Even 10 times higher quantum efficiency shooting wide open on optical band targets would be physically impossible.
On top of that, 'Eliminates need for flash' is not a great title - most people who care about photography don't use flash much for direct illumination; very flat targets, indirect illumination, close-range zoomed in macro shots, and filling in a dark foreground are the exceptions. Cell phone shots look like cell phone shots in part 1) because they compensate for the tiny sensor with crappy LEDs, not even proper xenon bulbs, but mainly 2) because a 1/4" class sensor can only offer 1/3 the SNR of a cheap point & shoot 1/2.3" class sensor on a good day, for the same level of illumination: they need the flash to work, and so you get flash-based shots, which usually look horrible because of the distinctive way it lights the scene.
> ...most people who care about photography don't use flash much for direct illumination...
You might want to tell that to the nice people at Elinchrom, Profoto, Broncolor, Hensel, Bowens, Quantum, Paul C. Buff, and so on. Even on-camera flash for good wedding and event photography is normally the primary lighting indoors, since it can be controlled when the environmental (ambient) lighting can't be. "People who care about photography" master the light rather than letting it master them.
I was careful with my wording: 'direct illumination' - point xenon/LED directional flash at target, shoot, enjoy off-axis vignetting, severe distance limitations, extreme inverse square contrast effect, & sharp nearly-incident shadows. Reflectors ('umbrellas'), big diffusers, aiming the flash at the ceiling, all the hardware that the places you mentioned sell, are aimed at avoiding these effects while still controlling the light quality.
Amateur photographers don't know this. They use on-camera flash because their cameras force them to use flash to get a reasonable signal to noise ratio. For them (who will never even attempt to use specialized flash diffusers/reflectors), the best option for dynamic indoor & evening scenes is a bigger sensor camera, or if they want to get really fancy, aiming a speed flash at the ceiling.
Much of the lighting I do is very much direct lighting; softboxen and other play-it-safe modifiers have their place, but you couldn't emulate, say, Karsh's style with them. And the inverse-square law is your friend, not your enemy. Light is merely a tool to get the shadows in the right places.
We photograph about 20-30 weddings per year, and I can vouch for the control aspect. The color of light matters. A lot. Being able to consistently be at 5000K (the color temperature of most studio strobes) makes editing incredibly easier and quicker. Color casts from using primarily or exclusively ambient lighting can be hard to correct for and even virtually impossible in mixed lighting situations.
I was thinking more about the direction and size of the light source, actually (with contrast coming in third). I can always throw on a cut of CTS or CTO to get a near-match to the predominant ambient, and that, too, gives me a known colour temperature so RAW processor presets (or batch applications of adjustments or stored camera profiles if I'm using, say, a Color Checker Passport) can work just fine. The flash makes the diffeerence between taking your subjects to where the light is "good" and making good light happen where your subject happens to be. (Completely killing ambient means losing the context, which may be a good thing or a bad thing.)
A more sensitive and efficient sensor may make portable continuous light sources more practical in the field (modulo photon shot noise — no sensor can make light a less probabalistic phenomenon), but it doesn't eliminate the need to make good pictures under sometimes unfavourable circumstances. And unlike the stereotypical landscape photographer, an event photographer can't just pack it up and come back later when the light is better.
> most people who care about photography don't use flash much for direct illumination
I used to be adamantly against flash too. Then I read some of The Strobist blog. Now I am only against bad use of flash, the type built into P&S cameras.
Warning, it is very well written and way too informative. I don't even own a DSLR, but I really want to get my own remote speedlight just for the occasions when I use my friends' nice cameras.
> Even 10 times higher quantum efficiency shooting wide open on optical band targets would be physically impossible.
Could you tell more about the limitations? I always felt current sensors are very insensitive and hoped that the sensitivity could be improved immensely. Even sensitivity such as cats eyes have would be awesome.
Once you start working with extremely sensitive sensors in very dim lighting conditions, you are basically counting the number of photons hitting each pixel. Quantum efficiency is a measure of the percentage of photons which are counted. A quick Google search turns up a paper measuring quantum efficiency of a CMOS sensor, with the sensor in question measured at 37% (meaning a 3x improvement is physically impossible):
If you want to see what that translates to, look at high-end cameras. Bigger cameras tend to be more sensitive because the pixels are larger, and the support circuitry takes up a lower percentage of the surface area, leaving more of the sensor's surface area for the actual sensor. The current generation of DSLRs can go up to ISO 25,600 (or higher, actually). Searching Flickr will show you a number of pictures in extreme low light, taken without a tripod, yielding better detail than I expect my eyes would be able to discern (note: humans, compared to most animals, have excellent night vision).
If you're willing to sacrifice resolution you can get even more sensitivity, which enables you to do crazy things like shoot video of the Milky Way or a moonlit landscape. An experimental Canon video sensor shows this off:
By comparison, film has quantum efficiency below 10%, at least according to Wikipedia. Photographers were quick to ditch film in the ISO 800+ range, and I rarely use film as fast as ISO 400 since digital is so much more sensitive.
Can you see how many light sources there are close to the beach in many of the shots? Watch the shape and size of the shadows that girl casts on the sand. Moonlight only? Not so much...
I think the GP's point was to call that claim into question. I'm sceptical about the 1000x improvement claim as well. CCD sensors manufactured for astrophotography achieve 60+% quantum efficiency.
I think the efficiency of these sensors is quite good, latest generation full frame camera sensor operate well at lower ligh t than you can see in, for example.
Fitting more of them into tiny arrays and maintaining exposed surface is more of a problem, and noise properties could be better.
At the end of the day though, there are limits to what can ever be achieved with tiny sensors like we currently see in most cel phones; you can pack things in more tightly but you can't avoid the optical physics.
From the article, it sounded like the improvement was more around better retention of photo electrons, rather than enhanced efficiency. That would mean potentially longer useful exposure times due to deeper wells.
Parent is not talking about the percentage of photons that are translated into charge, but about the amount of charge that can be held on a given area during exposure without saturating & spilling over to surrounding pixels. Deeper electron wells with the same amount of readout noise would increase the dynamic range of the image; I don't see how we can deduce that this was the stated benefit from the article though, or how that benefit could even be recognized given the early stage of the technology.
What does that even mean?
Even 10 times higher quantum efficiency shooting wide open on optical band targets would be physically impossible.
On top of that, 'Eliminates need for flash' is not a great title - most people who care about photography don't use flash much for direct illumination; very flat targets, indirect illumination, close-range zoomed in macro shots, and filling in a dark foreground are the exceptions. Cell phone shots look like cell phone shots in part 1) because they compensate for the tiny sensor with crappy LEDs, not even proper xenon bulbs, but mainly 2) because a 1/4" class sensor can only offer 1/3 the SNR of a cheap point & shoot 1/2.3" class sensor on a good day, for the same level of illumination: they need the flash to work, and so you get flash-based shots, which usually look horrible because of the distinctive way it lights the scene.