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Old May 29th, 2004, 10:28 AM   #61
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why? because when you pick this thing up it feels like a camera not a toy and I don't want to shoot with a toy. It's a great lens and lens mount and has lots of room inside for the HD board camera to fit...Why is this wrong? Would you have me build a square box to shoot clients big budget spots with??

The Bolex uses a beam splitter...can you send me a link so I can see how this works? 60% to the film and 40% to the viewfinder?
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Old May 30th, 2004, 12:09 AM   #62
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what is a good optical beamsplitter ? anyone know about them?
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Old May 30th, 2004, 09:12 AM   #63
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Obin,
Have a look here for the Bolex manual:
http://www.evergreen.edu/media/pdf/Bolex_Manual.pdf
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Old May 30th, 2004, 11:23 PM   #64
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awesome...bolex uses a 20/80 beamsplitter...i will look for that
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Old May 31st, 2004, 02:04 AM   #65
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I have seen simular suggestions in the static adaptor link. We allready have a light loss, and now we have even more, it makes more sense to use an external monitor (or the magnetic monitor flipping technique, external mirror depending on camera) and correct in post, as whenever you do these things you get optical compromises.

Now Steve wanted to discuss the issues in this thread that was to list just camera and camera mods, so how is it going Steve (when you get back from work tommorrow).

Thanks

Wayne.
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Old May 31st, 2004, 12:54 PM   #66
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Lens mount

Where would I find a lens mount for a custom-built camera? Is there a supplier for components like this?

If I'm going to use 35mm SLR lenses, I could just buy a non-working camera body from EBay ...
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Old June 1st, 2004, 04:26 AM   #67
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A Ballows lense system was one suggestion (or make your own rail pack) there are links to others in the 35mm adapter thread.
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Old June 1st, 2004, 04:10 PM   #68
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hi everyone

I saw this ultra mini pc at The Vision Show East. It may not suit our needs, but the size is perfect...

http://www.fase.co.jp/IEEE1394en/PC-CUBE/
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Old June 1st, 2004, 04:56 PM   #69
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It is a slick computer, no doubt about it. The big failing for these applications is the lack of a good RAID interface. Under "IDE interface" they list one CF slot. The same box with the chipset that supports serial ATA RAIDs off of the southbridge (ICH5R) would be great. That keeps the data off of the PCI bus, where most of the limitations show up. That would be the ticket to a low cost, fast system.
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Old June 1st, 2004, 05:23 PM   #70
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sent them an email asking about SATA on the system...will let everyone know what happens...Steve it has gigabit...whynot pipe into that network port and record direct to disk on the PC-cube? the hard disk inside is not fast enough?
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Old June 1st, 2004, 11:27 PM   #71
 
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Hey Wayne,

Is he talking about the Summix camera? One thing I was curious about is wheather or not FCP HD could actually use the stream coming from whatever camera is being talked about here. It was my assumption that "DVCPRO HD" was a specific standard that the FCP would identify and therefore could interface with, as opposed to a generic 960 X 720 stream. I figured a generic stream would not register the same and thus would not be compatible, or am I wrong? If I'm wrong, then you could also use the same system for the 10 bit 4:2:2 1080p, but if I'm right, well, then no. Am I correct in assuming it's a specific codec that must be used? What's the status of the summix camera anyway?

For that matter, I'm getting kind of lost in all these different alternatives. Maybe you could make a quick summary of all the solid possibilities for me? (I know, I ask so much, but I'm just a little filmmaker in a big, scary world).

Thanks!
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Old June 2nd, 2004, 08:15 AM   #72
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Laurence

As far as I know he was talking about the Sumix camera originally (I haven't read it lately). There are at least 2 cameras going in threads here (I think some individuals are also getting their own heads to make there own). If you look at the viper thread I address some of the alternatives, problem is it is in Sumix's hands and we don't really know what they are doing yet. One thing for certain they were going to sell a camera box, no comrpession, everything else has to be settled by the buyer. Maybe he knows something we don't, or he is talking about another camera.

I have personally said to Steve that maybe we should just settle for a compresed 400Mb/s steam (if available, simply giving up on higher than 720p RAW 4:4:4 streams. Maybe Firewire 800, or 1 Gigabit ethernet streams). I share your bewilderment.


