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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Reason for 2 CF cards?

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Martin Koch

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Another dumb question. I first thought the two CF cards in Scarlet might be used in some sort of a RAID configuration to allow for 100 MB/s write speed but then after looking at http://en.wikipedia.org/wiki/CompactFlash I saw that CF cards already support 133 MB/s data transfer. If this is correct what's the reason for the second card? Convenience? Backup possibility?
 
When the first card is full recording should automatically switch tp the second one allowing the first one to be removed. It can then be replaced by another one and the first one backed up to disc etc. so your recording is not interrupted.
Steve
 
I would say still speed. 133MB is probably burst and can't sustain that rate.

Do we know if RED is using CF 3.0 or CF 4.0?
 
Well since Ted said the Scarlet was good for weddings I can see two cards coming in handy. Sometimes during wedding you need an hour or two of straight recording time in long ceremonies or during busy receptions. So if one card fills up and it automatically carries over to the next like the HVX's P2 cards than you can throw in a 3rd CF card and ensure you're going to have uninterrupted recording for a long time.
 
jimhare said:
I would say still speed. 133MB is probably burst and can't sustain that rate.

Do we know if RED is using CF 3.0 or CF 4.0?
Click to expand...

4.0 is what the RED CF cards fall under. CF 4.0 was not so much a revision as a change of direction for the CF companies because the big names were putting out UDMA cards and the little guys wanted to get it in on that game without making their own designs which is why we have the plethora of sub-par UDMA cards at the moment.
 
Martin Koch said:
Another dumb question. I first thought the two CF cards in Scarlet might be used in some sort of a RAID configuration to allow for 100 MB/s write speed but then after looking at http://en.wikipedia.org/wiki/CompactFlash I saw that CF cards already support 133 MB/s data transfer. If this is correct what's the reason for the second card? Convenience? Backup possibility?
Click to expand...

Guys - be very careful not to mistake 133x with 133 MB/s - it is not the same thing!

Speed is often given as a multiplier, such as 4x, 24x, 40x, 80x and 133x. Usually 1x is defined as a write speed of 150 kB/s, that's 150 kilobyes of data per second. An 133x card should be able to write at a speed of 20 MB/s, an 80x at 12 MB/s, a 40x at 6 MB/s and a 20x at 3 MB/s.

As far as I know RED CF's are based on the new UDMA type CF cards that are rated at 300x - this should result in about 44 MB/s. I could imagine RED having them "specsed out" to manage 50 MB/s (resulting in app. 341x) in which case the two slots will be used as RAID-0 allowing the two-card setup to capture 100 MB/s...

Any of RED Samurais :shiftyph34r: are free to correct me if I'm wrong...
 
Impagliazzo said:
So Peter, is it really 100 MB/s? Looks fairly high for Scarlet.

Isn't it 100 Mb/s (12,5 MB)?
Click to expand...

Nope - it is 100 MB/s (MegabYtes), i.e. 800 Mb/s...
I don't see reason for it to be "fairly high". Just consider that D1 (standard definition uncompressed) tape recorders had to pull 20+ MB/s trick onto a tape! How long ago was that?
 
Even a RAID stripe across two cards won't be able to reach those speeds. Perhaps the EPIC and Scarlet are being designed with CFast in mind (where higher speeds are possible).

Also, the problem with two independent CF cards in a RAID set is that the chance of the set becoming broken. It's vital in a RAID array that the elements (drives) of that array stay together - if you were to shoot the two cards together as a RAID set, then they need to remain together to be downloaded (which presents a problem physically).
 
Sycophant said:
Even a RAID stripe across two cards won't be able to reach those speeds. Perhaps the EPIC and Scarlet are being designed with CFast in mind (where higher speeds are possible).

Also, the problem with two independent CF cards in a RAID set is that the chance of the set becoming broken. It's vital in a RAID array that the elements (drives) of that array stay together - if you were to shoot the two cards together as a RAID set, then they need to remain together to be downloaded (which presents a problem physically).
Click to expand...

And that's exactly what makes me believe that this 100MB/s is in fact 100Mb/s.

