On Set Backup of Video files

[Eric Coughlin]

I was wondering if high end shows and movies have on set backups being recorded to Odysseys, Atomos, etc. Arri, the most popular cameras at the high end, do not have any dual record feature, so if you're shooting at say a million dollars per production day, it seems a big risk to rely on just one memory card for everything. I've certainly had issues with CFast cards, which the Super35 Alexa Mini shoots on. And there are so many other risks aside from card failure - loss of card, theft, accidental damage, file corruption, accidental formatting, etc. I get that having a high end DIT reduces these risks, but the risks are still present.

Watching behind-the-scenes videos I don't tend to see external recorders mounted to the cameras. Perhaps the Teradeks are recording backups? I believe Teredeks compress the footage quite a bit so those would be lower quality backups at best. Or are there typically not backups while recording?

 

[Run&Gun]

Teradek Bolt series transmitters and receivers(the ones everyone uses) don't record and I always thought they advertised them(or gave the impression) as un-compressed. At least one of their "WiFi/IP" transmitters did/does have the ability to record, though.

Personally, I like the idea of redundancy, especially on extremely important things, but there are really few cameras that have that ability built-in. Out of the three camera models that I currently use on a regular basis(that I own), only one has the built-in capability to do redundant/simultaneous recording without anything else attached and it's actually the cheapest camera of the three. And it uses of-the-shelf consumer media. A C300. The consumer media may be a reason why dual-slot recording is offered, though. I'm not going to lie, I've lost count of the times I've put a CF card in a C300 and wondered if it was going to work. And there have been times that, sure enough, it didn't. This has been brought up before and I believe the argument from a manufacturer rep was that the chances of camera media failure are so small, that it's not worth it. Of course, tell that to anyone who has had a failure or otherwise lost footage, when a redundant recording would have more than likely saved the day. And I have seen/heard of way too many CFast failures that it is surprising that Arri actually put their eggs in that basket. The card interface is pretty damn finicky and delicate. From where I sit, P2 has been the absolute most bulletproof solid state media I have ever used. SxS is pretty solid, too, but ridiculously priced. Kind of surprised Arri didn't stick with them for the Amira and Mini.

If I was 'camera king', one of my decrees would be every camera has two identical media slots with the ability to 'dual-slot'/simultaneously record in at least real-time frame rates, preferably all frame rates(real-time and over & under cranking). And for cameras that use something like a CODEX for RAW, that the internal camera media slot can at-least record a full-rez log copy. I've shot 4K RAW on my F55 with a Sony R5 and R7 and while I could simultaneously roll in-camera, I could only record a 2K copy to the in-camera media. Better than nothing IF something happened to the RAW 4K footage, but 4K would have been better.

 

[Eric Coughlin]

Yeah, CFast is junk. I wonder how reliable CFast Express will be. At least the Mini LF switched to Codex which should be more reliable.

I thought the Sony F55 had internal dual record as well as proxy record. As far as I know, the Varicam 35, Sony Venice, and Canon C700 all have dual record, while Arri and Red do not. I guess maybe you do make a point that none of these cameras have dual record in their highest quality mode, such as 4K RAW to Codex (and whatever recorder the Venice uses). I'd imagine each of them could still record the lower quality to the internal cards at the same time as the docked on recorder is recording, but I'm not familiar with if that's the case. The C500 has dual record, but it's not uncompressed RAW. I think Blackmagic can dual record uncompressed RAW.


I wasn't referring to the actual Teredek doing the recording; I meant it transmitting to a recorder.

Looking at the top end Teredek (https://teradek.com/pages/bolt4k), I see...

10 bit 4:2:2 at 4K. And the 4K Teredek's just came out a bit over a year ago, so before that it was just 1080 available.

From what I'm seeing the Arri transmitter that comes built in the Alexa LF (full size) and Alexa SXT is 1080p at 10 bit; I did not see the color space specs but I'd guess 4:2:2 as well.

Any high end camera on a big movie is going to be shooting beyond those specs. In Arri's case, I believe they can't even output via SDI to as high of quality as their internal recording is capable of.


That said, 4K 10 bit 4:2:2 could perhaps be good enough for a big budget movie as backup rather than re-shooting footage just to get back to 4-8K RAW. What I'm wondering is, is recording from the wireless transmitters a standard procedure on big budget productions or are they just relying on the in camera media.

 

[Run&Gun]

The F55 does have dual card slots, but does not posses the ability to dual-slot record under normal circumstances. Only when an R5 or R7 RAW recorder is attached(only one internal slot records). I'm pretty sure the proxy recording of the 55 is recorded onto the same card as the primary file(don't quote me on that, though). The Venice behaves in the same way. It can record with the R7 and in-camera simultaneously, but not just an in-camera dual-slot redundant recording(like the C300 and other Canon's) The V35 does have, what I believe is a pretty unique ability, to record high frame rate and real-time, simultaneously.

