View Full Version : 3K at 45FPS? (Or how I learned to window a sensor to death)
Evin Grant
03-15-2007, 02:13 AM
Ok this is a little out in left field but bear with me...
If it's possible to window the sensor to 2k and achieve twice the frame rate would it be concieveable to window less, get more resolution but still get more overcranking as well? Personally 60FPS is great but more often than not I'm overcranking at 48FPS or less. So I would love an option that allowed me to overcrank to say, 45FPS at 3K RAW (50% more speed 1/2 the image data of 4K 30FPS). Yea, I know it's a non standard res but it would mix into a 4K project better than 2K upres (2x the pixels) and it would allow for more post options (Stabilization, re-framing ect.) in a 2K workflow. Not to mention the DOF benefits of shooting a larger, if not quite 35mm sensor area. You would be shooting RAW anyway so either an up-res or down-res could probably be handeled in Redcine no problem. Anyway, I'm sure it's a big hassle and I'll keep my mouth shut from here on out.
Mark Pugh
03-15-2007, 03:08 AM
sounds smart to me - that's what the phantom HD can do - and all sorts of aspect ratios as well - you can set the format to 2.35, for example, by customising the height of the sampling from the sensor. with the red at present, you'd be working with a higher than necessary data rate to achieve that ratio, because you'd have to throw some of the picture away anyway. and yep 48 would be a common speed... in the PAL world where I am 50 is also more common than 60, so a larger format 50 would be great...
Jeremy Hughes
03-15-2007, 05:46 AM
And of course you can always use RED-RAID to get 45fps at 4K. Then in REDCINE you could convert it into REDCODE.
PaulClements
03-15-2007, 06:29 AM
I think Evin's point was using the RedDrive in order to overcrank ocular.
I also agree with mark if you could crop the sensor to be closer to 2.40 it would also be another means of lessening the ammount.
I posted this resolution chart over at DVXUser a while ago:
http://www.dvxuser6.com/uploaded/17514/1162935832.gif
And if my maths was correct (which I'm fairly sure it was) you can see that 4k 16:9 has 2414336 more pixels than 4k 2.39:1. Which equates to almost a quarter less information passing through the sensor. Theoretically speaking you ought to be able to shoot Digital Cinema 4k at 2.39:1 at 45fps using a RedDrive.
Interesting, would like to hear Graeme, Jim or anyone on the Red teams comments on this.
Sam Druckerman
03-15-2007, 06:49 AM
I love this thread.
I remember a while back there was talk about cropping the active pixels to 2:35 for higher frame rates.
But, the idea fell away, I don't remember why.
So, before I get to worked up about this...
Can someone from Red comment on if it's possible to crop the active pixels to 2:35?
I sure hope so.
C'mon guy's.... how about one more rabbit out of the hat, Pleeeeease.
MikeCurtis
03-15-2007, 08:08 AM
Not that I know the details, but my GUESS is that something like this could be possible - I'd chimed in on that 2.35 aspect ratio thread - but how about we let them get the basic camera out, shipped, working in the field with any 1.0 bugs worked out, etc., and THEN start worrying about optimizations from there...
Jim Arthurs
03-15-2007, 08:18 AM
Crazy me, I'd like completely customizable windowing... I've actually got a use for a square area that is defined by the height of the sensor.
However, if it doesn't help with higher frame rates when you do this, and since the black areas (I'm assuming) under REDCODE compress fully, then maybe not...
Noah Kadner
03-15-2007, 08:34 AM
I think Evin's point was using the RedDrive in order to overcrank ocular.
I also agree with mark if you could crop the sensor to be closer to 2.40 it would also be another means of lessening the ammount.
I posted this resolution chart over at DVXUser a while ago:
http://www.dvxuser6.com/uploaded/17514/1162935832.gif
And if my maths was correct (which I'm fairly sure it was) you can see that 4k 16:9 has 2414336 more pixels than 4k 2.39:1. Which equates to almost a quarter less information passing through the sensor. Theoretically speaking you ought to be able to shoot Digital Cinema 4k at 2.39:1 at 45fps using a RedDrive.
Interesting, would like to hear Graeme, Jim or anyone on the Red teams comments on this.
very cool- can you put NTSC 480p in there too?
-Noah
Jay A. Kelley
03-15-2007, 08:36 AM
I'll lay my money down on a big fat "NO" or at least a "NOT RIGHT NOW" from the RED gang.. But that's just me. I'll be happy if I'm wrong since you all want this.
Jay
P Andersson
03-15-2007, 09:10 AM
wonderful that this keeps popping up
higher framerates adjusted through variable cropping and aspect ratio
could do something more adjustable with higher compression and super high iso as well where it is up to the user to degrade the image a bit just to get the shot. If you want to get 120 fps in the evening, maybe a bit of aspect ratio crop of the sensor would lift if from 720p, a little higher iso would take care of the light and slightly more compression would let you get the shot down to an acceptable bandwidth for the drives
I do respect if they only make the camera work as long as the image is all clean, it is a choice, instead of getting a slightly noisy picture, you simply have to find another solution,
but even if we had the finest kodak emulsion, we could always push it a little, knowing we would get contrast, grain and lose shadow detail and perhaps crush some of the highlights, we could
PaulClements
03-15-2007, 10:56 AM
very cool- can you put NTSC 480p in there too?
-Noah
Hi Noah,
I only put those resolutions on since they are the ones supported by the camera.
I don't think 480p is so it's value isn't too worthwhile being on there since the sensor size doesn't window so low. It would only be worthwhile as an example and I'm too lazy right now to find the original file and do it :)
Paul
PaulClements
03-15-2007, 11:01 AM
Another one... if 16:9 2k is 2359296 and 2.39:1 2k is 1757184 that means each frame carries 75% of the data, if it was possible to compensate pixels for framerate it ought to be possible to do 75fps+ at 2.39:1 2k without a RedRaid