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dmk75
08-25-2004, 08:54 AM
Is there any way to do auto color correction to all clips in a time line? May be during capture or after?

Thanks
Dmitry

Jim_C
08-25-2004, 09:00 AM
During capture use the proc amp built into the switcher to color correct any input.
After capture, In VT-Edit, make color correction to one clip, save as Tool Shed Preset, select all other clips and apply tool shed preset to them.

dmk75
08-25-2004, 09:22 AM
What about capture from tape via FireWire? Is ther anything that can be done?

Thanks
Dmitry

Jim_C
08-25-2004, 09:47 AM
Use the procamp on the switcher.
Drag the DV symbol on the switcher bus on to the proc amp designation and adjust.

ScorpioProd
08-26-2004, 12:54 PM
I don't think Dmitry means for live switching use. So the answer is no.

Adjusting the proc amp will NOT affect a DV capture via firewire one bit.

A DV capture via firewire is a file TRANSFER, it is not really a capture, so you can't alter it at all.

Jim_C
08-26-2004, 01:00 PM
>>Adjusting the proc amp will NOT affect a DV capture via firewire one bit.

Actually it will.
I just did it. (here we go again ;) )

DV Deck into firewire card. DV punched up on to switcher as input. DV set to input on proc amp built into switcher.

Press record, turn dials on proc amp in real time, you can see adjustments being made on monitor and adjustments are there on recorded file also.

So unless we are speaking of different types of capture, you can adjust DV input via proc amp thru switcher.

Jim_C
08-26-2004, 01:09 PM
OK, figured out the yes/no of it.
Using Main In to record, which I guess is direct transfer, no proc amp control.
Use Prog out to record and you can adjust with procamp all you like.

I checked recorded color bars captured unaltered thru main in and prog out and I see no difference, so I do not belive you are losing any direct transfer quality using prog out.

So if you need to tweak your DV footage while recording, it is available.

bradl
08-26-2004, 01:42 PM
...prog out and I see no difference, so I do not belive you are losing any direct transfer quality using prog out.The Prog out method actually triggers a decode then a re-encode of the DV footage.

Jim_C
08-26-2004, 01:50 PM
The Prog out method actually triggers a decode then a re-encode of the DV footage.


And does this procure a quality loss?

ScorpioProd
08-26-2004, 04:08 PM
Definately a quality loss.

Is it something that anyone would necessarily see? No.

Thing is, DV is a lot better codec than a lot of people (like Newtek in the "compression sucks" era) would like to believe.

And I've quoted white papers before about how the inital DV compression is where most losses occur, and losses after that are minimal, assuming you're not doing major changes to the video, color correction not being a major change in the sense of this statement.

The more important problem is that if you go through this uncompression of the DV into the switcher in order to do this type of color correction, it is not realistic to expect that you can then compress it back to a DV codec all in real-time without any problems. This is asking too much of even top machines. Saving it to uncompressed RTV after the color correction is a viable option, but you need to have the space available, of course.

chribba
08-26-2004, 04:45 PM
Thing is, DV is a lot better codec than a lot of people (like Newtek in the "compression sucks" era) would like to believe.


I would not agree that DV is a good codec for broadcast, maybe for semipro productions but not for proffesionals. Currently we are using "professinal DV" at our station and it sucks.... Speaking of pixelproblems.. Try to shoot a forest with a lot of leefs, and the DV will give you a really bad picture... And wideange pictures of contyside is really bad, blur picture (or maybe thats an FX for free). This is in PAL and i dont know if NTSC has the same problems with less lines...

Chribba

ScorpioProd
08-26-2004, 11:44 PM
NTSC has the same problems in DV, but it's just what has won in the format wars, even at a professional broadcast level, so it's what we all have to live with.

I agree that DV has the problems you mention, but I meant that if your source is already DV, which it is since he wanted to firewire it in, the additional decompression/compression cycle probably wouldn't make a visible difference.

As for in the broadcast industry in my area, we have four local news stations. Three of them are DVCPRO25 and one is Professional DV. They are all going digital and upconverting these sources for HDTV.

chribba
08-27-2004, 03:57 PM
Speaking of generation loss made me remember a test that was made some years ago. Feel free to check it out.. If DV gives generation loss or not when decompression/compression is up to everyone to them self to decide.

http://www.adamwilt.com/pix-codecs.html

chribba

ScorpioProd
08-27-2004, 06:41 PM
Happily, those codecs have since been surpased in quality.

radams
08-28-2004, 05:41 AM
Okay guys,

getting back to the original topic of CC...

To auto correct a project or selected clips...

Two of several easy ways...

Go to one of the clips that you want CC'd this will be your basic CC adjustments that will be reproduced across all of the clips you want. Then open toolshed and save this as a preset...Make certain that you have selected all of the needed parmeters to show in splines...SO now you have a preset in toolshed for you adjustments...

Go and select all of the clips you want to have this adjustment (you could select the WHOLE project)..the apply your preset from Toolshed..Now also note that this will also work on sub projects as well...Also if you are trying to match clips from one reel to another...just correct to the reel you want...then select all of the other reel's clips and apply your CC..nice and quick...and you can then go in and make more adjustments afterwards per clip or over several thru presets ;)

Cheers,

Ray Adams

Jim_C
08-28-2004, 07:06 AM
During capture use the proc amp built into the switcher to color correct any input.
After capture, In VT-Edit, make color correction to one clip, save as Tool Shed Preset, select all other clips and apply tool shed preset to them.
Z

You mean kind of like this suggestion. The first response in the thread.

bradl
08-28-2004, 11:05 AM
Is there any way to do auto color correction to all clips in a time line? May be during capture or after?

Thanks
DmitryAnd one last way that has not been mentioned and may actually answer the original question the best:

Drop the Color Correction effect filter (Effects folder) on the Timeline and drag it out to cover all the clips you want to CC. Adjust in Control Tree or Edit Properties.

This method has obvious disadvantages and I don't use it much, but if all your clips need the same CC applied it can be nice as you can tweak it over and over while checking its effect across the entire project.