Re: Teradek. Gotcha, I thought you were asking if they actually possessed the ability to record.

 

[captslomo]

Yes, the F55 can record 4K files and proxies onto the same card at the same time. It cannot, however, dual slot record full rez files. (to the best of my knowledge)

 

[Alex H.]

Shooting on film has no backup. Still carries risk of damage, theft, loss... though damage from light exposure is different from data errors. But it’s worked for over a century.

The need for dual recording doesn’t phase me on commercial and narrative production just because the risk for errors seems to be much lower in an environment of shorter takes. If the production is covering something like reality, or a live presentation, where recording can run hours at a time without stopping, then I’m more inclined to have that safety net of dual slot recording. But as you mentioned, having a good DIT on set to back up cards as soon as they come out of the camera greatly minimizes potential for disaster.

A lot of the commercial/corporate stuff I work on around here is shot on RED. The features I’ve worked were shot on Alexa Mini or Sony Venice (though Venice does have dual slots, one for full-rez and one for proxy). The competition show I work on that runs nearly-constant recording across 12- to 14-hour days shoots on the FS7 (four cameras). Different tools for different jobs.

 

[Eric Coughlin]

How often are DITs dumping cards on big budget productions? Every 30 minutes, two hours, four hours, etc.?


Tommy Wiseau shot The Room on film (Arriflex 35 BL4) and digital (Panasonic HDX-900) at the same time, which gave him an on-set backup as well as having the choice in post of if they preferred film or digital. I honestly don't know why this method never caught on.

 

[Alex H.]

How often are DITs dumping cards on big budget productions? Every 30 minutes, two hours, four hours, etc.?

As often as cards fill up, and I don’t think that has any correlation to the budget of the production. If there’s a DIT on set, cards are dumped as they are filled. I’ve worked productions where the DIT had a shifted work day as well, coming in an hour or so after general crew call and staying an hour or so after wrap.

I’m not sure I’d look to Tommy Wiseau as any kind of filmmaking visionary. That production wasted SO much money. He thought he was cutting-edge for being the first director to shoot on both formats simultaneously, but that just wasted more money because it took a second crew to run the second camera. And none of the digital (720p24) footage was used in the end. He also didn’t grasp the differences between the two formats.

 

[Eric Coughlin]

That sounds a bit random, then. In terms of risk management, depending on amount of footage being shot, some card capacities can last a whole day of shooting, or multiple days. Of course the DIT should also be checking the shots to make sure all looks good, nothing needs to be re-shot for other technical reasons such as being out of focus, etc. When I work with a DIT, which is not very commonly, we probably dump around 2-4 times per day on average, regardless of the size of the memory cards.

I’m not sure I’d look to Tommy Wiseau as any kind of filmmaking visionary.

What an absurd thing to say. I suppose you also don't consider Steven Spielberg and Alan Smithee to be visionary filmmakers.

 

[CharlesPapert]

I have never seen a secondary backup recorder in use that I can remember. As Alex said, film didn't have a backup. The percentage of footage lost to corruption or mismanagement is low enough that I've yet to see a mandate for backups.

That said, I have myself experienced a number of times shooting both film and digital where we have had to re-shoot because of lost footage--it was more common in film, and the early days of digital when we were still sorting it all out. We lost half a day's work on the very first day of shooting on Key & Peele because the KiPro Minis we were using to record from the F3's kept overheating and failing in the hot sun (to this day, "KiPro" is still a dirty word).

Loader/media manager error has become much less common with checksum software and duplicate drives. My first job on file based media had a disaster where the loader mislabeled files and dumped a bunch without backup--on two consecutive days (of a two day shoot)! His name is right up there with KiPro for me...!

There was a period when studios were wary of flash media and the bond companies wouldn't sign off on it. Remember that digital started as a tape based format, which was a hard piece of media vs the apparent volatility of a card. I was on the first movie that used a flash based onboard recorder with the Genesis--we had the only two mags in existence and after we shot each one, the loader would have to copy them over to the HDCAM deck in real time and that became the camera original.

Finally, on the notion of recording the transmitted signal...regardless of specs that indicate uncompressed signal, there is still processing going on in the transmitted image (the weaker the transmission, the more the image is compromised). Often the transmitted image has a viewing LUT on it as well. All this adds up to a pretty questionable backup source. And adding an outboard recorder to a camera is extra bulk and weight particular for gimbal/stabilizer/handheld applications. It is a shame that the manufacturers have veered away from outboard recorders without integrated monitors, as I think there could probably be one now that is the size of an audio receiver, but I'm assuming that the market for such a thing is too limited to justify.