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

Nikon lenses focal length

Nikon lenses focal length

If I use my Nikon Still lenses with the IKONOSKOP-Cam - and the IMS system - will the focal length change?
 
Focal length never changes on any format, just the field of view. So a 50mm lens would be extremely wide on a large format camera but a 50mm lens on a small format camera would be extremely telephoto.

On a 2/3" sensor like the d2, a 50mm lens would have something like the FOV of a 125mm lens on a s35mm format camera- but the focal length actually never changes.
 
I got it, thank you Hunter.
When the FOV changes - does the DOF also change - or is it only like a cropped picture?
 
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It is very simple to predict results. You can calculate the crop factor of a sensor by deviding image widths. For this sensor it is 36mm/10.6mm=3.4 compared to 35mm full frame still photography. This has an effect on FOV and DOF but light gathering stays the same. Another issue that might affect results is the better geometry and lower aberations of the center part of the lens that is used on this camera and the pixel size that might affect effective resolution. On this camera (5.5um) it is similar to a multimegapixel still camera, so no real problem there. If the lens is sharp on a 12megapixel SLR at 1:1, it will probably be sharp on this camera.

An example for predicting the results you will get. A 50mm f1.4 will give you results identical to 50mm*3.4=170mm for geometry (field of view) and f1.4*3.4=f4.76 for focus (depth of field).

Another example, for 200mm f8 identical results on full frame still photography, this camera will require a 200mm/3.4=59mm focal lenght and an aperture of f8/3.4=f2.35.

This calculation applies to all sensors. For a 4:3 SD 1/3" camcorder the crop factor is 36mm/4.8mm=7.5 so for a 50mm normal field of view and geometry you will need a 50mm/7.5=6.6mm lens and the typical f1.6 aperture of these camcorders has an equivalent 35mm full frame still aperture of f1.6*7.5=f12 which explains the deep dof look.
 
Bertholt4 said:
I got it, thank you Hunter.
When the FOV changes - does the DOF also change - or is it only like a cropped picture?
Click to expand...

Btw, a cropped picture does not have different DOF (although it has a different look at it due to magnification). But once you change focal lenght to achieve what you actually had in mind (a 50mm FOV), your DOF will be different because you are using a wide angle lens. The calculation on the post above is correct because the only things important to the result of optical imaging is the combination of field of view in degrees and actual absolute size of the aperture in mm. It doesn't matter if the image is projected close (small focal lenght) to a small sensor or far (large focal lenght) to a large sensor. That is simply a magnification similar to projection to different screen sizes in a theater.
 
OK, Thanks Otis.
So, the 9mm lens which comes with the cam has a fov like a a 30,6 mm (maybe like a 28mm) full frame lens?
 
Yes, the 9mm f1.5 will be a 30.6mm equivalent with a DOF of f5.1 in full frame, so it will have a little bit of extra perspective for general use.

A practical normal on a 2/3" or 16mm sized sensor is a 12mm lens, but think of the 9mm as a lens that will give you a normal in a 4:3 center crop. This way you get a normal with room on the side versus a normal frame of view horizontally with a vertical look that looks cropped. The same applies to 2.4:1 shooting. You need to go a lot wider for a normal vertical field of view look.
 
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I wonder how they will ship so soon when three major Kodak ccd integrators (=old customers with lots of sensor orders in the past years) will not be able to get sensors until late december or later and promise shipping dates from January to June. Some of these manufacturers sell 1000s of cameras, have their own assembly line in-house and were already using and integrating Kodak CCDs for years. When you do have 1000 sensors in hand, it still takes a few weeks to have them integrated into a production level camera.

EDIT: I just read this on the forum and it sounds reasonable: "People ordering today are looking at April 2009 as earliest for delivery."
 
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6 months is not bad. These things take time. But they should present footage online at some point. A very early prototype or even a sensor board can do that. They should also finalize the specifications. From their answers they are still deciding on things like where thread mounts will be and what type and what's on the menus, audio, pc connectivity (sata or usb), workfow and things like that. We have seen the body of the camera in photographs but sometimes the discussion reminds me of a concept and not a product. Perhaps they are feeding the project from preorder money and they are expecting to get a reasonable amount of preorders, 800 or so to start production of boards, order a sensor batch etc.
 
Daniel Jonsater writes in the Ikonoskop forum that they will reveal their price policy next week, by then I guess/hope we will see some footage too.
BTW I saw some stuff at IBC and was blown away. This will imho become the perfect indy-cam.

