Filters to use, levels when recording?

[Chanuka22]

Hi guys

My PAL workflow:
JVC HR-S7611 --> ES15 --> AIW 9600 XT --> TurtleBeach Audio Card (internal AUX connection) --> VirtualDub

The computer I'm using:
XP SP2 32bit on an AsRock 775i65G R2.0 board

Most of my tapes are family VHS-C tapes (those small ones) which come from one or more camcorders primarily from the 90s. They haven't been played must and are actually great quality. I use a VHS-C adapter for them.
The other tapes I have are commercial tapes, e.g. a lot of Disney tapes.

Actually my recordings are going quite well. I know the ES15 i TBC'ish at best, and that I should not really have 2x line-TBC in the chain, so if I insist on the ES15 I should turn off TBC on the JVC VHS or remove the ES15. However, I ran some tests, and as soon as I remove the ES15 I have dropped frames which is a hell. I also concluded that I'd rather have the line-TBC on on the VHS than off - again by comparing test recordings.

Anyway, that's not questions, but just a bit about my setup, which maybe can help others in the future .

My questions are in regards to using filters and fiddling with the levels. I've installed the LordSmurf pre-loaded VirtualDub and see a lot of available filters. I guess I misunderstood at first, and thought that the filters were loaded by default. It seems like a jungle, so are there filters which one should always load?

As a sidenote, when I start up VirtualDub I can see in the log that it fails to load 'ffvdub.vdf'. Is that an issue?

The last question is about levels / color correction. I understand that I can get some help from the histogram, but how does it actually work? And should I really care in the recording process or can it always be corrected in post editing? If the latter, is the recommended numbers just smack in the middle at 128 on all?

Thanks all

[lollo2]

Quote:

are there filters which one should always load?

For capturing, none of them

Quote:

ffvdub.vdf

FFdshow, useless for capturing. Almost useless otherwise. Maybe you have a 32-bit / 64-bit conflict

Quote:

And should I really care in the recording process or can it always be corrected in post editing? If the latter

Your card can capture in 16-252 range http://www.digitalfaq.com/forum/vide...html#post62640. You should then set the input levels to capture in that range first of all.
In post process you adjust later levels and color to proper values and/or your personal taste.

[Chanuka22]

Thanks very much for the answer . What do you mean by 16-252 range? I've seen it mentioned many places, but can't figure out what it means and if it's good or bad.
Also, when you say I should set the input leves, are you then just talking about the 'Video - Levels' option in VirtualDub and that I should stay within that range?

[lollo2]

Quote:

What do you mean by 16-252 range? I've seen it mentioned many places, but can't figure out what it means and if it's good or bad.

It means that your card can only capture that range. Not good, not bad, just its feature.

Quote:

Also, when you say I should set the input leves, are you then just talking about the 'Video - Levels' option in VirtualDub and that I should stay within that range?

You should use the procamp of your card (or an external procamp) to limit the source level, providing to the card the range that it can capture. There are several posts in the forum about this topic.

[Chanuka22]

Thanks lollo2, but I must be stupid. I have no idea where to access the proc amp of the card. Is it through VirtualDub?

[lollo2]

http://www.digitalfaq.com/forum/vide...-settings.html

[Chanuka22]

Thanks, we must have misunderstood each other or I failed to communicate the issue. I did everything according to sanlyn's guide, so if you are referring to...

3: Video (top menu - CONTNUED)
Levels...

These are proc amp settings usually linked to the capture device's proc amp controls. Different capture cards have different dialogs and defaults. Some cards don't provide a link that VDUb can use here. Above, typical proc amp for AIW cards.

...then I think I'm all set. I thought there was somewhere else where I had to hard set the limits, but if you are "just" referring to the Video levels within VirtualDubthen all is good. As it is - with my tapes - I can't steer to far off the middle 128 values on brightness and contract before it looks wrong.


Before you answered I came across avisynth and graphedit, and actually thought I had to fiddle around there, but that is for something else?

[lollo2]

You asked:

Quote:

And should I really care in the recording process or can it always be corrected in post editing

and I answered that if you "crush" the blacks (Y<16) or "clip" the whites (Y>252) you cannot recover them in post editing. Then be sure to capture inside the allowed range of your card.

If you want to check with AviSynth a significant segment of your capture you can use Histogram("levels") or ColorYUV(analyze=true)

[Hushpower]

"In my experience"

Don't use VDub filters for capturing. If you do, you're forcing your machine to do possibly intensive processing while capturing, leading to dropped frames.

Definitely set your brightness and contrast levels before/during capturing.

I've found (as has been said on here elsewhere) that the ES-15 tends to brighten up the picture a bit, and on bright scenes, you may get white-out. If the whites are too much, you'll never get the detail in the white area back in post processing/editing. So you've got to keep within the limits (I don't have a great grip on 16 and 235 so I'll just stick with what VDub histogram is telling me).

Here's how you set the brightness and contrast:

Get VDub set up for capturing, as you have been doing.

On the Video Menu, set
-Enable the Histogram (Video>Histogram)
- I also need to set Video>Preview (that is what I need for my card) to get the histogram to show. The black window will appear at the bottom of the video window. You should see some light blue signal colour.

Play your tape. You’ll see the histogram signal jumping around as the scene brightness changes.

To adjust the “levels”, use the Proc Amp/Levels controls (Video>Capture Filter>Video Proc Amp tab). If you can’t (Histogram and video frozen) read below re use of Graphstudionext.

The Brightness slider controls the left end, and the Contrast slider controls the right end. Adjust each to stay within the limits. I set the Brightness first. The limits may be shown by a red mark. Mine aren’t, but if you overcook either then you’ll see the hard limit the card is bumping up against and then you can decrease the contrast or increase the brightness to adjust the level.

I think my card (GV-USB2) only captures 16-235; that’s why there is a black no-go area on each end of the histogram.

Brightness High.jpg

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Brightness Low.jpg


The next issue is if you can’t control the levels while the tape is running, that is, when you go to Video>Capture Filter>Video Proc Amp, the picture and histogram freezes. This can be easily overcome by using Graphstudionext to get access to the Proc Amp, as follows:

Run Graphstudionext (it doesn’t install, just runs)

Graph>Insert filter:

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Scroll down to your capture card>click it (one of the “analogue Capture” entries), click Insert and then close that window:

Correct levels.jpg

Right-click on the grey box showing your capture card, choose Properties, then the Video Proc Amp tab, and you’ll be able to control the levels while your tape is running.

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You can save your Graphstudio arrangement by using “Save as XML…”. That will make it easier to get to next time.

[Chanuka22]

Thank you both, very helpfull

[Chanuka22]

Hi, me again . How should I deal with the red on either side of the blue. Is the goal to have minimal amount of red on either side or no red at all? My own guess would be no red at all. Am I correct in understanding that the red represents the color bleeding outside the 16-252 range, which is why there ideally should be no red at all?

[lollo2]

The reds are for Y<16 and Y>235. With your card you should avoid red for "low" Y, while you can accept some red for "high" Y. To be safe (without additional setting requiring extra processing), just avoid any red and your capture will be ok.