Thanks jrazz.

I'll give it a try.

Let us know how it works out, but I don't really hold out much hope for you.

Grad filters generally cut about 2 to 3 stops of light at the darkest part of the filter (the sky). Even digital video won't really hold that kind of luminence spread..

What would be FABULOUS would be to shoot your scene two times. Once exposing for the sky - once for the land. Then grab a freeze of either one. Import it into Photoshop and create an instant BW mask.

Use the mask in Vegas and adjust it's intensity by using a track video effect "levels" to join the two together.

Of course, this will not work handheld (ha ha - wow) or where there is any camera movement at all, like pans or zooms. But for sunsets, it should be great.

In fact it sounds so good, I'm going to try it myself in the next few days.

This is a technique I do all the time in still photography. Anyone ever try it out???

v

Try this (similar to jrazz' idea, but more complicated :D ):
Make a new video track. Set composite mode to multiply. Make this a parent to the track below (otherwise the effect applies to other tracks, and you dont want that).

Apply the color gradient filter.
Point 1: Make this any color. Play around with this color, especially in HSL mode (which is more intuitive). The colored button with the color patches flips from HSL to RGB color picker and vice versa.
Point 2: Change this to 255 255 255 RGB.

Change the position of the dots around.

http://glennchan.info/Proofs/forums/sony/nd-grad.veg

2- Vic:
People nowadays at taking like three exposures and slapping them together into a high dynamic range image. Basically you get detail practically everywhere.

The problem with HDR images is that you need to make them into a lower dynamic range. If you just multiply them by a number <1, then the image will look lacking in contrast and saturation and will look really boring. So there are various ways to map all them dynamic range into something that can be displayed. One simple method is to apply the curves and make it s-shaped. You can also paint in additional detail and such (manually) by combining the exposures differently.
Film in a way is a form of HDR. It has its own look though in its color response.

3- The high-end digital cinema cameras let you capture more than normal dynamic range. On the horizon, Red will allow that too.
At the low end, the andromeda-mod to the DVX100 allows this too.

Other cameras apply video knee, and may let you adjust the gamma curve / transfer function (i.e. DVX100, HVX, some of the prosumer cameras that came after them).

Some cameras can be tweaked to capture additional exposure latitude via their gain settings. Usually only broadcast stuff lets you do this, not the prosumer stuff. I played around this a little bit, although this reveals some of the camera's problems (the colors shift).

This is the same idea as HDR in photography. And you could call this HDR too.

Even digital video won't really hold that kind of luminence spread.
It's because the camera manufacturers usually don't let you tweak the camera settings. The Andromeda-mod to the DVX100 shows that the CCDs capture a lot more dynamic range than what you can actually record.
Cameras like Red, Viper, Origin, D20, etc. etc. are on the right track... they will let you change the important camera settings and/or simply record the image without any image processing.

<<<CCDs capture a lot more dynamic range than what you can actually record

Good point, Glenn. I use an older sony CCD monochrome DV chip in an astronomical camera and that records a depth of 16 bits. Sony chips are very popular for this purpose, one good reason being low noise, and current astro cameras using more modern chips still provide 16bit well depth.

Clear blue sky will chroma key quite nicely, just add a new sky!
Apart from the limited dynamic range of the recording and display devices I suspect even if they could handle the dynamic range there's still an issue, you can well exceed the ability of the eye to cope. Grad ND and all manner of complicated variance of them are still used when shooting film. The other way to keep some detail in sky is to use a polarising filter.

Bob.

Serena:
That's very interesting about that use for astronomy purposes.

Bob:
Apart from the limited dynamic range of the recording and display devices I suspect even if they could handle the dynamic range there's still an issue, you can well exceed the ability of the eye to cope.
What do you mean by that? Our eyes have no problem with typical displays (with typical dynamic range; that is, very low).
The trick is making it look "right".

The trick is making it look "right".

Exactly! And what IS right?

The dynamic range of human vision is in the literature -- I must try to find that. Its very much greater than any method we have for recording images.

EDIT: actually no single number, because it depends on the dynamics of the scene and the way it is taken in. In a fixed stare at a point the brightness range is about 100:1, but as soon as the eye moves to scan more of the scene (as you must to see even a TV screen) the dynamic capabilities of the eye can take in a very much greater brightness range (100,000:1). So the fixed stare (no movement of the eye) is equivalent to about 7 bits and about 17 bits in scanning.