Here are a few thoughts i have on building our own video camera:
Basis would be a Canon 1100d/ T3.
Why a cheap (shitty) 1100d ? Well it has a 12 Mp APS-C sized sensor so there would much less noise at high iso than on a 7D/550D/60D.
We could skip the cameras built in Flash, Photo mode wheel, viewfinder, mirror and the shutter.
We could geht our own case cnc milled for this camera. Perhaps an aluminium case like the RED Scarlet.
We could also integrate an Mic input and skip the internal one.
Simon
Well I'm trying to do the same thing except for 600D. Its kinda 5dIII jr and the sensor is bigger. Maybe like 1/4 of the way there.
No need to rip the case apart. Need something like beactek/juicedlink for audio. Would love to get CF working somehow... the code is there, wish the pins were or there was a way to translate over HDMI, etc.
Ok cool but the 600d has an 18mp APS-C Sensor like the 7D/550D/60D anso so on ... so i wanted the 1100d.
I just thought it would be cool to have a custim made very strong case. and without all the stuff i mentioned before it wold be much more Weather/ Dust proof i think.
The noise performance of the 1100D isn't really stellar.....
The 600D is better in any possible way (no moire? check, Mic input? check, decentBetter LCD screen for ML stuff? Check)
Hm but then we cold also use a (cheaper) 550d right ?
Nope, no files over 4GB.
I don't see how you can use a canon camera. There no documentation on the sensor or the processor. I have been working on my own private project for a year now, it's based on this flow chart http://www.ti.com/solution/digital_video_camera_dvc I'm using a 1/2.3 sensor for testing. I want to get a Cmosis sensor http://www.cmosis.com/products/standard_products but I ask them for the specs and prices but they are asking me for the company I work for. I told them is for a private project and I never heard for them. Building your own camera is not simple. It's a great learning experience even if you fail.
There are already projects on kickstarter doing this.
You don't have to start from scratch, just get canon up to snuff or reasonably so. They did the hard work, i.e physical construction. People used to put up worse than where the HW is at right now. Building from scratch will give better results but nothing that will work for large amounts of people.
Good luck with getting an hardware vendor to sell this kind of stuff to you. Just think of the number of patents and agreements involved in a "simple" image sensor design ::)
China vendors might actually do it, especially the shadier ones. But then docs and support is nil.
http://www.kickstarter.com/projects/joedp/the-digital-bolex-the-1st-affordable-digital-cinem
But no reason why 5DIII/600D can't get close to this quality. 5dIII especially close to pulling off raw with CF speeds.
I saw this Project too.
But the sensor size is fairly small and there are only sensitiyity modes of iso 100, 200 and 400 availible.
I dont understand the point we discussed before, that the 1100ds noise performance is worse than other cameras ?
Whats the reason for this? i mean the 600d has 50% more pixels at the same sensor size. So each pixel on the sensor can be 50% biger and pick up 50% more light.
QuoteI saw this Project too.
BMCC also does what they want already at similar price and EF lenses :)
You can use the 1100D, most of the stuff is similar... but you get a smaller LCD and no crop mode and no audio input. Plus you'll have to do more DE-crippling in the firmware.
Probably all of these cameras will work to some extent, the sensors aren't really the problem. Noise is passable up to iso 1250. I get better performance on 600D than 400D in terms of that so I think smaller/larger sensor won't make a difference. Just limited by memory size, write speed and canon software.
What makes a cinema camera? At least 4:2:2 color, not so compressed video and somewhere around 2k resolution. Also good audio support. We're like 1/2 way there. The 30 min limit seems hard coded somewhere but most takes are way under that.
Quotemirror and the shutter
Mirror already goes up and shutter stays open.
Unless you're really into doing the HW part, I'd look at the software and try to fix it. You'll have to do it anyway for the mods and then some.
Quote from: 1% on October 06, 2012, 09:26:33 PM
China vendors might actually do it, especially the shadier ones. But then docs and support is nil.
http://www.kickstarter.com/projects/joedp/the-digital-bolex-the-1st-affordable-digital-cinem
But no reason why 5DIII/600D can't get close to this quality. 5dIII especially close to pulling off raw with CF speeds.
The digital bolex is just a modded prosilica gx2300. There's documentation on the sensor and processor. There no documentation on anything canon made. It's hard enough with the right documentation. And to build a camera you have to built it around your sensor and processor needs. Look into http://www.apertus.org/ if you want a open source camera.
