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View Full Version : Slow Motion in 2.40:1 4K Redcode Raw?



Jaime Vallés
05-08-2007, 02:01 PM
Hello, all. This issue has been brought up before but I just wanted to present it again in it's own thread. Since the RED team is able to improve the camera via firmware upgrades, I just wanted to put this in their minds for any future updates they might release. Also, I understand that this might seem like the whole "give a mouse a cookie and he's going to want a glass of milk" kind of greed. Well, it is. RED has offered us the impossible, and we are all very grateful. But now we want the proverbial glass of milk, A.K.A:

60p overcranking for slow motion.

I think it's safe to say that overcranking in 4K Redcode RAW is probably going to be the single most requested feature for the RED-ONE after it starts shipping. Currently, we can only achieve 60p in 4K using the RAW port and what will likely be a ridiculously expensive non-portable RAID setup. Fine for David Fincher; not so practical for Joe Indie Filmmaker. Most everyone will be shooting 4K Redcode Raw, which goes up to 30p maximum, due to the limits of the compression chip on-camera.

However, 60p is possible in Redcode RAW in 2K windowed mode and in 1080 RGB (downscaled from 4K), and 120p is possible in 720 windowed mode. So windowing (cropping) the sensor allows for faster frame rates.

This brings up the question:
If we shoot in 4K Redcode RAW, is it possible to crop the sensor to an aspect ratio of 2.40:1 (cinemascope) and achieve frame rates faster than 30p?

Some of this was addressed in a post over at DVXuser (click here (http://www.dvxuser.com/V6/showthread.php?t=77117&page=13&highlight=Slow+motion)), but that was many months ago, and things have changed since then. At that point, it was basically stated that in order to get overcranking above 30p, one should shoot in a smaller format (1080 RGB at 60p) and then upscale in post.

I'm not good at the pixel math, but it seems to me that shooting 4K cropped to 2.40:1 would allow for slightly faster frame rates. Even if it's just 48p (which is 50% slo-mo) it would be fantastic for narrative feature work. I love the idea of working in a RAW environment, and shooting 1080p RGB for slo-mo when the rest of the movie is in 4K RAW seems like it would make the image quality take a hit for those precious overcranked money shots.

I don't know... Maybe I sound like a spoiled brat. :biggrin: I completely support the efforts of the RED team, and everything they've accomplished so far. I'm extremely grateful for the camera they've built, and can't wait to get my hands on #791. But I know that the detractors of RED are going to jump at the chance to bash the camera for "no onboard slo-mo without compromising image quality". If there's anything that can be done to address that concern (even through a future firmware update), it would make a lot of filmmakers happy. Just putting it out there in the "suggestions" box.

All the best!

John Allardice
05-08-2007, 03:23 PM
if you just look at the straight math (number of pixels processed per second, as a rough bandwidth estimate) the hard 2.40:1 crop would give you a potential fps of 40.5
This uses the same bandwidth as 4K 16x9 at 30fps.
It's be lovely to think that we could squeeze another 8 fps of processing power in there somewhere.

Michael Ragen
05-08-2007, 03:36 PM
If 48 isn't possible, I would still be very very happy with 36 fps at 4k. It has become my new favorite framerate. Of course I might have a different favorite if I had access to a Phantom (I'm working on that though).

Yaque Silva-Doyle
05-09-2007, 01:33 AM
If one were to shoot @ 1080p given the current data rate of the red would the software allow for high speed shooting above 120 fps?

Rob Lohman
05-09-2007, 03:35 AM
No, sensor max is 120 fps.

Obviously we'll try to improve the camera with new firmware updates. For now we're gonna finish it first ;)

Finner
05-09-2007, 09:06 AM
Rob or Graeme is a faster then 30 fps 4k redcode raw theoretically possible in the future with firmware upgrades or is it a hardware thing that bottle necks the fps speed? For music videos 48 fps is virtually a requirement so 4k redcode 48fps would be very helpful. I am just really interested to know what part of the camera holds back the speed?

Thanks

Rob Lohman
05-09-2007, 09:18 AM
The compression sub-system is holding that back. We'll see how far we can take the current system :)

Finner
05-09-2007, 09:43 AM
Thanks Rob,

48fps would really be great. I know people would want more but 48fps would give everyone at least a decent slo-mo speed.

Joe Aurili
05-09-2007, 09:58 AM
I think 4K 60FPS in REDCODE would be incredible useful for oversampled 1080p work if at all possible. Even if the compression quality was reduced (just for this mode) to a degree to achieve the rate. When downsampled the extra speed should more then compensate for the compression difference visually.

Jaime Vallés
05-09-2007, 10:04 AM
I think 4K 60FPS in REDCODE would be incredible useful for oversampled 1080p work if at all possible. Even if the compression quality was reduced (just for this mode) to a degree to achieve the rate. When downsampled the extra speed should more then compensate for the compression difference visually.
This actually IS possible. Shoot in 1080p RGB at 60FPS downscaled from 4K on the fly in the camera. If your target is 1080, you can get oversampled slo-mo right off the bat (once Redcode RGB is up and running, I presume).

Joe Aurili
05-09-2007, 10:13 AM
Sure, but Jim said "RGB sucks" and to shoot in REDCODE RAW :)

And I have to agree after all I have read.

But, for limited slow mo sequences, it might be just the ticket.


This actually IS possible. Shoot in 1080p RGB at 60FPS downscaled from 4K on the fly in the camera. If your target is 1080, you can get oversampled slo-mo right off the bat (once Redcode RGB is up and running, I presume).

Yaque Silva-Doyle
05-09-2007, 07:22 PM
Thanks Rob, no worries just thought that I would ask. I am more than amazed at the camera's current capibilities and want to thank you guys ahead of time for such a phenomenal camera.

Tom Lowe
05-09-2007, 07:56 PM
If we shoot in 4K Redcode RAW, is it possible to crop the sensor to an aspect ratio of 2.40:1 (cinemascope) and achieve frame rates faster than 30p?

This is the 64 million dollar question. I agree that overcranking at 4K REDCODE RAW onboard will far and away be the most requested upgrade.

Thom Steinhoff
05-09-2007, 08:32 PM
This is the 64 million dollar question.

64 Million, huh? Okay "Not at this time"!!!!

Show me the money!!!!

Shawn Nelson
05-09-2007, 09:00 PM
I definitely agree, the people want overcranked Redcode RAW!!

C.H.Haskell
05-09-2007, 09:20 PM
I second this! RED has done the impossible, lets see 4k @ 60fps!

Wishful thinking? ;)

Stephen Gentle
05-09-2007, 11:56 PM
Sure, but Jim said "RGB sucks" and to shoot in REDCODE RAW :)

And I have to agree after all I have read.

But, for limited slow mo sequences, it might be just the ticket.

I doubt it sucks... It's probably just that REDCODE RAW is so much better!

Anyway, 2.40 slow mo sounds great (even if you could only go up to 40fps... Also, being able to shoot 4.5k 2.40 (less pixels than of 16:9 4K I think) would be great too.