Bigger Chips and Smaller Systems

So, what is in the coolness catalogue now. The two that everyone is talking about is the __________ and the ________, both introduced last fall and now released. Those who have to buy to fulfill a current project will do so. Those who can wait will do that, since the Red Scarlet is supposed to be just around the corner.

Red, as all good manufacturers should do, isn’t saying when the unit will be ready to ship. Jim Jennard wrote an interesting note to the RedUser Group giving an indication that there are possible delays due to the world-wide financial situation contributing to supplier problems. He says that smaller vendors get hit at times like these, not talking about themselves. 

These details remind us of certain basics in the physics of these devices and how the different components need to be matched with each other; lens, sensor, monitor, storage speed and access. They also remind us that it is never to early or late to review or learn the basics. Robert Clark has an excellent write-up on essentials at Digital Camera Sensor Performance Summary at his ClarkVision site. [Don’t slag off and miss the references at the end. There will be a test next weekend.]

Introduction [from ClarkVision site]:

Modern digital cameras contain electronic sensors that have predictable properties. Foremost among those properties is their relatively high Quantum Efficiency, or ability to absorb photons and generate electrons. Second is that the electronics are so good in most cameras, that noise is as low as 3 or 4 electrons and rarely worse than about 15 electrons from the sensor read amplifier. With the low noise and high Quantum Efficiency, along with the general properties of how the sensors collect the electrons generated from photons, it is possible to make general predictions about camera performance. …

The ideal sensor absorbs every photon, each photon would generate an electron and every electron would be collected and counted to form the image, all done with no added noise. Would images from such a camera be perfect (no noise and infinite dynamic range)? NO! All measurements of light (photons) still have inherent noise, called photon noise. The dynamic range is not infinite, but would have a maximum of the number of photons collected. For example, if you collected 1,000 photons, the dynamic range would be 1000:1 or almost 10 photographic stops.

We’ll close here so you can go to the site and learn more.

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