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-   -   how can i fake widescreen? (https://www.dvinfo.net/forum/open-dv-discussion/18732-how-can-i-fake-widescreen.html)

Patrick Falls December 23rd, 2003 09:08 AM

how can i fake wide angle?
 
hello everyone, i have a canon xl1 and i was wondering if there was a way i can fake wide angle? i was wondering if i can do it in post or something of that nature? i haven't really grasped the full understanding of wide angle other than it fits more in the frame, and if that is true can i just zoom out of my subject to achieve the same effect and in post crop it the way that it would be with a wide angled lens? i know that i'm guessing i will lose resolution, but are there any articles on this sort of thing?


thanks in advance

Boyd Ostroff December 23rd, 2003 10:19 AM

I'm guessing that you mean "widescreen" instead of "wide angle"?...

Dan Uneken December 23rd, 2003 02:02 PM

Hi Patrick!

I think you will enjoy a good book on the basics (and more) of video and cameras in general. I find the following book very useful:

"Today's Video" by Peter Utz

It explains everything from how a TV works, cameras, lenses (wide-angles, tele, depth of field, focus etc.). It's just too much to explain in a forum.

Enjoy your XL-1: it's awesome!

Rob Lohman December 23rd, 2003 02:10 PM

If you are after a widescreen effect then this is called letter-
boxing if you do it in post production (after the material has
been shot). Most editing applications can do this (like Vegas
and Premiere on the PC).

Patrick Falls December 23rd, 2003 06:57 PM

thanks everyone
 
ok i may have wide screen and wideangle confused. ok, 16:9 on a 4:3 television will give you the letter boxed effect right? on a widescreen tv the letterbox won't show up, so most people do it just for the film like effect for 4:3 tubes?


how does a clip shot with a wide angle lens differ from a clip shot with a regular lens? i apologize if my questions seem a little confusing. i'm new to filming and i've been reading a lot on this field. i apreciate all of the help i have been given from everyone.

Dan Uneken, i will look into that book that you mentioned

Boyd Ostroff December 23rd, 2003 08:09 PM

A wide angle lens merely expands the field of view from what a "normal" lens would show. There's no way to do this in post since it has to do with the camera's angle of view. But the whole notion of "wide angle" and "normal" is pretty subjective in the first place.

Now the widescreen effect is something entirely different and has to do with the ratio of the image's width to height, known as "aspect ratio". In the era when television began eating into film audiences the studios needed something special to get people back into the theatres, and the idea of a wider screen was born. For a fascinating history of this you might want to visit the American Widescreen Museum

Patrick Falls December 24th, 2003 08:40 AM

thanks Mr. Ostroff
 
from what you stated about the wide angle lens expanding the
field of view, isn't that like zooming out to expand the field of view? i have not seen any wide angle shots compared to normal view shots so i'm just trying to imagine the concept. so are the advantages of a wide angle lens is to get you a closer shot with a wider view, rather than a zoomed out shot with a wider view? i'm assuming if zooming out and then cropping in can get you the same look, but just at a lower resolution, is this correct?

Boyd Ostroff December 24th, 2003 09:35 AM

Your zoom lens goes from "wide" to "narrow" at opposite ends. Somewhere in between is what we would consider "normal". Like I said, that's very subjective, but you might think of "normal" as roughly equivalent to a human field of view.

So if you zoom all the way out it should actually be a moderate "wide angle" view. However a true wide angle lens will expand the field of view even further. Imagine that you are looking at a row of ten fenceposts that are numbered like this:

1 2 3 4 5 6 7 8 9 10

Let's say you point your camera so the middle of the picture is between the 5 and the 6. Now you zoom your lens all the way in. On the left side of your picture you see the 4 and on the right side you see the 7. All the other posts are outside of the field of view. Now zoom out to a more "normal" view. Now on the left side you see the 3 and and on the right you see the 8. Now zoom all the way out and you see the 2 of the left and the 9 of the right.

In this example, you didn't even photograph the 1 and the 10 because they were outside of your field of view. So there is no way to "fake" a wider view after the fact because some of the information is missing. But now if you change to a wide angle lens (or add a wide adaptor to your regular lens) your field of view gets wider. Now you actually will see post number 1 on the left and post number 10 on the right. This is a simplistic example, but hopefully it illustrates the point. You can't create information that wasn't there in the first place by cropping.

Again, you're confiusing widescreen and wide angle I think. With the wide angle lens the overall size of the picture frame stays the same, it just contains more information and shows a wider field of view (in other words, everything will look smaller). By cropping you would be changing the size of the picture frame itself. That's something completely different than using a wide angle lens.

The widescreen effect, as it was originally conceived for Hollywood movies, was accomplished using specialized optics which squash the image horizontally. Then when projected another lens was used to stretch it back out, resulting in a picture that is the same height as a normal screen but is wider. These special lenses are not called "wide angle lenses" but are called "anamorphic lenses". The term "anamorphic" comes from the greek words that mean "changed form".

Hope this helps. Take a look at that website I recommended before to see examples of anamorphic lenses. They are completely different from wide angle lenses.

Glenn Chan December 24th, 2003 02:33 PM

When you get really wide (i.e. <21mm in 35mm camera terms) then perspective is "distorted" and you get a kind of special effect from it. Also, because of lens design wide angle lens usually have some optical defects like barrel distortion.

http://www.photo.net/making-photographs/lens Just go look at some pictures (scroll down to wide angle on that site)

Patrick Falls December 24th, 2003 03:32 PM

Cool
 
got it, i followd the link from Mr. Glenn Chan and it explained it to me as well as the detailed example from Mr. Boyd Ostroff. so, if i have this right, a wide angle lens squeezes more into the frame. i guess that's why a lot of music videos use them, am i correct?

Boyd Ostroff December 24th, 2003 03:46 PM

The wide angle lens will let you see more without getting farther away from the subject. As Dan notes, this may involve a certain degree of distortion. But wide angle lenses used in close proximity for facial closeups are not usually a good idea. They will tend to make the subject's nose look large and give their face sort of a distorted goofy look. For a more flattering portrait, back off a little and zoom in as needed.


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