Canopus ADVC-110 for digitizing Hi8?

[Gary34]

Quote:

Your TBC is before the capture card because it cannot be connected after the capture card, It doesn't mean it is processing in analog, it is digitizing the signal first, then processing it and then converting it back to analog.

I still think the proc amp adjustments on my TBC are being made when the signal is analogue. The monitor composite output is analogue and it doesn’t have the proc amp adjustments on it even though the output from the device does so the composite monitor output is before the proc amp. You can view simultaneously before and after proc amp adjustments that way if you were wanting to view a reference through a CRT. Since the signal goes digital in the TBC why would they put an analogue output there then turn it back to digital to process it in a proc amp?

-- merged --

Here is what I am talking about with that. You can see it has a tint adjustment I made on the proc amp in my TBC but the CRT I have connected through the monitor preview doesn’t pick up any proc amp adjustments which leads me to believe that the proc amp is not making the adjustments when the video is digital.

[latreche34]

The monitor output A is to monitor source A input, The same for B, The TBC digitizes the signal and applies proc amp, timing ...etc and convert to analog and output via the output (non monitor output) for recording or editing which is its purpose back in the day, the receiving device should be connected to another monitor so you will see before and after adjustments, But if whatever you believe makes you happy, so be it.

[Gary34]

I’m not trying to argue. I’m just trying to figure it out. I just don’t thing that the proc amp in my TBC and my card are doing the same thing and it seems like what the capture card can do could just as easily be done in software later. That’s all I’m saying.

-- merged --

You are probably right. You are really experienced. Okay you’re right they correct the same way as a capture card they are just before the card instead of in the card.

[lordsmurf]

I've stated for years that capture card "proc amps" are not true proc amps (processor/amplifier), and operate in the post-capture digital domain. It's a bad borrowed term.

I remember running extensive tests on true proc amps (SignVideo, others), weenie proc amps (inside TBCs such as AVT-8710), and in VirtualDub/etc software connected to capture card drivers (AIW, various USB cards, etc). This was long ago, 10+ years now, so I also tested some broadcast gear I had access to at the time. There was a stark difference on how effective adjustments were.

From a very obvious mechanical POV, the board parts required (and space on a board) do not exist for analog adjustment on input on capture cards. Not even on larger ATI AIW boards, certainly not on cramped USB boards. Nor DVD recorders, nor Canopus DV boxes, etc.

What you get on capture cards is digital domain post-ingest controls, with limitations and baked-in flaws. Some cards suck more than others, namely Canopus DV boxes when it comes to the integrity of color (and that's just raw, without "correcting" it in any way).

The one exception may be luma gain, because it would be needed for AGC (which exists on all cards). That value seems to be analog adjusted on input. Sometimes user adjustable, sometimes not. VirtualDub/software "proc amp" varies highly here on the brightness control, for that reason.

For true proc amp, each input needs a dedicated controller/chip/pathway/whatever (words/jargon escape me at the moment). You can't just cram a raw signal in, and expect it to "figure it out" (automagically). It can't all be mushed together in that way.

The main reason a TBC-3000 board is so large is to accommodate proc amp.

Though very false, the common myth is that software can fix anything. Manufacturers probably knew it was bunk, but went with it anyway. If everybody wants to correct color in software, why bother increasing costs and complexity of a capture card? So just skip it, AGC the luma, and done.

Quote:

Originally Posted by aramkolt

What is well established is that DV capture devices never have audio sync issues

This is false. There is nothing special about DV capture cards. Those can, and do, lose audio sync just as easily as anything else. I've seen this many, many times over the years (decades, actually, as Canopus are ancient technology from the 1990s).

Quote:

Originally Posted by Gary34

I have a TBC 3000 that I got from the original owner and he used if for a month. It was kept in his office since. It’s possibly a 5th gen. Even LS hasn’t tested the 5th gens.

