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24 Frame Project Problem In Avid

 

Hey guys.

David Waldman here with a question I got from the post department on an effects heavy promo I shot on the F-900 yesterday. We downconverted at Laser Pacific and here's the email I got from the assistant editor...

Anyone know what happened and how we can rectify it?

Thanks,

David Waldman
Cinematographer


David Waldman wrote:

> We downconverted at Laser Pacific and here's the email I got from the assistant editor...Anyone know what happened and how we can rectify it?

I could, of course, mention that you should always use record run time code on HDCam to avoid any time code breaks, but I won't...

What the assistant editor is describing simply should not happen in a properly done downconversion, even if there are time code breaks. The downconverter should be "syncing" 24 and 30 frame codes based on even seconds, and resyncing every time there's a code jump, thus ensuring that "A" frames will always fall on 30 frame code numbers ending in 0 and 5. It sounds to me like the assistant is attempting to digitize the roll continuously, which essentially creates a problem on the Avid side - namely, that the pulldown removal is "locking" itself based on the first time code it encounters - then, when a break occurs, continuing the same pattern based on the tape control track rather than the time code. If this is the case, the least costly fix is for him/her to digitize each shot separately, starting each on a time code ending in either 0 or 5. Of course, if there is not enough pre-roll on each shot, the only other option is to do what he/she suggests - and clone the tape. What you do not want to do, however, is make a new HDCam tape, because by doing so you're going through two more HDCam codec passes -
not recommended. Better to go to D5.

Did I mention that you should always use record run time code on HDCam to avoid this problem?

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles


Thanks, Mike.

I as well, would always recommend shooting in Rec Run/REGEN mode, as we did on this shoot. I also did "rec returns" whenever we swapped batteries...I probably should have included these facts in my original post, lest I be taken for a complete neophyte...

The assistant did end up digitizing each take individually. Seems to have been a quick fix.

Thanks for the input.

David Waldman


Using record run in REGEN Mode is where laying down good Signal Starts.

However hitting the RET button on the ENG lenses or Assignables Lens Return

should be done not only at every battery change but also with every time you power down the camera or pop a tape out and put it back in.

We call it "Checking the Gate" and I gave that to my assistants so that they get in the habit of doing it.

Power up Check the Gate
Change batteries Check the Gate
"CUT" Moving on, Check the Gate

This way there should be absolutely NO breaks in Timecode, Control track, Picture, or Sound throughout the entire Tape. Its the least we can do to help our Post Brothers and Sisters. (its also nice to put Bars at the end of the shot tape as well just so they know there at the end especially when the tape is not totally FULL)

CU@NAB

B. Sean Fairburn SOC
Director of Photography
Castaic Ca


B. Sean Fairburn wrote :

Snip

>This way there should be absolutely NO breaks in Timecode, Control track, Picture, or Sound throughout the entire Tape. It’s the least we can do to help our Post Brothers and Sisters. (its also nice to put Bars at the end of the shot tape as well just so they know there at the end especially when the tape is not totally FULL)<

end snip.

Hear hear, I wish there were more people out there doing that as a standard part of their HD shoot workflow.

NAB it is..

J Schulte
Head of 2d systems
Condor Post
Amsterdam/London/Brussels/Berlin/Cape-Town/Pick One


> I could, of course, mention that you should always use record run time code on HDCam to avoid any time code breaks, but I won't...

There are certain types of projects that necessitate acquiring video in the field with "Free-Run" not "Record Run" time code:

Example: Live multiple camera events, such as concerts, where cameras in disparate locations are starting and stopping randomly over long periods of time.

On such projects, the editors must learn to "deal with" free run time code, and the necessary breaks in time code. I am told by those familiar with the Avid, that there are settings and techniques in the Avid (and other) system(s) to effectively deal with time code breaks, but some editors aren't often presented with multiple camera production techniques, and aren't familiar with the "workarounds".

Lew Comenetz
Video Engineer


> I could, of course, mention that you should always use record run time code on HDCam to avoid any time code breaks, but I won't...

This is not always possible, especially on multi-camera shoots where the client continually insists on checking playback from the various cameras.

The practical fact is, there will be breaks in the timecode. It should not because for endless angst and hand wringing. After all these years, you'd think Avids would be able to deal better with this, but they seem to handle the issue poorly, requiring lots of manual labor to fix it. Luckily, the manual labor usually comes from someone who is quite low on the salary and influence scale, otherwise this would have been fixed long ago.

