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zijital
05-03-2012, 10:35 AM
Any one seen any mention about shooting at variable frame rates? This is all I've seen:


Frame Rates 23.98p, 24p, 25p, 29.97p, 30p

So I'm guessing nothing above 30fps, which rules out 60fps. But what about shooting 12fps or 18fps or...?

Andrew
05-03-2012, 12:59 PM
I don't think variable frame rates is an option yet. I hope they add it, even if it's an after launch firmware update. I think VFR is an important feature of a cinema camera. Under/over cranking have many great uses.

I hope to see 1-30fps variable.

The BMC is not the best timelapse camera, but I would definitely use 1fps here and there.

dunphy
05-09-2012, 10:57 AM
I read somewhere that the sensor couldn't read anything above 30fps. This was of course speculation in the article but is there any truth to that?

Meaning can a sensor be limited to how many fps it can offer. I'm hoping that this camera can be updated through firmware or before it ships to give it 60 fps capability.

mbeck
05-09-2012, 12:22 PM
We don't know what the sensor is. We think we have an idea, but we don't know for sure. Besides, it will most likely come down to the ASIC that BM chose for the camera that will limit frame rates. They could have put a faster ASIC in, but that would have made the camera cost more, and that was not BM's goal with this camera.

Andrew
05-09-2012, 12:37 PM
Sorry Dunphy, but the chances of seeing 60p in this camera are extremely small. Some of us are hoping they can squeeze in a bit more, like 36 or even 40fps, but that seems unlikely too.

Peter J. DeCrescenzo
05-09-2012, 01:18 PM
Any one seen any mention about shooting at variable frame rates? This is all I've seen: [BMCC specs] So I'm guessing nothing above 30fps, which rules out 60fps. But what about shooting 12fps or 18fps or...?

See:
http://www.bmcuser.com/showthread.php?172-Specs-on-its-Shutter&

Tzedekh
05-09-2012, 01:40 PM
We don't know what the sensor is. We think we have an idea, but we don't know for sure. Besides, it will most likely come down to the ASIC that BM chose for the camera that will limit frame rates. They could have put a faster ASIC in, but that would have made the camera cost more, and that was not BM's goal with this camera.
The overall throughput of the camera also determines what frame rates are possible. Use of uncompressed raw places a heavy burden on the camera. At 5 MB/frame and 30 fps the BMC has to move 150 MBps, nearly three times the maximum data rate of the Red Scarlet-X.

Tzedekh
05-09-2012, 02:10 PM
Sorry Dunphy, but the chances of seeing 60p in this camera are extremely small. Some of us are hoping they can squeeze in a bit more, like 36 or even 40fps, but that seems unlikely too.
Based on what exactly? BMD has said nothing about which sensor they're using, whether new frame rates can be added, or anything else. All we know is that right now the current limit is 30 fps, but if the sensor is indeed the BAE/Fairchild CIS2051, it's not what's limiting the frame rates. It's capable of 100 fps at 2,560 x 2,160 and higher rates in various windowed modes.

mbeck
05-09-2012, 02:26 PM
The overall throughput of the camera also determines what frame rates are possible. Use of uncompressed raw places a heavy burden on the camera. At 5 MB/frame and 30 fps the BMC has to move 150 MBps, nearly three times the maximum data rate of the Red Scarlet-X.
True, but with a faster ASIC, you could do windowed or prores/DNxHD version with lower datarates. (or even compressed cinemaDNG)

Tzedekh
05-09-2012, 02:45 PM
True, but with a faster ASIC, you could do windowed or prores/DNxHD version with lower datarates. (or even compressed cinemaDNG)
We don't know anything about the processing capability of the camera. Do we even know that it's an ASIC and not an FPGA?

mbeck
05-09-2012, 02:47 PM
We don't know anything about the processing capability of the camera. Do we even know that it's an ASIC and not an FPGA?

Nope! It's all pure speculation at this point.

dunphy
05-09-2012, 02:57 PM
Thanks Andrew, and mbeck for the info. I'm hoping for whatever can be expanded on from 30fps. Either way, I've already pre-ordered and am pumped about the camera.

Andrew
05-09-2012, 03:54 PM
Based on what exactly? BMD has said nothing about which sensor they're using, whether new frame rates can be added, or anything else. All we know is that right now the current limit is 30 fps, but if the sensor is indeed the BAE/Fairchild CIS2051, it's not what's limiting the frame rates. It's capable of 100 fps at 2,560 x 2,160 and higher rates in various windowed modes.

My opinion is based simply on the fact that they have announced the specs of the camera and it is 30p max. Of course things could change before it ships (or possibly after) but I think we need to get real about what this camera is and not project our own dreams and wishes thinking BMD will just add it all in a simple firmware update.

I want fast frame rates just as much as most, but I stand by my opinion that the chances of the BMC getting 60p are extremely slim, and even 40fps I won't hold my breath for. I hope they give us the maximum frame rate the currently spec'd camera can handle be that 33, 36, 40, etc. but for all we know, 30p is the max the current hardware can handle.

Barry Green
05-09-2012, 09:22 PM
Was gonna type it, but Andrew already said it -- the published specifications call for 30fps. Do NOT count on it being any different than 30fps. Never buy something hoping that it'll be different than what it currently says it is, that way lies madness. The BMC is a max of 30fps, up until BlackMagic revises their published specifications.

Tzedekh
05-09-2012, 10:10 PM
But that wasn't my point. My point wasn't about wishful thinking. My point was that saying it's unlikely ever to do more than 30 fps is as groundless as saying it's likely to, because BMD hasn't published anything about how upgradeable the camera is or what its intentions are with the camera. Just because the current maximum is 30 fps doesn't necessarily mean anything other than that's the current maximum frame rate. You're right, one should never buy a camera hoping it will improve, especially in the way one wants it to. But that's not the same as saying it won't or can't.

Barry Green
05-10-2012, 04:50 PM
I didn't say it wouldn't, I said don't count on it. The only thing you can count on is the published specs.

thegregferris
05-10-2012, 04:59 PM
Agreed, I bought a D7000 on the assumption that Nikon would - down the line - update the firmware to give me more than 24fps at 1080p. They didn't, and every subsequent DSLR they released did. Totally my bad. Blackmagic will have given me a bunch of useful frame rates in a amazing camera and I'm grateful. If anything is added later (which they have done with most of their other products) is a bonus.