OT-ish: Depth of Field Focus

Grazie wrote on 4/19/2003, 4:05 AM

Hiiyah! Simple explanation of DoF and Shallow DoF

http://www.dvcreators.net/media/depthoffield.html

Hope this is of use

Grazie

Comments

Paul_Holmes wrote on 4/19/2003, 11:32 AM

Nice tutorial. I've been noticing this a lot in TV commercials. For viewing on television, isolating the subject from the background is very effective. Now if I can find where I put that Neutral Density filter . . .

DDogg wrote on 4/19/2003, 2:43 PM

I always wanted to figure out a way to take a video fore-subject and blur the background to simulate a shallow DOF like I can do in PhotoShop with a still. Any opinions of how?

Bill Ravens wrote on 4/19/2003, 5:35 PM

Make a mask, invert it...apply the blur filter to the layer below the mask.

DDogg wrote on 4/19/2003, 6:00 PM

Bill, thanks for the reply. I have a feeling you just cost me a week of tinkering to figure out that one liner :) Off to study up on masks....(never used 'em before). Man, now wouldn't that make a great subject for a tutorial! :-)

vicmilt wrote on 4/19/2003, 10:01 PM

Have used this technique for years in Photoshop, but....
is there a way to have the mask ride with the moving image in a video?
I thought that rotoscoping was the only solution. Has something new come along?????

Grazie wrote on 4/19/2003, 11:49 PM

Here's an example of a mask of the word Floriade. I created this mask by removing the "white" areas of the text - is this what you mean? I use Paint Shop Pro

Grazie

DDogg wrote on 4/20/2003, 7:56 AM

Doing it for video is the question I think.

Imagine a somewhat surreal shot of a person walking in a forest with that person in sharp focus and the background blurred or otherwise altered/colored, etc. Can anybody suggest a method to do this with some details using the original shot (not color keyed separate shots)? It may be impossible given the moving foreground, dunno.

vicmilt wrote on 4/20/2003, 2:05 PM

Exactly -
I believe you can do this in Commotion. It's called rotoscoping,and there's an enormous amount of hand work involved (to do it right), but I don't think it's available (yet) in VV.

SonyDennis wrote on 4/23/2003, 9:17 AM

If you lock down the camera and shoot a clean plate, you can do a "Difference Squared" compositing mode against the footage with the foreground, and it will extract a moving mask, which can then be used for the effects you're talking about. The "Transporter" example (, Sample Projects, Transporter) shows this technique in action.
///d@

DDogg wrote on 4/28/2003, 6:04 PM

SonicDennis, I apologize as I missed this reply. They go by so fast. Thanks very much for this link. I didn't think it "doable"

TeetimeNC wrote on 8/7/2004, 4:29 AM

I would like to learn more about moving masks. Is this sample project available at a new location?

Randy Brown wrote on 8/7/2004, 7:05 AM

Is it just me or does SonyDennis' link not work?
Randy

MyST wrote on 8/7/2004, 7:08 AM

I did have problems reaching FTP sites before, but found a fix.
This site however, I can't get to either.

Mario