And while we're on the subject, let me say how fed up I am taking the heat on set from the AD and Producer about the horrendously long pre-roll most Avid editing places demand. What winds up happening is that the AD refuses to cut tape, and the post place ends up with triple the footage to digitize, most of it useless, and the Producer is unhappy about paying for all the stock and extra digitizing time.

Bob Kertesz
BlueScreen LLC
http://www.bluescreen.com


Bob Kertesz writes:

> After all these years, you'd think Avids would be able to deal better with this, but they seem to handle the issue poorly

Sheesh...If iMovie can take timecode breaks in stride, why can't Avid?

And Final Cut pro needs only a few seconds of pre-roll, as a bare minimum.

> the horrendously long pre-roll most Avid editing places demand.

How long is "horrendously long?" More than 10 sec?

Dan Drasin
Producer/DP
Marin County, CA


> but in a doc situation, it would be a nightmare to do this every time you power down the camera. ..... But is this absolutely necessary? And is this just with HD, or is it the same with Beta?

It is the same with Beta, and every tape format I've ever worked with. However, the digital tape formats seem to take a little bit of extra time, since they take longer to power up/down than the old BetaSP cameras - lots more levels of menus to be read into memory!

Using the RET is not as bad as it may seem at first, even in a documentary situation - For one thing, it gives you the opportunity to do a regular check of your recording, which might otherwise not happen in a "run-and-gun" situation. I've caught many problems this way. (And actually saved a couple of producers money on insurance while on shoots out of the country - I've run into the question of "how often do you check the recording?" and can say with certainty that I do it at least once per tape, and at every power-up...)

In situations where you absolutely DON'T have time, it's not the end of the world to have a break in the recording - if it means missing a shot that you'll never be able to re-create, then go ahead and roll. Editors can find ways around the breaks in an emergency - and I've never had anyone complain in a situation like that. It's when there are several completely avoidable breaks in every tape that editors get cranky.

It's also less of a problem if you're in the habit of rolling several seconds at the head and tail of every shot... But of course if you've got time to do that, you've also got time to hit REC!

George Hupka
Director/DP
Downstream Pictures
Saskatoon, Canada


Dan Drasin wrote

> Sheesh... If iMovie can take timecode breaks in stride, why can't Avid?

Don't count on it's bigger brother though; the sound will go horribly out-of-synch if the timecode is dropped.

Cheers

Martin Heffels
filmmaker/dp/editor/filmschool techie
Sydney, Australia


Erin asks :

> Just how bad is the timecode going to be if you don't do this? When shooting in a quick moving documentary situation, it can be quite painful to wait the several seconds that pressing the RET button...

It's not that the time code is bad but that there will be a control track break in the tape and that makes editing software crazy.

Sometimes the machine cannot figure what's happening and starts racing FF to find the next break, etc.

It's more a matter of convenience for the editor, generally you don't loose the timecode sequence but the break can be time consuming in the post process.

I hit RET every time I power down or change batteries and I do it right after powering up, generally as I am shouldering the camera or putting it on the tripod. If you make a habit if doing it right after powering up, it really becomes easy and a matter of course and you loose zero time and your editor will love you for it.

It's very much like using a windup movie camera like a Filmo.

While you are composing your next shot, you wind the camera, then choose the lens, focus and set parallax. This all takes about a minute but if you don't do them, you really can't shoot... but if you do them instinctively, it becomes second nature.

It's multitasking at it's most basic!

Allen S. Facemire
DP/Director
SaltRun Productions,inc.
Atlanta


> > the horrendously long pre-roll most Avid editing places demand.

> How long is "horrendously long?" More than 10 sec?

8-10 seconds seems to be what they require. And 10 seconds is a LIFETIME after the AD yells "ROLL", especially when the sound guy yells "SOUND SPEED" half a second later.

And it's useless to point out that I actually have speed a second or two later, that this is for post. By lunch, the AD, the DP/operator, the Director and the talent are all just pissed off about having to wait.

Bob Kertesz
BlueScreen LLC


> 8-10 seconds seems to be what they require. And 10 seconds is a LIFETIME after the AD yells "ROLL", especially when the sound guy yells "SOUND SPEED" half a second later.

That's because the sound guy rolled when the AD called for everyone to settle and already had his 10 second pre-roll and thus speed when the AD called for a roll. Something camera operators should do as well.

