Possible to 'Genlock' via S-Video output?

[cameronhamill]

Hi Members,

VHS > PC Genlocked / Blackburst Video precise in sync captures

Is it possible to Genlock in this fashion? Is this a good setup? Also how do I route my audio with this set-up?

Is this set-up any good? What would I achieve if I did this?

1) JVC S-VHS VCR HR-S7600AM (using the S-Video output)

http://www.audioreview.com/cat/home-video/vcrs/jvc/hr-s7600u/prd_117455_1588crx.aspx

> then into the BNC* input on a 'For.a' (brand name) Frame Synchronizer & TBC FA-128
* Utilizing an S-Video to BNC converter cable

http://www.for-a.com/products/fa128/fa128.html#Tab2

2) FA-128 (using the BNC output)

> then into a BNC input of a Black Magic Design Sync Generator (Black Burst Generator)

http://www.bhphotovideo.com/c/product/558912-REG/Blackmagic_Design_CONVMSYNC_Sync_Generator.html

3) Black Magic Design Sync Generator (using the BNC output)

Finally

Now do I have a perfectly genlocked / black burst signal to feed the Decklink card? Is everything perfectly timed at this point?

I assume now I won't lose any sync when I feed the PCIe capture card. Is this a fair assumption?

into the BNC of;

4) Black Magic Design Decklink Studio PCIe Video Capture Card

http://www.bhphotovideo.com/c/product/558912-REG/Blackmagic_Design_CONVMSYNC_Sync_Generator.html

[Cornucopia]

You have a misunderstanding of what genlock is meant for. Genlock is used to distribute clean sync pulses to multiple devices, so that those multiple devices can all match their sync timing, allowing easier live video mixing and editing/compositing. VERY useful in stereo3d work, for example.
But most modern workflow chains that have a single out-in pathway don't need this because most modern equipment can sync to source timing when provided with only one input. Times when this doesn't work are usually due to the input signal having UNSTABLE sync. When that happens, a TBC, or Time-Base Corrector is necessary.

Scott

[sanlyn]

Your JVC player has a line-level tbc, your FA-128 has a frame-level TBC, so go straight to the capture card. And since you already have this complicated setup, why don't you just capture something and check it out?

[cameronhamill]

Thank you for your detailed replies gentlemen. I really appreciate your expertise in this area. I was considering the for.a FA 128 but I already have a DataVideo TBC-1000.

May I ask these further questions?

Is the TBC-1000 a 'line' or a 'frame' level TBC? Which is superior?

Is there any benefit to leaving the TBC on the JVC set to ON and feeding it through the TBC-1000?

Leave JVC TBC ON or OFF if feeding through the TBC 1000?
Is it better to utilise both the JVC and the TBC 1000's TBC? I have a very 'chewy' old tape.

[Cornucopia]

TBC-1000 = Full frame TBC.

Generally, line-based and frame-based TBCs do DIFFERENT things to the signal, so one can't really say one is superior over the other. They can often complement each other (there are a FEW exceptions).

When running through a capture chain process, one should try out all 4 variations to see which signal gives the best quality:

1. Line-based TBC only
2. Frame-based TBC only
3. BOTH
4. Neither

Sometimes, it's even good to capture variations in different passes and combine/blend in an editor/compositor/processor, to get the best of both worlds.

It can be a trial to do multiple passes if the tape is already physically compromised. If it were me, I would try manually repacking the tape on the reel (with some corrective cleaning & flattening if necessary) to help the tape run through the player better (important to have smooth, even "interchange"). Then, I might run a short-way pass of a few small sections to test the signal. Then repack again and do final full pass(es). Warning: to do this optimally, this can get quite time-consuming.

Scott