the top or bottom and be a bit noisier. You can actually put the perf in a precise place on the pressure pad, inch the sprocket drive, check loop sizes, and position the camera claw so it will pick up a perf almost straight away.

 

Sometimes when you mount a mag the mag drive shaft does not click straight in, which can mean that the loops go a little off. It's a good practice if one is new to ACL or if one has temperamental mags, to take the take up door off after mounting the mag and while running, check the loop sizes. Certainly I would do this when scratch testing and familiarising oneself with the camera and mags.

 

On a properly serviced camera I found all the noise came out the back, where the nose of the mag fitted to the camera. If you use a soft barney it dissapears. I used an Arri BL barney that was just flopped on top without being wrapped at the front and it worked great.

 

Final thought. To compare the different cameras for noise, they all need to be properly serviced, using the same fresh film, with the same environment and background noise. The type of noise that the different cameras make will not be the same. Get a sound recordist involved with your noise tests. Talk to old sound recordists who have worked near these cameras years ago.

 

If you do do some testing, try and compare the earlier mags with the single piece pressure plate, to the tater ones with the centre pressure plate. Also, the sound deadening is not the same on all mags. Did all or only some have sheet lead?

Thanks for such a complete post Gregg.

 

I just learnt how to load the Arriflex BL-series, and the 35 III, and the loops there are essential when it comes to running silent. Now I know my ACL is in need of a CLA, but I wonder how much that can “fix” in this scenario, and what is actually just the lowest noise possible.

 

I considered a Barney as well, but finding a place that makes one seems a bit hard.

 

Also, I only use lenses on adapters, how much do you imagine that adds to it? When I did my last test it was without lens as well, maybe the weight blocks some sound as well?

 

C

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Please read carefully. The noise is not just down to the design, the service skill is important, I always thought anyway. If you need really quiet, my guess is get an XTR or SR3 and have it serviced by a a guy who knows how to make them quiet. Or just throw a barney over your ACL. Barneys come up on eBay now and again. Getting a pro made one is too expensive maybe. I don't believe it needs to fit ACL carefully, just drape over the back.

 

Somewhere, someone has an unused barney on the shelf just waiting for you.

 

It's not meaningfull to do noise tests without a lens, though I supose it tells one something. Should we not use the same lens for each camera?

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Talk with Bernie at Super16 Inc. he serviced my ACL and now you can barely hear it running unless you are holding it against your head on your shoulder. I've even had my actors ask if it's really running. It should be about as quiet a camera as you'll see, certainly for the lower cost side of things.

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  • 10 months later...

Talk with Bernie at Super16 Inc. he serviced my ACL and now you can barely hear it running unless you are holding it against your head on your shoulder. I've even had my actors ask if it's really running. It should be about as quiet a camera as you'll see, certainly for the lower cost side of things.

 

Do you happen to have any video of this camera running?

 

I am still now sure what I am doing wrong.

 

C

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camera noise also comes out of the front/lens of the camera too.. an optical flat in your mattbox can help.. as I remember Aaton was always the less noisy camera .. some SR,s would sound like a tractor.. barney is your friend .. get one custom made up.. I doubt anyone is making them these days.. but should be easy enough to get custom made..

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  • 2 weeks later...

camera noise also comes out of the front/lens of the camera too.. an optical flat in your mattbox can help.. as I remember Aaton was always the less noisy camera .. some SR,s would sound like a tractor.. barney is your friend .. get one custom made up.. I doubt anyone is making them these days.. but should be easy enough to get custom made..

I have already had a look for that.

 

None of the contacts I know of make them anymore.

 

I have even posted on this forum.

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Not to upset Robin, who is a cool guy and always ready with some good natured wit (humour)......But .....

 

....different cameras make different sorts of noise. Maybe Arri did/do throw a lot out the front, but ACL, the only problems I ever had were coming out the back, somehow where the mag seats into the body, or may be from the front of the mag itself where the loops are. But this was very easy to solve. I had/have a pro made barney for a 16BL and I just dropped it over the top to cover the back, with the front of the body and lens port not being sealed up they way one might assume they should be. It didn't fit perfectly but it worked perfectly.

 

So an improvised barney or a barney designed for another camera can work OK. You don't need to go get a proper custom made barney, but wait and one will turn up eventually. Or you could have a clever friend make one. The 16BL one was leather exterior, corduroy lining and I don't know what the interior padding was. Carl, I can send you a couple of pictures if that helps....maybe an old 16BL one is easier to find. If there is some lack of glamour or social acceptability to not having a properly fitting barney, I say....forgettaboutit. I have a pro made fitting ACL barney here and it is slow to fit, slows the mag changes and has no advantage. But I haven't used that one in anger....

 

Carl, review any posts that give ideas on what can give noise or reduce it. A tech who really knows those cameras helps. I think the pitch and friction of the stock changes over time. Noise varies with stock. Some stock may have more emulsion build up that may be affecting noise. The pitch of the camera movement. The type of sound deadening in your actual mags. The plain vs centre pressure plate mags issue......and so on....Some of these issues you can experiment with and improve the noise easily...

 

Just remember that for a legitimate comparison you normally can change only one thing....If that sounds too arcane I can explain...

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  • 5 months later...

Hi, I am having issues with my 120m magazine, the loop never stays and the film gets messed up after a few seconds. When I wind the motor by hand the problem does not occur. The faster the framerates the sooner the loop is gone. Any ideas? (I made the loop like in the manual, I made it like in the tutorials, I tried it with bigger loops and smaller ones... nothing works)

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I saw it loose it's loop quick under power. There must be someone in Berlin qualified to diagnose this. These are the times when you have an excuse to walk through their front door and ask for help on an interesting technical problem. Just do it. Some rigorous searching first on who/where may be the best place to ask/look.