Honestly, Bob, I think you're really exaggerating this whole issue.

It's just not that big a deal.

Mike Most
VFX Supervisor
IATSE Local 600
Los Angeles


> And while we're on the subject, let me say how fed up I am taking the heat on set from the AD and Producer about the horrendously long pre-roll most Avid editing places demand."

Well then, your place is either unique, or you have a much better grasp of how your NLE system works than most post places.

I have been repeatedly told (as recently as last week) that the post place needs "a minimum of 8-10 seconds of continuous timecode before the in-point" in order to capture correctly.

The capture aspect of NLE's appears to be the weakest part of the system, and this weakness is exacerbated by the fact that the captures are often left to be done overnight with no supervision by the least experienced person in the house, often using a rented deck of unknown quality which has not been set up by anyone.

How ridiculous is it after being in the market for many years - a supposedly "mature" technology - that an editing system would throw up because of a break in the timecode? In what other business would this level of technical incompetence in an expensive system be acceptable? Nothing seems to have been done about this in the last decade, because I keep hearing this stuff from post over and over; in fact, if anything, with more and more "editors", agencies, graphics houses, my dead grandmother, etc. writing checks for turnkey editing systems, it's just gotten worse.

Bob Kertesz
BlueScreen LLC


BTW there are buttons and settings that allow "Digitize over TC Breaks" in AVID

But that's only one part of the issue here.

Free run Timecode and or Broken Control track also affects:

1) the Downconvert where going from HD to SD with the all important Time code down sequence or the DNA Chain for your EDL.

2) When in HD Online (if you are using that method to assemble your final show instead of AVID DS or AVID Nitrous as an HD finishing tool.)

The Online editor may have to battle the deck and the Tapes with broken control track and timecode if the Offline Editor used any of the footage that was within 5-6 seconds after the break. Reason-as the deck goes into Pre-roll to perform the edit it looses track of the location on the tape if it has to roll over broken Control Track. Now decks can be set to as low as 2-3 seconds but that can create other issues.

So if your going to be inconsiderate to Post at least give them lots of Pre-roll (as in 10 seconds) before calling "SPEED" and beginning the Action.

Lew Brings up a good point if your doing Sit coms with very long takes, Concerts, Award shows, or Sports events where the cameras will be rolling ALL THE TIME. Free run is very handy for that world. but lots of pre-roll is still necessary.

Lets Recap.

But for the most part using Record Run Time code and hitting the "RET" on an ENG Lens, and Assignables set to "Lens return" after power breaks is the way to do things properly.

B. Sean Fairburn SOC
Director of Photography
Castaic Ca


> "a minimum of 8-10 seconds of continuous timecode before the in-point"

Other technologies (e.g. CineRAM) require 0.000 seconds pre-roll.

Noel Sterrett
Baytech Cinema
www.baytechcinema.com


> Actually, my AVID only requires one second of pre-roll. It really depends on the deck being used to digitize - 3 seconds is standard.

Really busy, so a quick one....

1) Avids & most NLE’s WILL dig across t/c breaks if asked to

2) The EDLs/ project's/AAF's created from this will be incorrect, does not matter if it was dig'd in to a Nitris, or an iMovie

3) Short pre-roll will work if the ballistics for the source machine can lock, the F500 manual says 7 seconds, in my experience a DAT can take all of 10 seconds and still not lock

So yes an off-line editor can dig on short rolls, and the producer can pay pay pay for it to be futzed with on an very expensive Hd finishing system

A smart move would be a to ask what the finishing system needs, not the off-line system.

An hour in a nitris would pay for weeks of diging at 10 second handles with necessary pre-roll, day and days of fixing operator stupidity or lack of knowledge is really really not cost effective...... producers were not at all impressed that the assistant got the JH3 to pre-roll at 3 seconds, and went home early, that cost producer's about the same as a trip to Hawaii by the time the project was sorted

If the manual says 7 seconds, and you are not responsible financially for the decisions I would suggest strongly that you follow the manual, or check with the finishing house as they will be the ones on the line, not the assistant that knocked off early....... and when that asst gets back from their trip to Hawaii I am fairly sure that they will hear about it........

My 2 cents as this has been a issue close to me lately

Dermot (final day of mix on a film with it's fair share of stupidity to sort...) Shane
Vfx guy, and now a post sup, used to be a camera guy....
Vancouver, Canada


> a minimum of 8-10 seconds of continuous timecode before the in-point Other technologies (e.g. CineRAM) require 0.000 seconds pre-roll.

