Variable Framerate

[Gary Adcock]

[AthenRoss] “Can anyone tell me if there is a card (AJA or BlackMagic) that supports the VariCam’s variable framerates (4fps, 48fps, etc.)?”

The AJA’s Kona cards directly support the VFR capture from the varicam. AJA even has a specific setting (720p23.98 VARICAM) that does allow for the user to capture the offspeed content in any codec supported by FCP (including a flawless DVCPROHD capture over HDSDI) This is a real time capture- without the need for trimming the excess from your timeline or waiting for it to process after capture.

This function allows for direct capture from the camera for a truly uncompressed variable frame rate content.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[Videostar]

Hi Gary

You sound like you know the ins and outs of capturing varicam on aja cards so I think you might be able to help me.
I am working with Varicam footage (60fps and 24fps on the same tape) and I’ve been having a lot of problems capturing all my footage form the AJ-HD1200AP via HD SDI on my Kona LHe card with Final Cut 5.

Basically if there is ten minutes (at normal speed) of 60 fps footage at the end of the tape and I try and capture that entire 10 minutes as slo mo varicam footage I end up with only 4 minutes of what was on the tape – although it comes in correctly as a slo mo clip so it is actually 10 minutes long. It seems that I am capturing ten minutes worth of timecode and ten minutes worth of slo-mo video but I should end up with 25 minutes (60 fps over 10 minutes when “converted” to 24fps would be 25 mnutes) of slo mo video! I hope I’m making sense as it’s confusing me. The log and capture window displays exactly whats on the tape while it’s capturing but when I review the captured clip I have exactly ten minutes as slo mo but only 40% of what was displayed on the tape at normal speed between the in and out point.

I’ve called AJA and they didn’t have any solutions for me, I’ve tried different varicam easy setups, I’ve got user-bits turned on in the control panel and it recognizes when the footage being played from tape is 24fps and when it’s 60fps. The footage it captures at 60fps comes in as perfect slo mo but I just can’t capture all of it I can only capture exactly 40% (or 24/60) of what is on the tape between the in and out points. I called panasonic and they don’t think it’s a deck issue – I thought maybe I have to change a deck menu option so it plays out 60fps timecode?

I have been able to capture succesfully going from the deck via firewire and then using panasonics DVCPRO HD converter, but I really want to capture via HD SDI – if only because the card cost 2 grand!!!

Any help would be greatly appreciated.

Thanks

[Gary Adcock]

[videostar] “if there is ten minutes (at normal speed) of 60 fps footage at the end of the tape and I try and capture that entire 10 minutes as slo mo varicam footage I end up with only 4 minutes of what was on the tape”

I think I get this
you have 10 minutes of TAPE at shot at 60fps. Only the first 4 minutes of the tape is being captured via the kona card.

Only use the Kona LH 720p 23.98 VARICAM easy setup.
Use the latest driver and software versions for the OS and FCP?
Was the tape continuously shot? or are there starts and stops? ( FCP should be set to ignore TC breaks)
Do not Use Capture Now. — Set and in and an out point for every clip you try to capture.
Make sure your tape has enough time ( 5-7 seconds) BEFORE and AFTER the In and Out points– FCP needs this for preroll-post roll.

at this point more detail is better
OS / RAM/ Software versions ETC.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[Videostar]

Hi gary

I have tried both Kona DVCPRO HD 23.98 Varicam and the Kona DVCPRO HD 59.94 easy setups. The user-bit option on the kona control panel is switched on and it clearly shows that the card is recognizing when the tape goes from 24fps to 60fps.
I was using Kona Control software version 1.2.1, OSX 10.4.6, FCP 5.0.4.

The tape has continous timecode but they did change framerate on the same tape. It’s all greenscreen and I would typically have a three minute continuous take at 60fps followed by a 24fps slate and 6 minutes of 24fps content before it goes back to 60fps etc.

I didn’t have FCP set to ignore TC breaks, but I did try both capture now and marking in and out over short clips with plenty of pre and post roll. I pretty much got the same result with both. It would capture perfect 23.98 fps slo-mo video but it would only capture part of what actually was coming from the tape. Marking an In at 30:00:00 and Out at 40:00:00 would capture ten minutes of slo-mo video at 23.98 but the tape was playing ten minutes at 60fps which should be stretched out to 25 minutes at 23.98fps right? That’s how it works out when you go the frame rate converter route anyway, which is what I had to do in the end because the deck had to be returned to the rental shop this morning.

My work around was to capture all the 24fps as normal using the Kona DVCPRO HD 23.98 Varicam easy setup over SDI and then switching to the DVCPRO HD 720p60 easy setup and capturing the 60fps footage over firewire and using the frame converter plug-in to expand my 59.94 clips out to slo-mo 23.98 clips. Surely this isn’t how everybody works!?

