TBC on Digital 8 / Video 8 camcorder - to use or not to use?

[echo1434]

Hello all,

Out of curiosity, I made some screenshots to compare the effect of the TBC on my Sony DCR-TRV480E Digital 8 camcorder. For those who don't know, this unit can play analog 8 mm/Hi8 tapes and output them to DV format via FireWire.

At first glance, I didn't think the TBC has any effect on the image, but the screenshots show an interesting difference. If you do a side-by-side comparison, or look at them back-to-back in an image viewier, the TBC'd image is a bit less saturated. I'm not an expert in this field, so I'm wondering if this is a "correction" of sorts, if it's just a flaw that the programmers overlooked, or possibly something else.

Clearly, the TBC shifts the image to the left and slightly up. This is not really an issue here, as it just hides that ugly line on the left of the screen.

But I would really appreciate if someone with more experience could give me an opinion on which image is "better". Perhaps stagnant images aren't the best comparison, but maybe something can be gathered from them.

These images are unprocessed, direct transfers from my camcorder. The only difference is the TBC being turned on and off.

First, the TBC'd image:




And now with no TBC. As I said, the colors are a bit more vibrant here. Pay special attention to the blue-ish patterns on the upper half of the screen.




So, I'm kind of stuck for now. The raw footage seems a bit "prettier", but it may lack whatever corrective measures the TBC is providing.

Or is this extra saturation on the non-TBC image something that shouldn't be there? After all, the people in the crowd seem to look a bit too yellow

I know it's kind of hard to tell by just one still, but any opinions are welcome. I can post short video clips or more screenshots if anyone is up to the task. Thanks in advance.

[sphinx99]

I experienced the same effect with my TRV820. After much much analysis (some of which might actually be posted on these forums from way back) I elected to turn it off for all my captures. The TBC seemed to muck up the color, shifts the image and did a few other things. I was using an EV-S7000 and its on-board TBC as a reference--the deck TBC did what a TBC should do (clean up certain kinds of artifacting due to clock/sync issues) without touching the color.

I also found that the TRV820 seemed to do an incredible job of digitizing video with the TBC off--it actually extracts more usable video than the $2000 deck did with its TBC on.

[Capmaster]

The raw footage seems a bit "prettier", but it may lack whatever corrective measures the TBC is providing.

Keep in mind that built-in TBCs in camcorders are almost always "line" TBCs and are slightly more than afterthoughts. They correct the horizontal line timing, but do nothing for the vertical timing. They help, but not as much as you might think. You won't get the same benefit you would with a serious TBC. The full TBCs are "frame" TBCs.

The full TBCs cost quite a bit more because they have full frame buffers, and that means expensive buffer memory.

[plehoediv]

I know this is old, really old, but you never know...

I am thinking of getting the TRV820 but I saw that you can only use RCA to the Camcorder. At least that is what the manual shows. I googled and saw s-video to 3.5mm cables. Would those work? Reason I am asking is: s-video is "better" than RCA, correct?

Thanks.

[oln]

That model seems to have both S-Video and rca out, you can see it in the service manual and in pictures of it online. Afaik when it comes to digital8 camcorders only the very last generation (like the DCR-TRV480, DCR-TRV238) lacked the S-Video out. The analog/hi8 models from that last generation plus some earlier lower end analog Hi8 models also lacked it (the same ones typically lacked stereo fm audio as well).

[plehoediv]

Hi,

Thanks for the fast reply. However, I think we misunderstood each other, or, most likely, I didn't make myself clear enough. I am talking about using the s-video out of the VCR to go in the AV In (3.5mm) on the camcorder.

Thanks.

[Alwyn]

I am talking about using the s-video out of the VCR to go in the AV In (3.5mm) on the camcorder.

It doesn't explicitly say it in the manual, but it does say you can output video from the camera's S-video port. I therefore assume you can input it too, from the VCR. Given that one of the advertised features is AV>DV passthrough, I'd be very surprised if it didn't have S-Video In. That would give you a better video signal than Composite (yellow plugs). You would still need to use the 3.5mm plug to transfer the audio.

I googled and saw s-video to 3.5mm cables.

But did it include the audio plugs? I doubt very much you could get s-video+audio on one end and 3.5mm Composite+audio on the other.

Added:
Found this on this forum:
"As for your other question, all these camcorders (well, the north-american ones anyways) can record from a line-input (S-video) and from 2 other jacks - Sony calls one a "Special video in/out" and the other is "iLINK DV In/Out".

[plehoediv]

I am talking about using the s-video out of the VCR to go in the AV In (3.5mm) on the camcorder.

It doesn't explicitly say it in the manual, but it does say you can output video from the camera's S-video port. I therefore assume you can input it too, from the VCR. Given that one of the advertised features is AV>DV passthrough, I'd be very surprised if it didn't have S-Video In. That would give you a better video signal than Composite (yellow plugs). You would still need to use the 3.5mm plug to transfer the audio.

See, I wasn't even thinking about going into the s-video port of the camera. I was just thinking about using the s-video out port of a VCR using a s-video to 3.5mm cable. But let me ask you this: Using a s-video to 3.5mm cable, should yield better quality, than using RCA to 3.5mm, or not really? I guess s-video to s-video would be ideal, but if that wouldn't work, s-video to 3.5 should be the next best thing. Right?

I googled and saw s-video to 3.5mm cables.

But did it include the audio plugs? I doubt very much you could get s-video+audio on one end and 3.5mm Composite+audio on the other.

I am not sure, didn't pay attention to that. However, I do not mind using an extra cable for audio, as I am doing this now anyway. (VCR to capture device)

Added:
Found this on this forum:
"As for your other question, all these camcorders (well, the north-american ones anyways) can record from a line-input (S-video) and from 2 other jacks - Sony calls one a "Special video in/out" and the other is "iLINK DV In/Out".

Thanks, but I am missing the significance of this post? I am not looking to record with the camcorder, just want to use it as a passthrough device. Ahhh! wait a minute! Now after writing this, I realized that "recording" means IN. That is great.

So VCR s-video out to camcorder s-video in, from there camcorder out via firewire and then into the PC!

Thanks.