Gee that's nice... now how are you going to finish a show with it?

Dermot ( somewhat cranky / no sleep / fixing stupid assistant tricks) Shane
Vfx guy, now post sup, former camera guy....
Vancouver, Canada


> sound guy rolled when the AD called for everyone to settle and already had his 10 second pre-roll

This is exactly what operators should do...as an operator on my first HD24P feature last year, we quickly found out that we should roll as the AD is getting people to settle down. One of the only times when the phrase "tape is cheap" actually helps. On subsequent films with the same camera crew, we were ready for sticks as soon as the AD called for the "roll" queue, having only to wait to hear that sound had speed.

New technologies...new ways of working. Once you get used to it it becomes second nature...

Ken Glassing
LA Based
OP/Dp


Is this why the Panasonic 900 has this pre record to memory feature?

Nick Hoffman NYC DP


Nicholas Hoffman wrote:

> Is this why the Panasonic 900 has this pre record to memory feature?

Maybe. Its also about doing time lapse: save frames to memory, when memory fills up, dump it to tape, and about having rolled some seconds before you hit the record button. There are plenty of uses.

Mark Smith
Oh Seven Films
143 Grand St
Jersey City, NJ 07302


I'm with Bob.

Not only does the person on set take the heat, but the whole production budget suffers when the post-side is all too happy to "fix-it-in-post" and be the hero. Eventually the money comes out of the production side, further inhibiting and stigmatising the production process and the production professionals.

Fix the software!

George C. Palmer
HDPIX, INC.
HD and Digital Imaging
http://www.hdpix.com


George C. Palmer wrote:

> Fix the software!

Hummmmm........ George;

If you hook up a DDR to an NLE they will digitize all day long on a 0 frame pre-roll accurately

Think you might look at the tape based devices with servos, motors, tensioners, pinch rollers to get out of alignment, affected by heat build-up, and miss-use/abuse by bottom feeder night shift tape dogs - and ask your self........

What can a NLE software do about a machine that is inherently unstable?

An NLE is only as good as what is fed to it, hard to ask Avid to fix something when the box will work well if you feed it a stable signal on a 0 frame pre-roll. like a DDR as a source there is no issues

Think you might ask Sony, Panasonic and others to fix their software

Some day we will all be on disks

Dermot (heard the mix with the answer print, now I can sleep.....) Shane
Vfx & Post guy
Vancouver, Canada


> sound guy rolled when the AD called for everyone to settle and already had his 10 second pre-roll

Indeed - I nearly always anticipate roll when shooting HD or Video.

I learned it from a sound guy I often worked with. He's usually barking out 'speed' before the A.D. has even finished calling to "roll sound".

Roderick Stevens
Az. D.P.
www.restevens.com
12on12off


George Hupka writes:

> In situations where you absolutely DON'T have time, it's not the end of the world to have a break in the recording - if it means missing a shot that you'll never be able to re-create, then go ahead and roll.

One way around this sometimes-necessary evil (besides cloning the tape) is simply to give the tape more than one roll number (or A, B, C, etc. extensions) -- one number or extension for each section of unbroken timecode. For some productions the discrepancy between tapes and tape numbers may cause confusion down the line if not meticulously documented, but in many cases it won't hurt at all.

The letter-extension approach should cause the least problems, because it's an existing convention that's often used where an extra number has to be inserted into an existing series.

Martin Heffels writes :

> > Sheesh... If iMovie can take timecode breaks in stride, why can't Avid?

> Don't count on it's bigger brother though; the sound will go horribly out-of-synch if the timecode is dropped.

If you mean Final Cut Pro, it can be set to stop the capture when it encounters a timecode break.

With FCP I almost always clone tapes that have timecode breaks. That seems to solve all problems at once.

Dan Drasin
Producer/DP
Marin County, CA


> If you mean Final Cut Pro, it can be set to stop the capture when it encounters a timecode break.

Yes I know. But it slows down the capturing process to have to restart it every time when the timecode drops. And it's begs the question, why only FCP? The other programs can certainly handle the timecode drop without loosing audio-synch.

> With FCP I almost always clone tapes that have timecode breaks. That seems to solve all problems at once.

Hmmm, sounds I have to consider this too.

Cheers

Martin Heffels
Filmmaker/DP/editor/filmschool techie
Sydney, Australia

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