It eludes me. Production had to be extremely low. I believe that I've now used every DataVideo TBC model (and sub-model), except for that one.

The unfortunate aspect for you is that the 3rd/4th gen "interlace error" may be approaching. All of my 3000 units are failed. Something, somewhere, still not located, is causing it. KhAoS182 claimed to have found it, but I've not had time to ask him for more details.

[latreche34]

It always comes down to the quality of the design, Serious gear such as pro, semi pro and institutional tend to have larger size because of the bigger number of components used and the quality of the circuit design, consumer stuff is cutting corners and adopting software control over physical knobs, no monitor output and just good enough for the main job which is capturing. I was explaining the principal of DSP which all digital equipment use, pro or consumer alike, Results however, differ obviously based on the quality of the gear.

[Gary34]

Quote:

The unfortunate aspect for you is that the 3rd/4th gen "interlace error" may be approaching. All of my 3000 units are failed. Something, somewhere, still not located, is causing it.

I’ll keep my fingers crossed. I hope you guys figure it out.

I have at least always used a UPS. I keep a de humidifier in there too. The UPS for sure and maybe the dehumidifier are things I wouldn’t have done without the advice on this forum. I’ve seen a bunch on eBay and they will have some random power supply they got from Amazon on them. I definitely appreciate the forum and what it does to try to prolong the life of gear. I’m thinking the number of bad units on eBay is A LOT higher than I thought when I first got into this.

Quote:

I remember running extensive tests on true proc amps (SignVideo, others), weenie proc amps (inside TBCs such as AVT-8710)

Since Latrech brought up DSP I am wondering about it now. So the SignVideo proc amp actually operates in analog but an AVT 8710, TBC 3000, etc. makes its corrections digitally while the frames are being stored in a buffer? So the analog monitor output from a TBC 3000 is from before the signal gets stored in a buffer?

[lordsmurf]

Quote:

Originally Posted by latreche34

It always comes down to the quality of the design,

Yep.

Quote:

Originally Posted by Gary34

I keep a de humidifier in there too.

DE-humifier? Watch that. You don't want static to build up. How are you gauging that room for proper humidity levels at the computer? Don't trust the on-unit meters, trust something near the item need to have less humidity. (Even I don't do this much. Needs vary by area, and even home design.)

Quote:

I’ve seen a bunch on eBay and they will have some random power supply they got from Amazon on them.

Fun fact: those cheap units can nuke the device. So $5 PSU from Chine + $K TBC = failed TBC! Only buy OEM and name-branded PSUs. Most people are not aware of what "name branded" means, so learn it. For example: Honor, APD, Jet/ENG, Group West.

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I’m thinking the number of bad units on eBay is A LOT higher than I thought when I first got into this.

Shockingly so. I wish eBay would report when items were returned/refunded. It's much higher than people seem to realize. In actuality, functional electronics gear is huge risk to both buy or sell there. Far too many sellers are just recyclers and resellers, and have zero clue about how the gear should function. I recently saw some VCRs and TBCs listed, and I can 100% guarantee the buyers were in for a disappointment. All they saw was a cheap bid/buy price, but I saw red flags that reveal it to not work. I can only wonder if the buyer will find his/her way here, or if it will take them more than 30 days to realize it's a lemon.

Quote:

Since Latrech brought up DSP I am wondering about it now. So the SignVideo proc amp actually operates in analog but an AVT 8710, TBC 3000, etc. makes its corrections digitally while the frames are being stored in a buffer? So the analog monitor output from a TBC 3000 is from before the signal gets stored in a buffer?

Get schematics, or trace the boards (as best as is possible).

[aramkolt]

So what would be the ideal test for proc amp performance?

I think if the signal remains truly analog, levels should never clip on bright areas for one. Black areas should be clippable on both analog and digital proc amps since the lowest the signal can go is zero volts/zero IRE and you can't bring it back if you try to amplify a zero value later. It would make more sense for a TBC to do proc amp changes digitally, but since the values are all truncated to whatever color bit depth that the unit processes at, the question again becomes about whether they will clip incoming or outgoing values.