Richard
Cute, I wonder how many people would confuse it with a power supply if I left it on a desk ;)

Here is one of the cases I was looking at:

http://www.eyo.com.au/details_G-3688BK.html

I also was thinking of using another cube case and using the drive bay to house the battery.

But case modders make their own (and guess what I want to do).

About the limits of transportable computer:

Steve N,

I have heard of software RAID, or Virtual Riad (VIA), but haven't had time to research them, how pratical are they for what we want to do with upto 4 drives (the consumer IDE limit).

About processing, you maybe able to get two future VIA processors at 2 Ghz running in parralell (but in main baords), at a lot cheaper and more portable, lower power cost than a twin Intel server soluton, would that be able to help the situation? Your site advocates Cameralink as an interface, but unless we have a cheap card for that, would a multiple link USB2.0/3.0, Firwire, or Ggabit Ethernet be a viable cheaper solution for users. There is talk of satuating the PCI bus, but many advanced internal PC bus architechtures go beyond that (I think VIA/s internal bus was 266MB then 1GB/s and I don't know where it went from there, and AGP, Intel's PCI-Express and AMDs greatly exceed this) so if these interfaces by pass the PCI bus it need not be a problem.

Thanks

Wayne.
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Old June 2nd, 2004, 08:33 AM   #73
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Here is a link with tests regarding a RAID O array with 4 SATA drives (they claim a 200M/s Read - Write sustainable speeds):
http://www.barefeats.com/hard35.html
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Old June 2nd, 2004, 08:44 AM   #74
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<<<-- why not pipe into that network port and record direct to disk on the PC-cube? the hard disk inside is not fast enough? -->>>

Yes, I think that's the basic problem. The SATA 150 standard will run at 150 MB/sec, but IIRC, most desktop drives won't handle above 50 MB/sec or so.

For uncompressed HD, we need between 80 and 120 MB/sec, depending on the bit depth and frame rate. We will also be limited by the sustained throughputs of Gigabit Ethernet (approx 115 MB/sec) and Firewire 800 (approx 80 MB/sec).

Valeriu's link shows that a relatively inexpensive 4-drive array can handle 184+ MB/sec on a sustained write, which should be plenty. (A 3-drive array might be enough.)
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Old June 2nd, 2004, 08:57 AM   #75
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Wayne,
There are two reasons why we are proponents of camera link at the high end (we do USB 2.0 at the low end and GigE for medium speed). First, honestly, most of our applications are industrial and camera link is *the* standard in non-cinema connectivity. Second, it is very fast and extendable. Base camera link has 3 8 bit channels which can be used as two 12 bits. 64 bit frame grabbers are available with dual base or full interfaces which doubles that. Data rates are high - the standard clock goes to 66MHz (at 24 bits) but the newer cards can do 85MHz. This means that you could run the AltaSens chip - 12 bit, dual tap 75MHz over to a single frame grabber.

Cost isn't so bad - our basic bundle with a camera (32 bit frame grabber, 2m cable, power supply and cable and some basic GUI software) is $500. The 64 bit/66MHz frame grabbers start at $1200 but will be dropping soon.

I've been talking to Xilinx (FPGA manufacturer with an HD-SDI demo board) about HD-SDI based on suggestions in this group but the spec maxes out at about 75MHz of data - you could do 1920x1080x30fps but not the 60fps the AltaSens is rated at. The design uses a Virtex II part - pretty expensive. This would be more cost than camera link. I'm not sure how 12 bit support works - the apps guy was talking 10 bit.

You can also get a cardbus camera link interface, but then you need to solve the disk recording rate if you go to a portable. There is also a PC/104+ frame grabber available to make a small card stack portable recorder.

GigE has its benefits - the best being 100m from camera to PC. Some of the latest chipsets from Intel put a gigabit interface off the southbridge - no bus bandwidth as you suggested. Still only 800Mbps continuous. Again not up to 2MPix x 12 bit x 60 fps, even with data packing. Not even 8 bit. Maybe 12 bit packed x 30fps but that will be close.
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