Sony's new A7s (12mp FF) why do you need a separate "recorder"to record HD and 4K video?

On Wed, 28 May 2014 21:55:01 -0400, Alan Browne
wrote:
: On 2014.05.28, 18:26 , Alfred Molon wrote:
: In article , Alan Browne
: says...
: Bring it down a notch to 4:2:2 (per the dpreview article).
:
: "The camera can read out its entire sensor fast enough to output 8-bit
: 4:2:2 4K video over HDMI at up to 30p, without the need for line
: skipping or pixel binning."
:
: Still - a lot of bandwidth - about 800 MB/s.
:
: Doesn't the camera use at least a bit of compression to bring down the
: data volume?
:
: I don't know. The above is a rough (from the linked calculator) about
: how much information is produced. Compression could probably cut that
: by about 20%, perhaps more.
:
: Another issue is how fast a disk drive can take a sustained write. RAID
: arrays are used to split the bandwidth (striping). Compression would
: help reduce that load as well.
:
: Redundancy would drive the disk number up (double or triple). RAID
: striping increases complexity (and processing at the storage end too, I
: guess).

It's difficult to generalize, because there are so many accepted RAID formats.
But the most efficient layout provides single-error-correcting redundancy with
a space penalty of about 16%. The penalty in processing speed is harder to
calculate, but there will surely be one.

Bob

On 2014.05.29, 10:44 , Whisky-dave wrote:

A certain look is that it, a look that they can't use an effect or
filter for is that it ? I just hope it's not the special grain/canvas
look they used on the last 4-5 seasons of Battlestar Galatica, it
looked really crap on upscalled DVD players.

That indicates poor mastering.

The wonderfully done "Fifth Element" looked great on DVD, and upscaled
beautifully on a Blu Ray player to Plasma.

When they released it on BR it looked like crap.

Sony recalled the BR disks and re-released it. That looks fantastic.

Digital cinema has a range ways to deal with high data rates. SSD,
RAID, etc. It's not really an issue other than cost. And Star Wars
have enough budget to shoot whatever format they want.

If it's not cost there must be another reason and I'm not convinced
by the 'look' idea.

You don't have to "see" it the DP has to believe it and choose it.

As a movie consumer you really have no choice in the matter other than
not buying tickets, disks or feeds.

--
I was born a 1%er - I'm just more equal than the rest.

On 2014.06.07, 10:22 , Robert Coe wrote:

: http://www.indiewire.com/article/10-reasons-why-filmmakers-should-shoot-film-according-to-kodak

The comical thing about that list is that half of the ten are more compelling
as reasons *not* to use film. The "trust" argument, as they state it, is
particularly absurd.

Kodak making ubiased claims, of course.

--
I was born a 1%er - I'm just more equal than the rest.

On 2014.05.29, 10:06 , Nick Fotis wrote:
On 29/05/2014 04:55, Alan Browne wrote:
On 2014.05.28, 18:26 , Alfred Molon wrote:
In article , Alan Browne
says...
Bring it down a notch to 4:2:2 (per the dpreview article).

"The camera can read out its entire sensor fast enough to output 8-bit
4:2:2 4K video over HDMI at up to 30p, without the need for line
skipping or pixel binning."

Still - a lot of bandwidth - about 800 MB/s.

Doesn't the camera use at least a bit of compression to bring down the
data volume?

I don't know. The above is a rough (from the linked calculator) about
how much information is produced. Compression could probably cut that by
about 20%, perhaps more.

Another issue is how fast a disk drive can take a sustained write. RAID
arrays are used to split the bandwidth (striping). Compression would
help reduce that load as well.

Another possibility would be to use SSD (solid state disks) instead of
RAID (the latest SSD are approaching the limits of SATA interface anyway)

Yes. Moreso those that are pure PCI w/o a SATA stage such as in the
Darth Vader Mac Pro.

"There’s flash storage, and then there’s next-generation PCIe-based
flash storage. We’re talking storage that’s up to 2.4 times faster than
the fastest SATA-based solid-state drive and up to 10 times faster than
a 7200-rpm SATA hard drive. "

https://www.apple.com/ca/mac-pro/


--
I was born a 1%er - I'm just more equal than the rest.

In article ,
says...

On Mon, 02 Jun 2014 08:03:46 +0200, Joe Kotroczo wrote:
: On 29/05/2014 16:44, Whisky-dave wrote:
: On Tuesday, 27 May 2014 19:44:02 UTC+1, Joe Kotroczo wrote:
: On 27/05/2014 14:44, Whisky-dave wrote:
:
: (...)
:
: I wonder if that's why they are recording the new star wars movie on film.
:
: well I doubt they'd be using a SD card but perhaps the data rate is just too high to be practical.
:
:
:
: No. They shoot on film to achieve a certain look.
:
: A certain look is that it, a look that they can't use an effect or filter for is that it ? I just hope it's not the special grain/canvas look they used on the last 4-5 seasons of Battlestar Galatica, it looked really crap on upscalled DVD players.
:
: Most of that was shot on Sony F900 and F950 camera in HDCAM.
:
: So: no.
:
: Digital cinema has a
: range ways to deal with high data rates. SSD, RAID, etc. It's not really
: an issue other than cost. And Star Wars have enough budget to shoot
: whatever format they want.
:
: If it's not cost there must be another reason and I'm not convinced by the 'look' idea.
:
: http://www.indiewire.com/article/10-reasons-why-filmmakers-should-shoot-film-according-to-kodak

The comical thing about that list is that half of the ten are more compelling
as reasons *not* to use film. The "trust" argument, as they state it, is
particularly absurd.

Actually that's the one that struck me as most valid. Digital makes it
easier for the Powers That Be to micromanage the production, whether
they know what they're doing or not.

Another comic touch is that the accompanying picture of the panel participants
is out of focus and needs a major white-balance correction. Perhaps the point
is that it wasn't shot on film.

Bob

On 2014.06.07, 11:07 , J. Clarke wrote:
In article ,
says...

On Mon, 02 Jun 2014 08:03:46 +0200, Joe Kotroczo wrote:

: http://www.indiewire.com/article/10-reasons-why-filmmakers-should-shoot-film-according-to-kodak

The comical thing about that list is that half of the ten are more compelling
as reasons *not* to use film. The "trust" argument, as they state it, is
particularly absurd.

Actually that's the one that struck me as most valid. Digital makes it
easier for the Powers That Be to micromanage the production, whether
they know what they're doing or not.

After shooting film is developed asap. Then scanned asap. So it's in
digital form very quickly.

"The Powers That Be" assign management to the producer, director and DP
and other senior production people. Micromanagement doesn't pay - even
when they do know what they are doing.

--
I was born a 1%er - I'm just more equal than the rest.