Comments

HeeHee wrote on 8/23/2002, 1:58 PM
That's the nature of video displayed on a computer screen. If you intend the production to be for internet or computer use only, then you can apply a brightness/contrast or similar filter fx to the event. If it is intended for viewing on a TV, then leave it alone if it looks fine there.
Control_Z wrote on 8/23/2002, 6:13 PM
I agree. This really belongs on the wishlist for VV4 - ability to adjust preview gamma.

I can do it now with Powerstrip, but that brightens the whole screen, making it hard to look at. Maybe just an option to skin VV3 to darker shades.
salad wrote on 8/23/2002, 10:46 PM
Would like to thank Fuzzy for this post cuz I just got done tweaking some DV clips bright/contr. and better send to xternal TV monitor now to check adjustments, I sometimes tweak too far. Thanks for the reminder.
Been playing with color curves plug for this. Chienworks, wasn't that you who pointed this out? Thanks, cuz this IS a very, very nice plugin to play with for such type of adjustments, and other crazy stuff too....
Screen res now at 1280 x 960, this seems good, but had to graduate up from 1024. Preview window smaller now, so maybe Cntl_Z's idea of a gamma adjust is a good one.

Thanks
BillyBoy wrote on 8/25/2002, 11:36 AM
If your final target is to play some video off a DVD player and view on a TV, then only edit and adjust while viewing off an external monitor. You don't really need anything fancy, any TV (properly adjusted) with video in inputs works good.

Besides the color curves FX filter, also use the Levels and HSL filters. There is a interrelationship between them which means you'll need to adjust one, then perhaps adjust the others, then go back again to get things exactly the way you want them.

Personally I find the presets on the color curves filter too extreme. It is a simple matter to make custom filters, and use those instead.

A little trick I use all the time:

If you haven't already break you source files into scenes, especially important if there are major changes in lighting. Open a filter, for example Levels. Start with gamma. Set the first key frame to a value you know is slighly too dark, then jump to the end of the event and set a value that's slightly too bright. Play the event. The key here is the scene before starting should be roughly the same lighting levels.

Now start playback. You'll see a gradual increase in the overall brightness. Once you see the ideal level, stop the playback, note the settings. Now reset the keyframes making the start and end values the values that looked best. For example if you've discovered that 1078 works, that's what you enter in the first and last key frames. If you've set other key frames in the event, be sure those are charged as well to avoid a rollercoaster effect of the brightness going up and down. Just use the next key frame arrow to walk through the event, carefully noting the values as you go along and changing as necessary.

By doing this simple procedure you've automated the trial and error process and stepped through a whole range of adjustments in one simple operation. Repeat as needed for each filter.



salad wrote on 8/25/2002, 1:01 PM
Thanks BillyBoy,
I am memorizing this now.
Yes, prests for colorcurves too stong(ex: the "increase contr."), maybe just there to show what can be done? Can't use them.
Xcellent!
BillyBoy wrote on 8/25/2002, 4:24 PM
My opinion is the color curve filter is better used if you make a more traditional "S" curve. I've written a few posts on the topic here. Can't find them just now, so here goes again...

Theory:

Any image, still or video, can be divided into three rough areas, shadows, midtones, and highlights. A filter like brightness and contrast effects the whole image equally, so you're likely to either over do or under do some portions of the image. The result frequently being 2/3 of the image is either over done or under done. The better way is to use color curves which allows different levels of adjustments for shadows, midtones and highlights.

If you drag the color curve filter to the timeline without selecting any preset you'll notice there is a single diagonal line across the grid from lower left (shadows) to upper right (highlights).

For an idea what a "S" curve is suppose to look like check out the linked page below, which while intended for Photoshop, still in principle applies to what I'm explaining. The one I'm going to describe in detail increases contrast. To reduce contrast simply reverse. Other curves can also be applied or just make them move severe in slope.

http://cit.asma.ru/Photoshop/Help.htm

You begin by moving the center point (add if necessary) which should be eyeballed to be located at the middle of the graph. Drag this point upwards and in an arc to the left and top in one motion as you hold down the mouse button. Notice the effect. How the middle portion of the line moves much more than it does at either extreme. For a somewhat washed out image you probably want to move the center point up and into the next grid box up and to the left of the middle so it is roughly in the lower right hand corner of that grid box. This adjusts the midtones. Swing it in an arc to see the effect.

Next establish a point near the middle of the lowest left grid box ay the extreme lower left of the grid to adjust shadows. Once you set a new point, You'll want to move this point down and to the right, again in one motion while holding down the mouse button. To adjust highlights add a point near the center of the top most grid box at the extreme top right. Drag to top and left. When done you should have something approaching what looks like a flattened "S", hence the name. How much you drag the set points and where you place them, depends on how much adjustment you need. For more extreme adjustments move the shadows and highlight set points closer to the center of the graph so the arc is more extreme. Every video is different and even varies from scene to scene. You just got to play with it. A little goes a long way. Make minor adjustment. Note that once you establish set points you can adjust specific areas in the image without messing up other parts. The beauty of curves.

The result should 'pull out' a richness and depth from the image that was there all along but hidden without the harshness of applying either brightness or contrast to the whole image which is the sledge hammer approach.

What I've done is create a bunch of "S" curves, covering a wide range of common adjustments. Then all you need to do is drag any of your custom presets and most times you won't have to fiddle with it, making any fine tuning using Levels and HSL, etc..