SR3a HS Mag in normal cam?

Colin Theys · April 22, 2005

Hey,

We just picked up a bunch of equipment for a film this weekend and the rental place was having some issues with understaffing and somehow we ended up with one of the wrong mags. :/ We're shooting with an Arri SR3 advanced and we got one normal mag and one high speed mag by accident. Does anyone know if we can use it with the normal camera? It seems pretty much the same except that it sayd HS Timecode on the side and the wheel moves a little more easily... We don't want to do any speed manipulation, shooting at 24fps. maybe one scene at 16, but we can use the other mag for that scene.

Thanks if anyone know the answer.

-Colin Theys

Rik Andino · April 22, 2005

Don't worry it's not a problem HS mags are okay for regular cameras.

Unless of course you press the SuperSpeed button :) (just kidding)

Good Luck

Edited April 22, 2005 by Rik Andino

Colin Theys · April 23, 2005

Don't worry it's not a problem HS mags are okay for regular cameras.

Unless of course you press the SuperSpeed button :) (just kidding)

Good Luck

<{POST_SNAPBACK}>

Thanks Rik. We ended up having to use that mag today. We really got screwed over by the rental company. Our other (normal) mag ate the film because it stopped spooling on the takeup side after only 3 feet. grrr. The highspeed seemed to work fine, expect that it wouldn't record timecode. But I suppose that's alright, since the DAT and mic they gave us didn't work either! (the only thing I didn't test when we rented because nobody at the place knew how to run the DAT and the sound guy didn't come with me to pick up.) I sure hope it worked! :unsure: (pretty sure it did though.)

Thanks again,

-Colin

PS. It'a alright if you put it in superspeed. You just can't go to plaid. :blink:

Edited April 23, 2005 by ColinTheys

Brent J. Craig · April 23, 2005

...We really got screwed over by the rental company...

<{POST_SNAPBACK}>

How experienced are you folks with using this gear? The only time I have ever seen an SR mag jam was when it was improperly loaded. There are only a few things you can do wrong: 1. winding the film on the takeup the wrong way; 2. not firmly attaching the film end to the takeup core; or 3. not seating the mag properly on the camera so the mag gear isn't meshing. Since the takeup is driven directly by a gear, it pretty much can't just stop taking up.

I would be very careful about blaming the rental house for what could very well be lack of skill on your crew's part. A good relationship with your rental house is worth it's weight in gold and if you treat them right you will never regret it! (Right Mike, Jerry, Jan?)

Edited April 23, 2005 by Brent J. Craig

timHealy · April 23, 2005

I have a High Speed SR and there are other things that may go wrong especially if the belts are too tight or too loose.

The main difference between a HS mag and a normal mag is the pressure plate. The high speed mag has a spring loaded floating type plate for the high speed work. And a normal mag plate is fixed.

Many will say you can use the two interchagably as long as you don't use a normal mag on a high speed body for frame rates of 75 fps or higher. I have done this and vice versa and 99% of the time things were ok.

BUT I did have one job where something happened and focus was off, and when I brought my camera to Arri in Blauvelt to check things out, they recommended not interchanging mags. So do it at your own risk.

Tim

Stephen Williams · April 23, 2005

BUT I did have one job where something happened and focus was off, and when I brought my camera to Arri in Blauvelt to check things out, they recommended not interchanging mags. So do it at your own risk.

Tim

<{POST_SNAPBACK}>

Hi,

ASAIK the flange depth is different by about 10 microns, so with a wide lens , wide open you will be soft!

Stephen Williams DP

Zurich

www.stephenw.com

Colin Theys · April 24, 2005

How experienced are you folks with using this gear?

I'd say it's pretty safe to say I know the Arri mags very well. Well enough that we took it apart and fixed it today once we got the film out. I've been on a number of shoots SR cameras and know them pretty well. The connection between the pin driving the collapsible core and the rest of the mag was not properly connected inside the mag and promptly fell loose after enough film had been run onto it (more than we tested it with.) The mag was moving properly except for the take-up, which is why the film was being crammed into the take-up side without the spool turning. We used it today successfully, though it made a very disturbing noise for the first 50 feet or so...

I don't want to name any names because I'm sure this was not typical, but (can you tell I'm mad at them?) some other evidence that they screwed up:

1. They didn't know how to operate the DAT (and neither did I,) so I couldn't test it there and sure enough when we got it back here and our sound guy looked at it, not only did the dat not work, but the mic didn't work at all with any equipment, including our replacement.

2. We called them and they told us they intentionally gave us the high speed mag.

3. They didn't have a few of the items we'd ordered (nearly a month in advance) and paid for. Simple things... like a mighty mole.

4. It took them 5 hours to prepare a simple list of equipment.

5. We asked them to put Tungsten bulbs in the kino-flo and though they're labled tungsten, they're definately not tungsten bulbs... they're not daylight either though...

6. The battery belt for the DAT doesn't hold a charge for more than a few takes.

7. They didn't give us the key to adjust the phase even though I asked specifically for it.

8. They had the camera set to super-16 when we had asked for standard. They said they would set it back when I insisted (the director is comitted,) but when I checked after they had "finished" the gate was still set for super 16. I asked why and they said "don't worry about it." Apparently they don't have the rail anymore. We made sure to shoot a frame for the printer, but it's not very professional if you ask me.

Anyway, I could go on, but I'm just ranting. The moral of the story is that I was way too trusting when I picked up the equipment. I thought we had a very good relationship with the rental house. We used the same stuff from the same place last year and they were great, so I was pretty relaxed about checking stuff out. ie I didn't actually look to see that the guy was telling the truth when he said he had just put the key to change the shutter angle in the camera case. (he didn't) And, of course, every single thing I didn't specificaly check for was either broken or missing. Also, the people there were very nice and our guy in charge of ordering equipment has a good relationship with them, maybe even going to work for them next year, so I didn't think they'd screw us over. Shows how wrong I was... From now on I will inspect everything down to the last screw and paint chip, which I should have done this time of course. Oh well, for not inspecing thoroughly enough I must accept partial blame.

Thanks for the help

-One very disappointed DP

with a wide lens , wide open you will be soft!

Uh oh! I just shot a scene with the HS mag tonight with a 9.5 lens open to a 2. I hope it won't be too noticable... :/

Edited April 24, 2005 by ColinTheys

Stephen Williams · April 24, 2005

with a wide lens , wide open you will be soft!

Uh oh! I just shot a scene with the HS mag tonight with a 9.5 lens open to a 2. I hope it won't be too noticable... :/

<{POST_SNAPBACK}>

Hi,

If you were shooting a close up it should be OK its further away the problem shows up.

Stephen

April 27, 2005

Uh oh! I just shot a scene with the HS mag tonight with a 9.5 lens open to a 2. I hope it won't be too noticable... :/

<{POST_SNAPBACK}>

Hi,

If you were shooting a close up it should be OK its further away the problem shows up.

Stephen

<{POST_SNAPBACK}>

Well,

you might end up with some focus problems as it was mentioned before. First off all there is the difference in focal distance between lens mount and film plane of about 3 to 4/10th but also the film gap is bigger if you use a HS mag because the pressure plate is not spring loaded to allow the film to move more freely on higher speeds. I hope everything works out fine but for future projects I would absolutely don't mix magazines either way.

Edited April 27, 2005 by alvitdk