Peter
 
In fact, if im not wrong almost more than a month ago they said footage was coming, but never apeared. I begining to think that they have advertised a camera that was not that completed in a technical perspective. As otis says even on a raw motherboard they can shoot and show some footage. Why so much time and only showing it on some places.???
 
A camera is hard to design. The SI camera took a while and it uses a normal off the shelf pc motherboard common in 3u racks, a normal off the shelf industrial pointing device, regular external tft monitor using normal pc connectors etc. I started my project in october 2007 and had it working by December 2007 and it still need a few months to get to production stage today. When you are designing a closed system, you obviously have more problems. You can't really order logic, media, components, etc and get them in a few days and this translates not only to added delays for inferior/simpler/older hardware technology but also increased cost you have to pass to the consumer. The problem of closed systems is that you are paying too much time and money for things that do not actually perform better. In the embedded application market, everybody is switching to embedded windows xp because processors are now efficient enough and system and software design for a few hundred units is more cost effective. If you are building 200,000 units using the same architecture within years, it does makes sense to go for a closed system and this is what large manufacturers do. In order to do this though, they lock specs, monitoring, sensor, media and even optics.

The a-cam dII as an example uses 640x480 monitoring. This means you only see one pixel for every 9 pixels and your 1:1 zoom options is too close to have any sense of what the frame contains (1/9 area view). If you want something with more detail that can mount of camera, it's not very cost efective and it removes the size/weight advantages. Closed system are like that. Red on the other hand do give you a nice 1024x600 monitor which is not exactly common in the video world and Si-2K gives you 800x600. 640x480 to 1024x600 does not sound like much, but on a 16:9 frame, it's 640x360 vs 1024x576 which is a HUGE difference (230kpixels vs 590kpixels). RED or SI or my design can integrate a new technology really fast. The typical camcorder will still be coming with low res (640x480 max) monitoring even 2 years from now.

To cut a long story short, delays are to expected in closed systems and any new product no matter how many resources are available.
 
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Thanx for your inputs Otis! It's very interesting reading. Keep on.

In this perspective how you compare new Red army of cameras and their Lego system? I think they hit the nail on its head and with expected mass production of some pieces we can get better prices on LCD, EVF, small lenses and other accesories. But we are still in stadium of CAD mockups and some raw prototypes.
 
I believe the 35mm film production equivalent (like the Red system) is not the answer to low cost feature film production. It's a high end film production approach designed to serve low end video production needs. A-cam is a lot more interesting and they are a competitor that I would like to think of as a partner since we are interested in producing different tools that can coexist beautifully on the market by completing each other. We both design to solve problems of existing systems by removing the limitations, not making an entirely new product category with lots of accessories and addons. That would make a good product but not a very good filmmaking solution IMHO. In marketing terms it would be a market leader approach coming from a market challenger. It doesn't make much sense.

Engineers focused on production management learn to think simply. What's wrong with a prosumer camcorder? What does the filmmaker need? Make a list and solve the issues one by one by designing something new or integrating an existing part. Simple as that.

When you are designing a consumer product you think in different terms. It's more like: What would the user buy? What need could I create? How can I make the user less satisfied with the product he is using? How can I create the basic acquisition need of goods that forces a purchase? How can I make the customer/user feel special about his purchase or even him/herself as a person? What would the feel of the product be? How can I upscale entry level needs? How can I take the branding to new levels without even providing something new? How can I get followers that do not even use my products? How can I take an entry level camcorder user and convince him/her he/she needs a 30,000 euro camera system? How I can differentiate? How can I sell more accessories? What is the toy/plaything factor? How can I plan to make a product obsolete within a year and force constant upgrades?

Anyway, that's what I'm trying to stay away from. I don't want a product like that. The last thing a low budget filmmaker needs is consumerism and psychological marketing. I have met quite a few, they don't need 40,000 euro setups that will actually inhibit their creativity or add new problems with their workflow or software issues or whatnot. So I'm focusing to what counts for me, the solution and how good it is in the actual feature film production situation.
 
I agree there is a vaccuum in the marketplace for a portable low-budget indie cam. It actually doesn't sound like Scarlet fills this vaccum--not for me anyhow. And I've been following the Ikonoskop with high hopes.

Ultimately, I just want a lightweight camera with cinematic DOF (no more adapters, thank you). The new DSLR's would be perfect if only they had fewer image issues and shot 24p. I just need something between the D90 and a Scarlet.
 
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