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I've been watching the Apertus/Elphel project for some time now. I too wanted a larger sensor to allow a nice shallow DOF. However, the more research I do the more I realize it can still be achieved. The digital cameras that were used to shoot the Star Wars prequels were 2/3" and they achieved a very cinematic look. The C-mount means you can get lens that are capable of doing this at a fraction of the price.

Really, the only true advantage of a larger sensor is having potentially larger pixels. This allows each photosite to capture more light and thus work better in lower light conditions. Think of a bucket capturing water. The larger the bucket the more water you can get.

Now, right now nobody seems to be manufacturing a full frame sensor that does what you need and is cheap enough. Once they exist I'm sure the Elphel/Apertus team will start using them.

Here is another interesting camera project that seems to debunk many of the perceived size sensor limitations. It' called "Drama" and is designed to be a camera capable of uncompressed video. http://dvxuser.com/V6/showthread.php?t=219424

Actually, no, at the typical bitrates used, MJPEG quality is much lower. The old-fashioned DV camcorders recorded at 25Mb/s, in 720x480 (NTSC) standard definition... the DV format is just a video optimized and standardized version of MJPEG. Compare this to the ~8Mb/s used for video on DVDs -- essentially the same quality from MPEG-2, less than 1/3 the bitrate.

The K-x records 720/24p in MJPEG... they would really need 65-75Mb/s for the same quality video you get with a camcorder in SD. They're using SDHC cards, Class 6 or better...they don't specify their video bitrate... the K-7 uses the same encoder, and offers modes up to 45Mb/s or more, but they also enable a higher resolution on the K-7, their odd 1,536 x 1,024/30p mode. Still, less than half of what it ought to be. What you get with this camera will be substantially lower quality than a DSLR (like the Canon EOS 5D Mk II or EOS T2i) that offer AVC at similar bitrates. You'll get more general artifacting than with an AVC camcorder.

The one exception might be very fast motion... interframe compression hits a weak spot there, of course. But then again, if you're shooting sports or other fast moving subjects, you want 720/60p or 1080/60p... 24p is weak for high motion video. And it's compounded by the fact the K-x locks the shutter speed at 1/24th in video mode, which is just plain nuts. And of course, you still have the typical rolling shutter distortion (the "jello effect") of any CMOS sensor camera, and in particular, the K-x has a pretty pronounced version of this effect, even for a DSLR (which are generally worse than dedicated camcorders, presumably due to the larger sensors).

And as well, they're doing 24p here. Real 24p. The video standard is actually 23.976fps. Not that adjusting it is hard, but WTF? There's absolutely no good reason not to record video as real video.

Memory cards are getting cheaper, but the current 32GB is the most you'll get for SDHC... and there's no support for SDXC in this model, for the 64GB cards (out now, but pricey). As well, Class 6 cards at 32GB are still pretty pricey... class 4 is around $80 nowadays. Not a shooting problem, because there's an upper limit of something like 24minutes to any shoot... like most DSLRs, it stops when it hits the 4GB boundary of a FAT32 file, rather than starting another file like a camcorder would.

Pentax uses MJPEG on the K-x because it's a beginner's ("entry level") DSLR, and they don't want to pay for either the licensing or additional video DSP to encode H.264. The computational requirements for AVC are on the order of 100x more than for MJPEG... and obviously, any digital still camera already had the JPEG engine.

Anyway... I'd do serious homework before selecting this camera (or any DSLR) if video is a significant target for its use. There's a long video-oriented thread about the D-x here: http://dvxuser.com/V6/showthread.php?s=a2fcac7736ec18bb3b1b69883720a0d8&t=183691

A good descriptive article here - http://www.dvxuser.com/jason/CMOS-CCD/

begin with

That all depends on what type of plastic it is and how it is made. Perhaps you didn't know that before Du Pont received a patent on making nylon from synthetic polymers plastic was made from plants. The old Cellophane plastic wrap was made from plant cellulose. Kodak used to make film from cellulose. Today bioplastics are making a comeback. Despite the recession, their market is expanding.

Falcon

Look at the images here: http://www.dvxuser.com/V6/showthread.php?t=175113 and tell me the 5D2 looks better. The 5D2 images are ugly.

Have a look here:
http://www.dvxuser.com/V6/showthread.php?t=101169
This is a very interesting discussion I am currently having with indie film makers, on how to use the internet and video sharing sites to produce web TV series and make money out of the whole deal.

Take the DV format for example, DV tape holds roughly 5 minutes of NTSC video per gig if you look at it from a storage point of view. A 60 minute DV tape =~ 12 gigs.

Moving to a higher chip density will allow these cameras and the new generation of HD pro-sumer cameras to record directly to "disk", saving huge amounts of production and post-production time in terms of media management.

The Panasonic AG-HVX200 http://www.dvxuser.com/articles/HVX200/ records directly to their "P2" cards which are currently 2GB per card. Recording in HD100 mode eats up 1GB per minute. Only has slots for 4 P2 cards. Move up to 8GB per card or 16GB per card drastically expands on-camera capacity. This is a HUGE market.

That means you're taking a frame about every 15 seconds, were you to fill that up.

Ah, but the real target for flash cards this big is people that are out shooting 24, 30, 60 frames per second. With something like Panasonic's P2 system, the demand for really friggin' big flash cards is going to keep growing. When a relatively cheap camera is capable of recording 1GB/minute of high-def video, you start needing a lot of compact, fast storage.

That means you're taking a frame about every 15 seconds, were you to fill that up.

Ah, but the real target for flash cards this big is people that are out shooting 24, 30, 60 frames per second. With something like Panasonic's P2 system, the demand for really friggin' big flash cards is going to keep growing. When a relatively cheap camera is capable of recording 1GB/minute of high-def video, you start needing a lot of compact, fast storage.

A really good site I've been lurking on is dvxuser which is a collection of folks who are shooting on the 24p DVX100(a) Panasonic camera. Some of these folks have produced some very amazing footage.

There is a new forum on that board looking at the new 24p model of the Canon that was just announced.

Another thing to think about is the next gen of camera which is 'just around the corner' - the HDV standard. While it doesn't look to support the 24p the above cameras offer, 720p & 1080i on a mini-dv tape sure looks exciting.

There's always new gear though. The DVX and XL crowds have an almost religious zeal to their love of their kit so maybe start by looking at these two cameras if you can afford them - at least you then keep your options open. 'film look' as well as 'news report' settings depending on your vision.

Your link isn't working but i found a site with a review of a similar product. What do you think?