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Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Sat Sep 02, 2017 1:21 am
by Dmytro Shijan
Currently i try to re-capture few 10 year old Hi8 tapes. In early days it was done with simple TV tuner with Composite input. Quality was ok but not perfect. Currently i got Intensity Pro capture card and Hi8 camera and decide to re-capture those tapes in better quality with S-Video input. 10 bit codec and S-Video makes real improvement and overall i am happy with result, but i find unexpected problem.
Few videos must be captured with real time artistic effect "Fast Forward/Backward" but when i press Fast Forward on the camera capture card just shows me black screen until i start to play video normally. Problem is definitely lays in Intensity Pro card driver because see "Fast Forward" effect in camera viewfinder and in monitor attached directly to camera output. Also i try two different capture apps.

Beside Fast Forward/Backward artistic effect this problem sometimes became visible in regular videos with too many analog interference. Instead analog tape interference it shows random dark frames which looks like dropped frames.

Dear Blackmagic team can you please update firmware and add option do not mute Fast Forward/Backward preview?

:arrow: Here is a video illustrating this problem: https://www.dropbox.com/s/j68cxpqpjpp2f ... 2.MOV?dl=0

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Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Mon Sep 04, 2017 8:30 am
by Peter Cave
Analog tape sources need stable sync to capture. Fast forwarding the tape renders the analog sync unusable and the capture will not work correctly. You will need something like a time base corrector or feed the signal through another video deck that can stabilise the signal.

Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Mon Sep 04, 2017 8:00 pm
by Dmytro Shijan
Ok great! Time Base Corrector is the only way to go.
One more delay in work due BM forget to solder Time Base Corrector circuit into their capture card and Sony forget put it into their $2000 hi-end customer CCD-TR3000 camera in 1995 as well.

Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Sun Sep 10, 2017 5:38 am
by Peter Cave
It's not a BMD issue. It's always been an issue with all equipment from way back in the analog days, even with expensive high-end studio & post production gear.

Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Sun Sep 10, 2017 6:37 am
by Dmytro Shijan
For unknown reason some cards just have build in TBC but some not. For example in far past i use very simple consumer Pinnacle capture card with tv tuner. Every Fast Forward action from camera was perfectly visible there, no any black frames at all. But that card have a lot of different problems and it is Windows only.
BTW I find a lot useful info about TBC and analogue capture devices and cards at The Digital FAQ forums http://www.digitalfaq.com/forum/ Ended up with used Kramer FC-400 Time Base Corrector/ Frame Synchronizer to be safe in future with any camera and any capture card...

Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Sun Sep 10, 2017 11:20 am
by Andrew Kolakowski
It's because these days no one cares about analog, so products are simple and not very reliable. Analog signals are quite "difficult" compared to digital.

Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Thu Sep 14, 2017 3:12 pm
by Colin Barrett
I remember using a Pinnacle DC30 card back in the early 90s (when I used to test and review video gear for specialist magazines) and although it coped pretty well with a lot of consumer analogue video playback gear, it would still fall over and stop capturing when there was a serious sync hole in a tape sequence.

As has been correctly mentioned above, there's only one cure for analogue video capture to digital and that's a good broadcast-spec TBC. That's why they were designed in the first place (by the BBC in London)!

The big problem that Blackmagic users like me have is that analogue-to-digital video capture for archiving purposes just isn't a big enough priority for BM's product developers anymore. Unfortunately. :cry:

Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Fri Sep 15, 2017 2:51 am
by Peter Cave
Hi Colin,

just in case you are interested, timebase correctors were invented by Ampex to enable playback of their 2" quad recordings back when video recording was being developed. Without a timebase corrector the video was not viewable at all!

Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Wed Sep 20, 2017 9:13 pm
by Dmytro Shijan
Kramer fc-400 arrived today and i do some tests with it. It works well, now i can playback damaged tapes that where 100% unusable before even with VCR build-in TBC. No more black dropped frames at all. But "Fast Backrward" effect still unusable, it looks like ugly 5fps stop motion animation. "Fast Forward" effect looks natural but slightly shifted up. When i press "Pause" sometimes i can see paused image but sometimes not.

I remembered now that my tape with "Fast Forward/Backrward" effect was captured long long time ago on some TV studio on high qualty gear, but they compressed it to XviD because It won't fit to DVD-R :) Later i re captured all my tapes on Pinnacle card at home but was unable to recapture this tape because that "Fast Forward/Backrward" effect. So i keep that XviD copy from 2004 till now. Really wonder what gear was used that time. It is possible that they use professional Hi8 VCRs on that studio and i try to capture this tape from consumer Hi8 camera.

Kramer fc-400 is pretty simple gear but i can not understand the purpose of those four small rotary switchers in front. Manual says that they adjust SCH and SYNC PHASE but when i turn them i can not see any effect on the output image. Maybe they should be used only in pair with external Genlock sync? If anyone knows something about it please let me know.

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Re: Intensity Pro don't capture "Fast Forward" tape effect

PostPosted: Thu Sep 21, 2017 12:26 am
by Howard Roll
Those are for subcarrier phase (color/hue) and h-phase (timing). If you wanted to put something through an analog switcher like a consumer vcr you'd need a tbc to gen lock the signal and then you'd have to set the sc phase and time the signal. Without external reference those pots don't probably don't do anything.