HD Waveform - CinemaScope, Zoom Versus Anamorphic

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Richard
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HD Waveform - CinemaScope, Zoom Versus Anamorphic

Post by Richard »

This is an exciting time for home theater and one for which I have been waiting; the ability to properly display CinemaScope content in its native aspect ratio, duplicating the experience of your local film theater where CinemaScope content is larger, growing left to right as the side curtains are pulled back to reveal more screen for a larger image.

Check the A/V and videophile magazines for this year. Odds are quite high that they had advertising for cinemascope screens, lenses or compatible projectors. A new term has appeared in front projection reviews and specs called "Panamorph lens compatible/capable", which was also supported by...

[url=http://www.hdtvmagazine.com/columns/2009/07/hd_waveform_cinemascope_zoom_versus_anamorphic.php]Read Column[/url]
videograbber
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Post by videograbber »

Is there some reason why attempting to look at the OAR2.jpg picture embedded is popping up a Password Request box (when I'm already logged in at hdtvmag)?

- Tim

P.S. The above problem has now been fixed, thanks.
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Post by videograbber »

Richard, thanks for an interesting article.

There are a couple things I need to point out though. Re: anamorphic 2.35...
> The black bars of a 2.35 source prevents about 33% of the pixels from being in play reducing vertical resolution to about 482 pixels or lines for 720p so being able to recover them is clearly a good thing <

This is a common mistake. Using the full field at 1.78 does yield 33% more vertical height than 2.35. However, going in the other direction, 2.35 is only 25% less. So you'd actually have a vertical rez at ~545, instead of 482. Another way of confirming this is that 2.35 uses 75% of the available height (not 67%). However, that doesn't change the point you were making... just the numbers.

Re: zooming 2.35, there's a similar, and compounded, issue...
> You are making the image 33% larger so light output will drop by about 33%. <

Making the image 33% larger would drop light output by only 25% (to .75 original). It's easy to see this if you think about what would happen if you made it 100% larger (double)... light output wouldn't drop by 100%! It would only be 50%. But the compounding comes when we realize that the zooming is occurring on both axes. So the light output would be reduced to .75 x .75 of the original, or 56%, for a 44% loss.

~~~

I'm looking forward to the day when these new-fangled digital projectors have all the parameters associated with zooming fully automated, and the PJs have sufficient zoom range and iris control to maintain uniformity over a significant operational lifetime. In the meantime, I'll continue to use my 3-eyed monster, which also gives me the flexibility to operate in CIA mode, which I prefer to CIH (both superior to the conventional CIW by a large margin).

I would have to take issue with one statement:
> Regardless, consumers and retailers alike have nothing but praise for the ability to fill out a 2.35 screen with all content getting black bars off of the screen! <

While I am sure this is true for many consumers and retailers (sadly), it is not for all. Some (such as yourself) recognize that the art is more important than the frame, and not vice-versa. Luckily the Mona Lisa came in her own frame, since if those folks were left to their preferences, they'd hack off parts of the painting to make things fit with whatever frame they had on hand. Some would even like to say there should only be _1_ shape of frame, and everything should be made to fit _it_. Hopefully, someday these folks will see the light, though it seems unlikely at this point.

- Tim
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