That's actually what I was looking for but found the other guys first. Still seems like nobody is pulling it off for <$5k. Far cry from $500 600D.
If you use exFAT format you can go over 4GB file limit
Well, if you have 300.000$ to spare send them my way ::)
just wanted to throw a link in here: http://apertus.org/ - what do you think of this project?
Wow very interesting ! But 10000 $ is still way too much for a student like me.
Currently I`m using a 550d/T2i with a Sigma 30mm 1.4 and a Sigma 70-200 2.8 with magic lantern and I´m very impressed with this configuration.
But couldnt we get 24 RAW frames a second in Picture burst mode if we would disable the mechanic and would use a electronic Shutter like in movie mode. If the RAW pictures would be taken in 1080P resulution the Bitrate would be much lower.
Not enough card speed to capture raw. We can probably get raw at like 10- 12fps or something. In movie mode its smaller than 1080p even when recording. Some hope for 5dIII and really fast CF cards.
If you were to really rip the camera apart 600D could possibly get CF. Its similar to 5dIII and has support for CF + SD in firmware... maybe on the boards too but that would take soldering and where to put the CF? It would have to dangle on the side somewhere after you micro-solder 32(?) pins. Canon may have had this setup in the lab but its not like they're talking.
Looking at main PCB.
http://images1.wikia.nocookie.net/__cb20110912105115/magiclantern/images/5/57/600D-PCB1.jpg
Are all connectors used? I see one that's unpopulated.
http://www.ebay.com/itm/CANON-EOS-5D-MEMORY-CARD-CF-PIN-SLOT-UNIT-NEW-AUTHENTIC-ORIGINAL-REPAIR-PART-OEM-/330674813612?pt=Digital_Camera_Accessories&hash=item4cfdc13aac
If a ribbon connector (or even unpopulated) is there but unused near SD that would probably be it.
The CF slot uses a 50 pins ribbon. I don't see any slots to fit one in there. They are definitely using a different PCB layout (as expected, the 5D is a bigger FF camera)
Would like to see 5DIII ribbon but nobody is selling spares yet.
Quote from: 1% on October 18, 2012, 04:49:56 PM
If a ribbon connector (or even unpopulated) is there but unused near SD that would probably be it.
Yes but i only see 16 free pins ?!
What about Jpeg2000 Compression in Movie mode ? The Redcode Raw is based on this compression method. Its 224mbit/s which is not too much for fast sd cards.
224 mbit is too much. The limit in the controller is 25MB/s. Most cards can barely keep up with 15-20 sustained. That's around 160.
With CF I think its a little higher and that 224 might be possible. SD sucks, wish they kept it CF. Then we'd be shooting at max quality all the time.
Right now PTP jpegs fit within the bandwidth but only ~720P
Yeah but 224mbit is the bitrate RED uses for 4K video. So recording at 1080p would roughly one fourh of this.
224/4=56mbit/s whis is 7 Mb/s so even SD cards could keep up with this.
Quote from: nanomad on October 06, 2012, 08:51:23 PM
Good luck with getting an hardware vendor to sell this kind of stuff to you. Just think of the number of patents and agreements involved in a "simple" image sensor design ::)
I'd say its more of a quantity issue. You're basically not worth dealing with for the chip manufacturers unless you're talking quantities in the hundreds of thousands or more.
What about physically overclocking the DIGIC 4 ? I mean by chaging the chrystal next to the processor to one with a higher value.
We could add a little cooler to the Processor. Maybe this would enable us to shoot higer fps in video mode.
Quote from: Simon on October 27, 2012, 11:00:52 PM
What about physically overclocking the DIGIC 4 ? I mean by chaging the chrystal next to the processor to one with a higher value.
We could add a little cooler to the Processor. Maybe this would enable us to shoot higer fps in video mode.
::)
G33ggo said the processor doesn't have much overclock room. There are a few versions, one is rigged for speed and the other is for something else (arm site). I think we have the slow proc. Changing the crystal is too much work, not worth opening the camera and might not work.
I've overclocked a bunch of ARM router + phone stuff and if you go past a point the proc just doesn't boot.
Overclocking the CPU could potentially screw up timings (I'm not so sure actually, but it could happen)
Who needs a full frame sensor when you can get a whole scanner ? ;)