Offline/Online Frame Accuracy Issue

[Shane Ross]

Thoughts….

Is this 720p DVCPRO HD or 1080i DVCPRO HD? 720P runs at 60fps, so the 30fps DV offline might be throwing off the code? Confusing it somehow?

Are you capturing via Firewire or via a Capture card? Firewire deck control isn’t always frame accurate, and I have had frame accuracy issues when capturing DVCPRO HD via firewire. Which is why I now capture it via SDI and RS-422 Deck Control.

Why offline? DVCPRO HD 720p is roughly double the space of DV…maybe 3x the space….not much. And drives are cheap, so why not skip the offline step and capture at full online quality? For the future, of course.

Shane

GETTING ORGANIZED WITH FINAL CUT PRO DVD…don’t miss it.
Read my blog, Little Frog in High Def

[Matt Doe]

We have run into the issue with both 1080i/59.94, 720p 60 and 720p 23.98 (with the Kona removing the flagged frames).

We are using Kona 3’s w/ 422 control for our uprez capture, though the offline material was captured on both LHi’s and LHe cards.

We plan on editing natively for our shows that have less footage, one offs and such. But the majority of our work has such a high volume of offline footage, in the thousands of hours (American Loggers and soon to be Real Housewives of Washington DC) that we would eat up all our 90TB XSAN pretty quick if we were to cut those series natively, thus the offline/online workflow.

We just installed all new ingest machines and are running tests and ensuring every machine is set up the same, so in the future hopefully that solves the issue.

[Aaron Neitz]

What’s the frame rate of your offline footage? the 1080i stuff should be simple – but I can see 720/60 and 720/24 causing headaches if you’re offline is DV-29.97

i have zero experience with the 1400a and DVCPRO-HD tapes workflows. But I do know my Kona 3 system has a much better time with frame accuracy when I REMOVE the Gen10 from the workflow and set everything to input video.

[Matt Doe]

We cut our 23.98 offlines in 23.98 DV, set-up the Kona as if we were going to capture the HD, except we change the compressor in the Audio/Video settings to DV compression, end up with 720/480 23.98 Anamorphic DV for offline.

Could that be the issue? We have the Kona doing all the down-converts off the HD-SDI. In the 29.97 realm would taking the down-convert out of the deck be more reliable?

[Shane Ross]

So your main footage is 23.98? 720p24 with flags? Or 1080i24PA with flags? It might be an issue with how you captured the offline DV. Might see if capturing then reverse telecine would work better.

Shane

GETTING ORGANIZED WITH FINAL CUT PRO DVD…don’t miss it.
Read my blog, Little Frog in High Def

[Matt Doe]

Would the flags be carried on the downcovert through the Kona? As in, take HD-SDI out of the deck, the Kona downconverts to DV without pulling out the flagged frames, then reverse telecine the DV files to end up with 23.98 offline media? I am not very familiar with reverse telecine.

The show I am currently slipping in to place is 720/24 DVCProHD with flags (removed by the Kona card for both the offline and online captures).

The rest of our shows are 29.97, either 720p/60 DVCProHD, or 1080i from HDV cameras that we end up capturing at DVCProHD (we are moving to ProRes for all our onlines from here on out after this current show is donezo next week) for the online, and the DV offline material is downconverted through the Kona for the offlines.

[David Chai]

We had inaccuracy issues with Deck control capture and layoff until we moved to Blackmagic Decklink. 2:3 pulldown removal perfect everytime. Laying off – frame accurate every time. On Kona 3, 1080p to 720p 23.98 worked with D5, but never worked with HDCAM SR. Decklink, works every time.

Aja make great hardware, but their drivers for RS422 in FCP are sorely lacking. Try changing the frame offset in the Control settings. They do not change anything.

I do not work for Blackmagic, this is just my personal experiences.

—————–
David Chai
Director . Camera . Editor
http://www.davidchai.com
dc@davidchai.com
212 363 0159

[John Pale]

You might want to upgrade to FCP 7. The new ProRes Proxy resolution (very small file size, but still HD) might be easier than the DV workflow you presently use.

[Ken Jones]

I have never had a problem capturing DVCProHD via HD-SDI with a 1400a. The deck seems to work perfectly and doesn’t appear to get “lost” searching for time-code. But, I have always captured entire tapes and have never attempted to “frame accurate re-capture” when working with DVCProHD.

However, I have had nothing but trouble attempting to capture HDV via HD-SDI with my Sony HVR-1500. Please see my post here: https://forums.creativecow.net/thread/8/1007581#1007581

And here: https://forums.creativecow.net/thread/126/859595#859595

The only workaround I have found is to change the deck pre-roll to ten (10!) seconds.

I attended an Apple/JVC sponsored event last week and I asked the Apple FCP rep about this problem. He confided to me that “Apple really doesn’t care about I/O issues with tape formats”. He said that they really don’t want to change anything if the majority of users aren’t having any issues for fear of breaking something else with deck control.

A few months ago another Apple FCP tech assured me that this issue would be taken care of “when the new software comes out”. Guess what? I upgraded to FCP 7 and still have the EXACT same issue…

[Doug Beal]

Hello Matt
we have issues with HDV that TC is not repeatable.
We bump any HDV up to HDCam generate new code and move on. in your case thats a lot of expense.

Depends I guess on how much more time against what deadline in edit VS tape cost for reliable TC

Any offline/online workflows we work with esp SD from HD we cut with BITC in the letterbox generated by the machine playing the tape. No doubt as to what frame it is.
If BITC is in the letterbox a simple crop removes it for viewing purposes, If coming from HDCam 23.98 to 29.97 both TC windows are available ORG and PDT (pulldown TC)

Doug Beal
Editor / Engineer
Rock Creative Images
Nashville TN