A-cam dII 'High Definition RAW Format Motion Picture Camera

New photos! Looking good:

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It does look good, indeed. I wonder where the thread to attach it to the tripod's head is located, and also how balanced the camera is going to be if you use 35mm lenses on it. I guess that weighing only 1.5 kilos, the camera would have a better balance with the lighter c-mount lenses.

Andreas
 
I'm concerned because I have tried fully uncompressed with solid state and although possible, it's very expensive in cost and time. Is there any pricing info on the media? The 80gb memory card can store:

15 minutes of 25p (about 88mb/sec)
or 6 minutesof 60p (about 220mb/sec)

So the user will need about 10 cards to get a usable 150minutes of 25p or 1 hour of 60p without offloading media to hard disk. That's 800gb of high speed memory. As an example, 64gb of generic Mtron SSD is 800euro, so this could prove expensive, especially with the custom memory module from the manufacturer. It more than doubles the cost of the camera with todays prices, and that's for memory that is slower than the one promised on this 80gb module.

The camera and deck use usb to do the transfers, which is 20 to 30mb/sec real speed depending on host. So the transfers will be about:

1/4 real time for 25p
1/8 real time for 60p

So we need about 1 hour for transfering 15minutes 25p or 6minutes 60p with a single deck. Multiple decks could be a solution, but USB could prove a limit to multiple use due to the interface design which uses lots of cpu and shares the bus in many implementations.

How much will a deck be?

This is similar to panasonic P2, but much slower in real time trasfer ratio due to smaller recording times, large rates and usb interface, so at least 5 cards are required to keep the camera recording at 25p and 10 cards to keep it recording at 60p, even when somebody on set is offloading material to a large hard drive.

The amount of data and the slow transfer speeds could also be a problem in playback, no direct real time playback will be possible from the card usb deck, because it is unplayable DNG and the usb speed is not enough either even if that was possible. Dailies are also hard to create. An hour will take many hours for transfer, without including the processing. If daylies of 1hour 60p are impossible due to processing/debayer and transfer speed issues, this is not a practical situation for actual feature production. If dailies of reasonable lenght are possible with a render farm, this is still a problem for a 7,000 euro camera because just like the gobs of solid state media required for recording and keeping the camera running, it adds to the cost.

Even though generic cards get cheeper every few months and this 80gb card could follow that trend, the user still has to invest on multiple cards that depreciate fast. This would not be a problem on a 200,000 euro camera but this is a 7,000 euro camera.
 
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Otis,

I found this in the FAQ on the Ikonoskop website:

"Q. How many minutes will it take to download footage from the card to the Computer?

A. The card reader will be released at the same time as the camera and will support USB 2.0 at roughly 40MB/second. So 25 fps footage will take roughly double the footage duration to transfer to the computer (15 minutes of 25 fps footage = approx. 30 minutes of transfer time to computer). That is why we recommend at least 3 memory cartridges to one camera."

Would you say that it is unrealistic 40MB/sec?
 
40mb/sec is not very probable but even 40mb/sec is very slow when the real time data rate is 90-120mb/sec. USB was not designed to transfer data very fast. Apple desktops are especially bad at it but the Intel motherboards I use are very bad also. Here is a benchmark from a reliable source using a triple interface enclosure and getting 17-18mb/sec on macs:

http://www.barefeats.com/usb2.html

And one from a Lacie hard disk getting 19mb/sec on mac and 30mb/sec on macbook pro:

http://www.barefeats.com/note04.html

I believe 30mb is an ideal case scenario. Especially with the mac desktop usb speed issues. 20-30mb is what a normal controller gets on a typical computer.
 
SATA is the only logical choice. Low cpu use, fast, dependable and it only adds a few euro to the cost.

There are other design decisions that are very strange, but since I'm head of a project in this market, I will not get into details:)
 
Does anybody have any idea on which kind of c-mount lenses will work on the a-cam?

I guess that, given the size of the sensor, it won't be necessary to use lenses which cover the Super16 frame. Older 16mm switar, schneider, angenieux and cine-nikkor should perform well. I also think that the more recent c-mount lenses made for the bolex reflex (which are corrected to function with the prism betwen the film gate and the lens) should not be right for the dII.
 
It depends:

http://www.bolexcollector.com/articles/07_03_21.html

Remember that the pixel size on this camera represents 90lp/mm which is extremely sharp for film lenses/film stock. I think the resolution is overkill for the sensor size but there is demand for 1080p on everything and many 16mm film photographers believe they are getting true 1080p from 16mm. I have seen 2k scans of 8mm also:)
 
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Otis,

what you are saying is that C-mount lenses - or some of them - might not be sharp enough for the sensor? So the only way to see if they work properly is to do some camera tests. What about machine vision lenses? I know that Schneider, among others, make some very expensive C-mount lenses.

Andreas
 
For cctv, the quality will vary. The typical 80 euro CCTV lenses are ok with the pixel sizes on the sensors I use (6.5um and 7.4um) especially a little stopped down (f2) and for 1" lens models (used in their best part). A cctv lens must be really good in order to work with this specific sensor because the pixel size is rather small.

The "megapixel primes" might not be enough for 1080p 2/3" (about 5um pixel size), especially wide open because they are designed for 1-1.5megapixel on 2/3" which is about 6.5um pixel size or 75lp/mm. Anything marketed as a "5 megapixel" machine vision lens will be fine with this camera.

From personal experience with film primes, including the Optar series, these primes are similar to good cctv lenses (100 euro something) at equivalent aperture in terms of sharpness and the most expensive primes can reach megapixel lens performance in some apertures.

I think most film lenses are designed with 50lp/mm in mind. Just a guess.

Lets not forget that 16mm is not considered acceptable as HD by many tv stations. This is due to film MTF, but cine lenses are desgned for film, so don't expect miracles in cheaper or older models, especially zooms. These could even appear soft on 16mm film.

On the other hand, a little lens softness will not kill a closeup, it could even work to your advantage.

16mm users will expect their lenses to behave the same, which will be true, the result will be sharper than 16mm film in any case, the lens character will be there, so I don't think anyone will actually complain about softness. It's not the camera's fault.

The silicon imaging camera has a similar pixel size, so perhaps the users could recommend lenses for this camera.

In my project I will test as many lenses as possible, even the most affordable cine and cctv ones and present the results for sharpness at all apertures and bokeh. You can't expect the client to experiment at his own cost and rely on rumours. The first sampes I shot used a very cheap cctv lens just to show you can do stuff without spending much on lenses. A 12mm gives you a normal prime on 2/3" and you can probably shoot a masterpiece with a single manual prime:)
 
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