 

Other inexpensive ways to diagnose this: do yo have access to another magazine..? If the problem is to do with the magazine, the drive, sprocket, little retainer rollers for the drive sprocket, or the pressure plate, then putting on a good magazine will logically separate that stream of possible problems.

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Since your bottom loop fails first, it indicates to me a gate transport issue. Somehow the pull down claw is missing perfs at-speed and allowing the lower loop to fail, thereby pulling the film through the gate and rapidly collapsing the upper loop.

 

You need to have the pulldown claw and gate pressure examined on this camera/magazine combo.

 

Do you have another mag to test it with?

 

If it happens on more than one magazine, it is probably that your mag to camera body tolerances are incorrect and need to be adjusted.

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I see, yes that makes sense, I will try another mag soon.

 

I first thought it might be an issue on the feeder-side... may be the unwinding of the film does not happen as smooth as it should. May be that could explain why the loop is fine when winding it by hand and still kinda ok for a couple of secondes on really slow framerates and then messed up immediately with faster framerates?!

 

Anyways, so if my 60m mag will be fine then it must be something with the 120m mag I haveo here or is there then still a possibility that the body/ the claw has an issue?

Edited by lars preisser
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I see, yes that makes sense, I will try another mag soon.

 

I first thought it might be an issue on the feeder-side... may be the unwinding of the film does not happen as smooth as it should. May be that could explain why the loop is fine when winding it by hand and still kinda ok for a couple of secondes on really slow framerates and then messed up immediately with faster framerates?!

 

Anyways, so if my 60m mag will be fine then it must be something with the 120m mag I haveo here or is there then still a possibility that the body/ the claw has an issue?

 

Just speculating, but the pressure pad on this particular magazine might be slightly weak or out of adjustment. This would not allow sufficient "recovery" time (spring-back) to engage perforations "at-speed", but allow correct engagement at slower rates of feed.

 

If your 60M mag works fine, I would speculate that it's just that magazine, but if the camera has not been serviced in a long time, there could be other issues that only show up on the higher capacity magazine.

 

If the 60M mag works, try comparing the coupling mechanism between the mag and the body of the camera. Is one magazine looser than the other? Is there a lot of play or slop in the drive mechanism? In any event, it sounds like a service call would be in order.

 

There is an old saying that repairs are cheaper than reshooting...

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OK, I watched it again too and you're probably right; It's hard to judge exact timing from a youtube video.

 

I viewed it this time in full magnification and it appears your test footage is damaged prior to entering the gate. Watch the edge of the film above the feed sprocket and you'll see the damage pass through just before it hits the sprocket and into the gate where it looses the loop.

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I asked the previous owner too and he said it could also just be the film I used here which is an old fuji 8662 that has been in dry storage for like 10 years.

He suggested to put the film open in a darkchamber with around 80% humidity for 12 hours- sounds easy- let's hope that works.

Has anyone else had problems with old film on the Eclair or other cameras?

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Lars, you have another magazine but you have not tested with that...? Please do and let us know what happened.

 

I looked for the damaged stock in the video but couldn't see it. Testing the basic mechanical function of the camera/mag one can reuse film stock but it can't be damaged, overtly shrunken or shedding emulsion.

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Lars, you have another magazine but you have not tested with that...? Please do and let us know what happened.

 

I looked for the damaged stock in the video but couldn't see it. Testing the basic mechanical function of the camera/mag one can reuse film stock but it can't be damaged, overtly shrunken or shedding emulsion.

 

I will test the other magzine on the weekend, don't have it with me at the moment. No its fine material but it might be shrunken so the perforation is not accurate anymore and causes all the trouble.

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I asked the previous owner too and he said it could also just be the film I used here which is an old fuji 8662 that has been in dry storage for like 10 years.

He suggested to put the film open in a darkchamber with around 80% humidity for 12 hours- sounds easy- let's hope that works.

Has anyone else had problems with old film on the Eclair or other cameras?

 

Lars, that was a significant omission, that the stock is very old and improperly stored. The assumption is always that you are using new stock to test a camera for operation.

 

We have found that shrinkage over 0.7% (linear) in 16mm will be destroyed on a Steenbeck flatbed viewer.

 

Film shrinks in non-uniform ways over time. You are courting disaster using this stock for anything but just experimentation. Your feed sprocket is probably damaging perforations on shrunken areas of the stock just prior to entering the gate and once the damaged section (now with "lowered" perforation bottom edges) passes through the gate, the claw misses the next non-deformed perforation and you loose the loop.

 

 

Test the camera with a bit of new stock; I'll bet its fine.

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Hi, so I tried my 60m mag now with the old film and it works fine.

So it seems to be the 120m mag that is the problem at last.

I noticed that when I try to pull the film on the take up side there is quite a restistance when doing so on the 120m mag

while on the 60m mag it is very smooth.

Edited by lars preisser
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We have found that shrinkage over 0.7% (linear) in 16mm will be destroyed on a Steenbeck flatbed viewer.

 

Viewer-editors are not film friendly, they were made for synch and editorial work to dailies/rushes,

repeatable copies of picture and sound. Never must one place originals on these apparatuses.

The intermittent sprocket Moviola is a little better in that respect. True, Steenbeck delivered sprockets

fitting shrunken stock at some point of time but strains are still too high. Originals belong in canisters

far away from cutting rooms.

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