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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Issue with drop frames when recording in a loud environment

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Digital Upstart

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Hello,

We've had some issues with drop frames when shooting in a loud environment.

We were shooting 2K at 120FPS at the FA Cup Semi-Finals at Wembley stadium this weekend (big soccer game in the UK) on a 320GB Red Drive.

The issue we saw when playing back the footage is that when a team scored and the croud noise erupted, the camera dropped frames giving us a grey and sometimes green screen. After a few seconds the image would be back and we had unfortunately missed the team celebration, which is what we needed to be shooting.

One time during shooting we saw "codec error" just before the camera dropped frames, but only once did we see a warning. We have dropped frames everytime the crowd noise became loud, meaning we have great footage until something important happened.

Has this been an issue in the past? And how can it be prevented? The company we were doing it for are not convinced that the camera will be able to handle the Final at the end of May :(
 
So there isn't a solution?

We were thinking about using the longer drive cable that is available and having the drive housed in something to soak up the vibration (like a pelican case with foam or a box with, erm, fabric or something). Does anyone have any expeirence of this?
 
Digital Upstart said:
So there isn't a solution?

We were thinking about using the longer drive cable that is available and having the drive housed in something to soak up the vibration (like a pelican case with foam or a box with, erm, fabric or something). Does anyone have any expeirence of this?
Click to expand...

I think something like that would probably solve it. I remember one guy put a raid in a pillow for moving car shots. I shot a concert to red raid as a test and the drive did really well about 98% of the time at a very loud rock show and I was right next to the stage woofers. When the crowd cheered I'd get dropped frames. Weird.
 
Digital Upstart,

In our crews experience, mounting the RED Drive with an Element Technica Shock Mount and Speedy Clamp solves that situation in all but the most extreme noise/vibration level situations. We've used that setup in multiple very loud concerts, sports events, and high vibration situations (helicopters, boats, etc.), without any dropped frames.

That said, even with that setup, if you're standing right in front of a 180 db output am or have the rig strapped to a boulder-bounding 4x4, you may still experience some dropped frames.

Its an affordable solution...
 
You should seriously consider this:
http://www.elementtechnica.com/products/view.php?p=40

I have been shooting from an helicopter without a single drop frame, if this doesn't work then then the RED Ram is your only option, expensive but better than loosing a client.

Emmanuel
 
For a simple explanation of what is happening, look here:

Unusual_disk_latency

Scroll down the page for a visual demonstration, it shows exactly the situation you were encountering
 
Joel Kaye said:
I think something like that would probably solve it. I remember one guy put a raid in a pillow for moving car shots.
Click to expand...

I regularly shoot dolly/drive-by shots with one of my REDs strapped onto the roof of my SUV. I use a RED Drive/ ET Shock Mount/ET Speedy Clamp mounting, set the camera on one of my Cine Saddles, strap the whole seup down onto the roof inside the luggage rack using motorcycle ties, run a 10' RED LCD cable and 10' Origo start/stop switch from the camera through the passenger side window or sunroof, and have someone else drive while I sit in the comfort of the passenger seat, watch the potential shots go by on the RED LCD in my left hand, and simply hit the Origo button in my right hand to record or stop.

The combination of the ET Shock Mount, and the Cine Saddle, with its vibration damping interior beads, eliminates any dropped frames - even on very rough roads - and the shots are surprisingly smooth. I put the camera inside a trash bag to keep the dust/bugs off it, with just the end of the lens barrel sticking out, with a 35mm stills lens using a screw on ND filter as needed.

I guess I could also get the long RED Drive cable and put the drive in the seat next to me, but I already own the shock mount and long LCD and Origo cables, plus, that way its easy to re-position the rig, and simply pull it off the roof and use the camera/Cine Saddle setup quickly on a rock or fence post for stationary shots along the way.

These are low-tech solutions that work well...:-)
 
Emmanuel Cambier said:
Hey Steve you beat me to it, damn you :)

Emmanuel
Click to expand...

I had a feeling someone else would post the ET Shock Mount solution pretty quickly...so I typed as fast as I could :-)

-----------

Hey - there should be good waves this time of the year in the southwest of France where you live...catch a few for me! I need to visit there again sometime soon...
 
The ET solution, while effective for low frequency mechanical vibration, might not be as effective for wide spectrum (crowd) noise. (See my previous post...)
 
Maybe a Red Drive Blimp is needed....
 
Todd T said:
The ET solution, while effective for low frequency mechanical vibration, might not be as effective for wide spectrum (crowd) noise. (See my previous post...)
Click to expand...

It has been very effective for us in crowd noise situations. Recent example: I was DP for a 10-RED camera production last month featuring the rock band Journey in concert in Manila. We had all cameras use ET Shock Mounts, the crowd and sound levels were high - and we experienced no dropped frames whatsoever from any of the cameras. Same result in multiple huge crowd sports events.

There's another thread active here from another crew that did experience some dropped frames in a music concert production while using the ET shock mount/RED Drive combo, but it seems to be isolated to cameras that were right in front of drum sets and/or amplifier stacks. Crowd noise didn't seem to be the cause of their dropped frames though. Their additional solution, beyond the shock mounts, was to also wrap the drive/shock mount setups in small towels, which seem to absorb sound vibrations.
 
my friends happened the same drop frame when he shooting Macao grand prix last year November, the way only he can use CF 8G or 16G for shooting, not red drive.
 
The issue is that we need to shoot at 120FPS and a game is 90mins long, plus extra time, and also shooting before the game, during half time and celebrations after. Even vox pops before and after. CF cards are not an option because of the framerate limitation, and the Solid State drive from Red is too pricey...
 
The ET shock mounts work great. But there are times when even they aren't enough. You can try protecting the drive inside foam or other things to shield from noise / vibrations. Other than that, you will probably have to go with CF card or RED RAM.

If the shock mounts won't do it or you need an immediate solution, try wrapping the drive in bubble-wrap with some foam or heavy blanket / coat on the outside to help muffle some of the additional noise. Be wary of static when you do this.

As for fixing any footage already shot, you can't. The dropped frames are just that. Frames that were dropped and never recorded due to the drive mechanism skipping from excessive vibration. All you can do is trim out the bad frames and try to blend in post.
 
I have produced/shot several multicam large venue rock´n roll shows on the RED One, and we have had luck using both the Element Technica mount as well as wrapping our drives in several layers of black molton (beware of it getting too hot though - which hasn´t happened to us yet) We usually keep the ends open, to allow air to circulate.

At the most extreme we had our camera mounted on a moviebird crane two meters (6 feet) from the main speakers at a LOUD rock concert, and during two hours + we had a total of 48 dropped frames (2 seconds), in one instance, which to me was acceptable - escpecially concidering the constant hammering the drive had to endure from the speakers AND if we had wrapped it in even more molton I am pretty sure we would have had 0 dropped frames.

If you have the time/opportunity test it beforehand.

ET seems to work in most cases, although I am a bit worried that the surface of the disk could catch enough vibrations even while on the ET mount.

The low budget solution is to loosly wrap your drive in molton/towels whatever fabric you have, it will stop the sound/vibrations and protect your data.

Good luck!
 
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