View Full Version : HD-SDI on compact flash?
gene1102
03-22-2008, 02:22 PM
http://www.convergent-design.com/
This looks promising for green screen work, are there any existing devices similar to this?
Brochure:
http://www.convergent-design.com/downloads/Flash%20XDR%20Brochure.pdf
Thanks,
gene
RCFisher
03-22-2008, 03:33 PM
If you are going to be doing greenscreen work why not use the AJA IO-HD, far less compression. Maybe uncompressed although ProRes may be just as good as uncompressed at ProRes HQ (220Mbs). The max that the convergence box will do is 100 long GOP or 160 interframe compression.
Cheers
Robert C. Fisher
Cinematography
Elton
03-22-2008, 03:49 PM
The point of this device is 'less cumbersome portability'. Don't you like the idea of being able to mount the recording device to your camera rig (look at the XL-H1 picture in the pdf) and not needing a capture technician on set or in the field?
It's practical in the same way a Firestore is but provides high quality compression options.
Robert M Wright
03-22-2008, 04:51 PM
The point of this device is 'less cumbersome portability'. Don't you like the idea of being able to mount the recording device to your camera rig (look at the XL-H1 picture in the pdf) and not needing a capture technician on set or in the field?
It's practical in the same way a Firestore is but provides high quality compression options.
It should be far lighter, use less power, and be more reliable than a Firestore (or any other hard drive recorder) also. Reliability of hard drives isn't exactly a gimmee when they aren't stationary while in operation. Despite the hefty price tag on it, it should be awfully inexpensive to manufacture, so prices should drop to next to nothing eventually (with some competition).
davide
03-23-2008, 01:46 PM
I believe cineform is making a recorder too. That's a tad pricey. It looks like my hope of attaching one of these to an hv20 to save money isn't going to come to fruition anytime soon. It's still cheaper just to get a prosumer cam.
davide
Robert M Wright
03-23-2008, 02:14 PM
Once designed, the cost of production for this type of device should be peanuts (assuming design is reasonably good), so eventually, in a competitive marketplace, the prices should drop like a rock.
RCFisher
03-23-2008, 03:26 PM
For the most part greenscreen work is very stationary, usually on a stage somewhere. Recording to drives via a laptop is a very good idea. I don't know where the idea that hard drives aren't reliable came from. Good quality drives last years, most of mine are older than 5 years and work everyday. In a production environment buy drives for a project then archive them, this assumes that you buy decent drives and not WD or Maxtors which have not lasted a year in my studio. Solid state media is a new direction but still isn't quite there yet.
I have been doing a long term project exclusively to P2 media for the last year but the archiving is still a problem so we archive to drives, 2 or more for long term. LTO tape is a possibility but expensive for the little guy. Some of these costs could be built into a long term project but requires trained manpower and commitment.
The cineform device looks really good but is still $2000 or so and recording to the cineform codec is so much better than HDV! What any of this requires is setting up a real life workflow, which is pretty similar to film in the big picture, and sticking to it with room for evolution. The big producers have been reinventing the wheel for every feature in the recent revolution but if we all just looked at the best practices for film production and retain those then it will be simpler in the long run. I have been looking at the convergent box and hope to have one soon for my project, MPEG2 4.2.2 @100Mbs now that's a decent datarate! It would be better if it were AVC Intra 100Mbs but not too shabby.
Also a bit of scuddlbutt, it looks like both SanDisk and Lexar will be offering SxS media in the not too distant future so the price could come down to decent levels, unlike P2 media which Panasonic jealously guards as a profit center. I know SanDisk had previously announced this but the hot news was Lexar, don't know if this is totally true but it sounds reasonable.
Cheers
Robert C. Fisher
Cinematographer / Photgrapher
Robert M Wright
03-23-2008, 09:19 PM
I don't know where the idea that hard drives aren't reliable came from. Good quality drives last years, most of mine are older than 5 years and work everyday.
They certainly build hard drives better than they used to. When I started building computers back in 87, head crashes were not exactly a rare event. Nowadays they are more reliable, by orders of magnitude.
Despite improvements in hard drive design, when a hard drive is in operation and is not stationary (like mounted on a camera, especially while shooting handheld), the odds of a head crash increase exponentially. Hard drives tend to stay healthy longer when they are sitting on something that doesn't move.
RCFisher
03-24-2008, 12:07 PM
People seem to forget that CF cards or solid state media in general is really new compared to hard drives. I have had far more data loss on CF cards in the last 5 years compared to hard drives. I have been using Digital still cameras since 1999 and have lost 8-10 CF cards worth of images but none in the last 2 years, the media is getting better. I have cards that have been through the wash and I still could recover the images from them, try that with a HD!
For studio work I think it's much faster to shoot to IO HD than to cards and download them, you still have to have someone to do that in a heated situation. Also you have fewer limitations on time with drives. If need be let her rip until the director gets what he needs from the scene. I don't condone this but it is a reality of today's production environment.
Robert M Wright
03-24-2008, 12:56 PM
There are big differences in quality of flash memory cards. The differences don't have anything to do with how they hold up to g-forces though. Right now I'm liking Transcend's line, for reasonably good performance at a nice price.
Robert M Wright
03-24-2008, 01:08 PM
For studio work I think it's much faster to shoot to IO HD than to cards and download them, you still have to have someone to do that in a heated situation. Also you have fewer limitations on time with drives. If need be let her rip until the director gets what he needs from the scene. I don't condone this but it is a reality of today's production environment.
Shooting in a studio, with a controlled environment, you can shoot quite safely to hard drives, if you set it up right. Best to have the hard drive separate from the camera in a stationary computer, which is being monitored so any dropout in the connection to camera can be spotted right away, and using a redundant RAID setup.