As somebody who obviously has worked with varicam a lot can you tell me what I should expect to see when successfully capturing 60fps Varicam footage? In my example above I had 10 minutes (from 30:00:00 to 40:00:00) of 60 fps footage on tape. If I marked my ins and outs and captured correctly I should end up with a 25 minute long 23.98fps slo-mo clip right? So what timecode would the 25 minute clip have? Does the card just generate new timecode (which has no reference to the source on the tape) so that my twenty five minute 23.98 slo-mo clip starts at 30:00:00 and ends at 55:00:00? If it does then how would you recapture such a clip from tape if the clip doesn’t reference actual tape timecode?

I will be doing plenty more Varicam jobs so I need to figure out what I’m doing wrong here. I would imagine that a LOT of people are capturing off-speed frame rates via SDI successfully – otherwise nobody would use varicam or AJA cards right? – so I must be doing something wrong.

I appreciate any help you can give me, thanks!

[Gary Adcock]

[videostar] “The tape has continous timecode but they did change framerate on the same tape”
But that Speed change will cause a cadence error, and if that break in the cadence is within the preroll/post roll it can cause an issue with the capture.

[videostar] “It’s all greenscreen and I would typically have a three minute continuous take at 60fps followed by a 24fps slate and 6 minutes of 24fps content before it goes back to 60fps etc.”

IF the Camera OP is doing this – they have never been educated in the right way to work with the camera. Offspeed content should be visually slated at speed so that the editor has some idea AND has the ability work around TC breaks. I as a Producer demand at 10 seconds or more of CAMERA roll prior to the start of the VFR content I need to capture. IF it cannot be visually slated I tell them to block the lens with something so i have enough material on tape to work with.

[videostar] “Marking an In at 30:00:00 and Out at 40:00:00 “
where are you getting 40 minutes on a Tape??? The longest in-camera record is 33 mi

[videostar] “can you tell me what I should expect to see when successfully capturing 60fps Varicam footage?” it should and does work just like the FRC does in software

preroll / post roll needs contiguous Frame Rate AND Time Code to work properly. If there is a speed ramp or a break in the TC it is going to reject the capture. This is what it sounds like is happening to you.

[videostar] “So what timecode would the 25 minute clip have?
the Offspeed content always has the TC stripped away -the audio too!.

[videostar] “If it does then how would you recapture such a clip from tape if the clip doesn’t reference actual tape timecode?”
The original FCP file maintains the base TC info but do to the frame rate change FCP will ignore that reference
so you will get some of the info but not all of it.

if you are going to recapture you need to master the FRC converted files to a new tape.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[Videostar]

Thanks Gary!

I’ll be capturing some more varicam in a couple of weeks so I’ll make sure the DP on the shoot follows your advice.

Also they have used two different tapestocks over two different varicam shoots so far. One is large format Panasonic DVCPRO HD 92/46 L with the red tape guard on top of the cassette and the other tape stock is
Panasonic DVCPRO 50 92/46 L with the blue tape guard on top of the cassette. I didn’t know you could use the DVCPRO 50 stock for a HD shoot but there you go.

Thanks again for all your help.

[Gary Adcock]

[videostar] “Panasonic DVCPRO HD 92/46 L with the red tape guard on top of the cassette and the other tape stock is Panasonic DVCPRO 50 92/46 L with the blue tape guard on top of the cassette”

All of the Panasonic Tape stock is the same- as Far as I know only the Fujinon branded tape for HD is usually first run/ best quality–

All of the Panasonic tape stock is all first quality – the color coded labels were added so that people shooting different formats would not get the tapes confused when grabbing them from their bag. (according to Jeff Merritt)

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[Athenross]

Hi Gary!

Thank you so much for the response! I apologize for my absence from this post (been on vacation). So if I understand this correctly, the AJA Kona Cards will support the offspeed content directly (as in time lapse and slow motion content). Will the Kona LHe do the trick, or is there a different one? I would need at least the LHe in order to up-rez 720p content to 1080i. If the LHe will do the trick, I will be at MacHollywood as soon as I return!

Thanks again, Gary!
~Athen

[Gary Adcock]

[Athenross] ” the AJA Kona Cards will support the offspeed content directly (as in time lapse and slow motion content). Will the Kona LHe do the trick, or is there a different one?”

All of the Kona HD cards do this (the LS is an SD only card)

[Athenross] “I would need at least the LHe in order to up-rez 720p content to 1080i. If the LHe will do the trick”

Only the Kona 3 supports cross conversion from 720 > 1080

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows
Chicago, IL

[Athenross]

All of them do? Terrific! So the BlackMagic ones do not? Someone told me they don’t, which concerned me about the Kona cards as well.

Yep, I realized my mistake in the LHe when it is the Kona3 that I need. Gonna pick it up on Monday!

Thanks a bunch Gary!
~Athen