Did RED officially announce the speeds or is everything plain speculation based on the NAB PDF?

Anyway imagine recording images on a Scarlet with data rates higher than the RED One with only 8GB cards. People will be swapping cards like crazy.
 
Wouldn't it be more logical to have a small 2.5" external USB drive enclosure connected to the Scarlet camera via USB (and the camera plugged into a power source) to do long shoots rather than replacing CF hards (which the act of replacement may cause unwanted camera shake?)...

I picked up a 250Gb 2.5" pretty cheap recently.... 250Gb is a lot of space for recording video....
 
There is a reason for Scarlet to have FW (FireWire) 800, as it allows for transfer rates up to 100 MB/s - coincidence?

Gunleik is right about USB, not only it is not fast enough, but USB requires high computer "overhead" further reducing it's maximum transfer rate...

Impagliazzo, keep in ming that people rarely shoot high FPS, 90% of the time You would shoot 24, unless You specialize in SLOWMO...

And one last time - IT IS 100 MB/s (up to), not Mb/s...

I do however agree with Sycophant that using RAID-0 will present "few" logistical issues, but it is doable and two beefed-up CF cards will handle 100 MB/s... Especially by the time Scarlet is out. Maybe even single card will handle it with the current rate of evolution.

If You follow the introduction of new CF cards we could expect by EARLY 2009 to have a 64 GB UDMA CF cards that could handle way over 100 MB/s for bellow $ 200,- USD... Now that is something to look forward to...!!!
 
$200 CF cards won't fly if one of the target audiences is "soccer mom's" and if two are needed for each 15 minutes or so of video, must be kept together, etc. I know the 24p guys are here for transfer to film, but many of us prosumers (what a stupid term, I'm an amateur but serious hobbyiest) will never go to film and 30p or even better, 60p, is what we would like to use.

The Scarlet cries out for an external box to take that FW800 (or one of the other specified digital outputs) and turn it into a file system for a FW800 7200rpm drive and create ProRes422 files (for true HD of 1920x1080p60) and Final Cut Pro, or some other format which Firewire can handle which various editing suites used by vieographers who want a $3000 camera also use (FCP, Vegas, Adobe Premier, etc.).

Eddie O
 
edoates said:
$200 CF cards won't fly if one of the target audiences is "soccer mom's" and if two are needed for each 15 minutes or so of video, must be kept together, etc. I know the 24p guys are here for transfer to film, but many of us prosumers (what a stupid term, I'm an amateur but serious hobbyiest) will never go to film and 30p or even better, 60p, is what we would like to use.

The Scarlet cries out for an external box to take that FW800 (or one of the other specified digital outputs) and turn it into a file system for a FW800 7200rpm drive and create ProRes422 files (for true HD of 1920x1080p60) and Final Cut Pro, or some other format which Firewire can handle which various editing suites used by vieographers who want a $3000 camera also use (FCP, Vegas, Adobe Premier, etc.).

Eddie O
Click to expand...

The only problem I can think of with 1080p60 is:

Where can I play it? It's not part of Bluray spec.
Online video services like Vimeo won't play it either.

The only option would be someone actually downloading the original file and watching it. Would it be practical?

I'm not saying 1080p60 is bad, I just don't know how to bring it to people.

If I'm saying something wrong or there are other forms to make people actually watch 60p, please let me know.
 
Sycophant said:
Even a RAID stripe across two cards won't be able to reach those speeds. Perhaps the EPIC and Scarlet are being designed with CFast in mind (where higher speeds are possible).

Also, the problem with two independent CF cards in a RAID set is that the chance of the set becoming broken. It's vital in a RAID array that the elements (drives) of that array stay together - if you were to shoot the two cards together as a RAID set, then they need to remain together to be downloaded (which presents a problem physically).
Click to expand...

And it is specifically mentioned in one of the NAB interviews that the 2 CF's are for live swapping, not RAID. But it could change... And anyway todays CF's is useless in Scarlet on full speed - so they factor in the improvments for early 2009 in the high-end CF cards. This is normal design politics and it makes sense to base Scarlet on the technology available on release and not on year and a half old tech.
MHO.
 
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