View Full Version : clip about cineframe 24 converted to 24p


Gabriele Turchi
October 26th, 2004, 03:39 PM
What do you think about it?:


http://70.56.179.231/cineframe24.html


Best reagards


Gabriele

Chris Hurd
October 26th, 2004, 07:22 PM
Just an FYI, the page you're linking to was written by one of our members, Lorin Thwaits.

Lorin Thwaits
October 28th, 2004, 12:03 AM
The same sample plus other uncompressed frame grabs is now available from here:

http://www.couponmeister.com/cineframe24.html

-Lorin

Joonas Kiviharju
October 28th, 2004, 12:44 AM
Lorin Thwaits wrote in http://www.couponmeister.com/cineframe24.html
"Each frame is still recorded progressive by the camera, so you don't lose out on any resolution by using this effect. (No cheap line-doubling going on here as is done with the "progressive" mode of Sony's DV cameras.) The variation of timing between frames is the only thing a little hokie here"

I still don't quite understand how Cineframe works, but as Lorin Said it doesn't double the fields, and it gives you the full resolution. The real problem is the 1/60 shutter speed.

So, I was wondering about the PAL version of the camera. It does a 50i picture, so the slowest shutter speed on Cineframe25 should be 1/50 - which is the correct speed for a proper filmmotion with 25 frames.

I tested the camera for a couple of minutes, and I quickly went through the preproduction models menus, but I couldn't find the Cineframe, but my dealer says that the final version has Cineframe25.

If Cineframe really loses no resolution, so what makes it not to be really progressive on the PAL model? If the chip is not progressive, then there should be a time difference between the fields in a frame? And then you'd have to do some blending or other deinterlacing to get rid of it? So how exactly does the Cineframe25 work on the PAL model? Does anyone know that yet?

Barry Green
October 28th, 2004, 10:54 AM
The problem with CineFrame 24 (if there even is a problem) isn't the shutter speed, it's the sampling frequency. Film cameras shoot at 1/60 all the time, and it still looks plenty like film. Any camera with a 144-degree shutter (such as the original CP16, the Auricon TVT, and many others) shoot at 1/60.

The problem is that with CineFrame 24, the samples aren't gathered at evenly-spaced intervals, which is how film or 24P would do it.

With CineFrame 25, they are. Every 25th of a second you get a new frame update, which is close enough to film to "count". CineFrame 25 should look quite filmlike.

It's too early to tell whether CineFrame 24 delivers "the goods" or not. We're going to have to test it against real 24P to see how the motion holds up.