Loading Arri SR Mags.

[Tim Carroll]

We will be using an Arri SR1 for an upcoming production. Was wondering if anyone has any advice on loading the mags. Got the Jon Fauer book, which should be a big help, but have heard from a few folks that the book does not cover all the aspects and potential loading problems with the mags.

 

Any and all advice would be appreciated.

 

Thanks,

-Tim

[Guest oscar]

Hi Tim:

Arri SR mags are usually very much trouble free. Just notice when you are going to place the mag on the camera body that film is going trough the guide channels , the film upper and lower loops most be centered, and after placing the mag on body always check that it is properly seated and locked, never forget to put the upper silver lock on the Lock position and test that it is really "locked" by moving gently the mag, dont forget to press the test red button on left ( operator side ) just side to the trigger for the camera mechanism to properly engage film, when you are working on the take feed side, dont forget to push the counter roller arm towards film and check that core lock is on, I usually fold film ( about an inch) over itself to make it twice double thick to lock it on the take up side and then have a couple of rounds around take up core ( usually five ) and then lock the arm into position. Be sure to double check that Feed up side mag door is well locked and closed before opening changing tent, and check on edges of door to see that the door is not "bitting" any film edge, it is easier to guide film trough the feed sprockets if you do that with film roll outside mag, just be careful that doesn''t get loose keep it thight with your left index finger and pressure with the palm of your hand. Good luck.

All the best

Oscar

[Mitch Gross]

I just taught a whole troop of students how to do this. First off, tear the film across a perf; this way it will more easily engage the sprocket wheel. Some people like to load the film through the pass-thru to the sprocket wheel before putting it on the core adapter. I diagree--there's plenty of room to send the film into that hole after mounting it on the core adapter. Just roll the film end in your finger a bit to curve it the opposite way it normally curves--this will aid you in getting it into the slot. Push gently until you make contact with with sprocket wheel. If you tore the film well you should be able to simply push it right onto the wheel, but if you meet some resistance simply reach underneath to the main drive gear (the gear wheel that interfaces with the camera body) and wiggle it a bit until the film properly engages with the sprocket wheel. Push through so there's plenty coming out the front of the camera--at least a foot. Engage the tensioning roller on the feed side for the footage counter, and be sure that it is wraped around the film and not riding on an edge. Also be sure that the film and core are fully pressed down onto the core adapter. Close the feed side door and secure it. I like to cover it with a bit of camera tape for safety.

 

Now you can work outside of the changing bag. Pull the film around the front of the mag and underneath to the line scribed on the base. Open the take-up side door and hold the main drive gear in place. I like to again curve the end of the film back now so that it will load straight into the sprocket wheel. Push the film into the housing on the front of the mag below the main drive gear (the opposing corner to where it came out from the feed side) and push until you feel resistance. Make sure you have held the main drive gear in place so as to maintain the proper length for your loop. You should again be able to feed the film right onto the sprocket wheel, but if not then slightly rock the main drive gear until the film engages. Now feed through into the take-up side. If you have a collapsable core (metal ring core with a clip built in), feed the film into it and close the clip. If you have a core adapter as on the feed side then mount a 2" (small) plastic core, fold over a single frame of film and push the double layer into the core's slot. Wind the core a few times until the tension begins to tighten. Engage the tensioning lever making sure it wraps around the film. This lever helps the film take-up in a tight wind so that it is easier to download. Close the take-up side and put some tape over the latch.

 

Note--those core adapters costs $50 to replace, and it can be very easy to send then off to the lab by mistake, where you'll never hear from them again. Also, if you have a collapsable core, I like to insert a standard 2" core inside the space they leave behind so that the film doesn't unwind into that space (really annoying to the lab guys).

 

Other notes--Although it can sound very satisfying, resist the erge to slap the mags into place, as this can burr and damage the main drive gear and cause a lot of camera noise. Also, there is a small spring-loaded flap on the camera body where the top of the mag engages. If you go in at a slight angle this flap may not lower, in which case you could fog the entire roll of film and not know it until viewing the footage. If you are using on-board batteries be very gentle with the battery mount adaptor. The little screw that mounts it should always be snugged in tight or you will stress the 4-pin XLR connector. You have no idea how many of these I've seen broken over the years. Be very careful mounting and removing the battery and actually put a couple of fingers on the adaptor mount to relieve some of the pressure. When swinging the battery up into place to hold to the mag, do so gently so as not to crack the plastic housing of the battery.

 

Hope this helps.