The main advantage to analog processing is that there is no "bit depth" (8 vs 10 vs 12 bit), so you won't get any "banding" on scenes where the scene is mostly the same color like sky/sunsets or just very dark scenes where most of the scene is roughly black. The issue being when everything I almost the same color, all of the newly create pixels will get "rounded" to the same nearest value and that's where the banding or possible blockiness comes in. The recommended TBCs are all 8 bit which for the standard capture process doesn't matter since the captures are also 8 bit, but if you were capturing in 10 bit or higher, a TBC that does 8 bit or less conversions is going to negate any advantage of doing a 10 bit capture, so that's something to consider. This is one reason why I like ProRes422 - it is 10 bit and the format can preserve illegal values at least up until a point which could be brought back down in post processing if desired without losing that "normally clipped" information.

The DPS-475 (rackmount TBC) is notorious for "Pre-clipping" any IRE values higher than 115 - so you could feed it hot luma and even if you adjust levels down later, it'll show as very flat/clipped on anything that was higher than that on the input. I'm not totally clear on whether this is just with composite or if also with S-Video though since I haven't tested it personally yet.

Other TBCs are perfectly happy accepting boradcast-illegal levels and outputting them as illegal levels as well without clipping - at least to a point. The TBC-1000 I am pretty sure will accept and output illegal levels, but that doesn't have a proc amp to really do proc amp testing.

The basic test I was going to do in my broader testing is feed a known hot signal from a pattern generator or still frame which is boosted by a known analog proc amp to say 130IRE and see what the capture card or TBC can bring the levels back down without clipping. If they can, then it's more or less acting like an analog proc amp in that way. This same test also would be a way to check if automatic gain control is particularly effective to get levels to legal values before they leave the VCR or get assigned digital values on say a capture card.

[latreche34]

This is the area where pro gear shine, 12 to 14bit processing vs consumer 8 to10bit processing, This is also what distinguishes proc-amp processing during capture vs post, Because once the file is created it will be 10bit at most (8bit consumer) so the opportunity to process at higher sample rate is missed.

[Gary34]

Quote:

DE-humifier? Watch that. You don't want static to build up. How are you gauging that room for proper humidity levels at the computer? Don't trust the on-unit meters, trust something near the item need to have less humidity. (Even I don't do this much. Needs vary by area, and even home design.)

Yes a de-humidifier not a humidifier. It’s in a 10 by 10 non corner 1st floor room with basically no sunlight due to a hill blocking it. The whole room stays pretty well the same. I keep the humidity at 45. I have a AcuRite Indoor Digital Thermometer & Hygrometer. I’ll throw a thin sheet over my gear and unplug everything if I’m not using it for two weeks or if there’s a storm coming.

Quote:

Fun fact: those cheap units can nuke the device. So $5 PSU from Chine + $K TBC = failed TBC! Only buy OEM and name-branded PSUs. Most people are not aware of what "name branded" means, so learn it. For example: Honor, APD, Jet/ENG, Group West.

I saw a TBC 3000 on eBay that said power cord not included but it is tested and working. Out of curiosity I asked him how did you test it if you don’t have the power cord and this is a copy and paste of his reply “Hello, It was tested with a cord that I have. It is not the original cord and I keep it for testing other units. They sell cords that fit it for about $15 on Amazon.” He sold it to somebody.

Quote:

It would make more sense for a TBC to do proc amp changes digitally, but since the values are all truncated to whatever color bit depth that the unit processes at, the question again becomes about whether they will clip incoming or outgoing values.

I’m trying to watch what I say this thread since I was blatantly wrong for half of it but I’ll just say I don’t see any clipping. My card clips until I push values into legal range and I’m not having to use close to the full capabilities of my TBCs proc amp. My tapes were shot on cheap gear inside and the values are pretty off.