Great explanation Don. Now lets see how many Forum Engineers rip into it.Ultimatly, there are only so many photons.
Lets use a pair of imaginary sensors to show the point with easy math. Both sensors are perfect, and both have a perfect A/D circuit to read them. Both sensors cover the same area, one is 10X10 pixels, the other one is 40X40 pixels.
Both sensors are mounted into a camera and are going to take the same picture of a white wall at the same exposure and aperture. Let's say 102,400 photons enter the lens and because our imaginary sensors are both perfect, we get 102,400 electrons. The 10X10 sensor has 100 photosites with 1024 electrons in each one, and this gives us 10 bits of colour depth. The 40x40 sensor has 1,600 photosights with 64 electrons in each one, and that gives us 6 bits of colour depth.
The 10X10 sensor has greater colour depth, but the 40X40 sensor has greater resolution.
However, you can bin the pixels of the 40X40 sensor to recreate the same image as the 10X10 sensor, and end up with the same lower res image at the same colour depth, but you can not go the other way around. The 40X40 image has more information than the 10X10 image. think of it like this, 10X10 X10 bits of depth is 1000 bits of information, while 40X40X6 bits of depth is 9,600 bits of information.
In the real world, it isn't so easy. A/Ds are not perfect, sensors do not have 100% quantum efficiency, and there is a seam on the edges of microlenses so some light is lost there, but it still comes to the same conclusion. Smaller pixels capture less individual cell info than larger pixels but because there are more of them, the overall amount of info for the entire image is greater.
---Do we have a new HF?
Thats because talking about resolution in terms like that is an entirely specious argument.Surprised no one has talked about the lenses that will be needed to fully realise this kind of resolution. Does this mean all new RF L lenses will be a step above second gen EF L lenses?
Another formula is the product of the transfer functions of each block in the system. The conclusion is the same: the total system resolution approaches the weakest link. Improving the strongest link will result in diminishing returns to the system, and improving the weakest link can result in the greatest returns to the system.Thats because talking about resolution in terms like that is an entirely specious argument.
Reposted yet again:-
System resolution can be broadly shorthanded down to this equation, it isn't perfect but pretty close.
tsr = 1/sqrt((1/lsr) ² + (1/ssr) ² )
Where tsr is total spatial resolution, lsr is lens spatial resolution, and ssr is sensor spatial resolution.
So if, for example, we have a sensor that can resolve 100 lppmm, and a lens that can resolve 100 lppmm we get this
1/sqrt((1/100) ² + (1/100) ² ) = tsr of 71 lppmm
Leave the same lens on, good or bad, and double the sensor resolution to 200 lppmm
1/sqrt((1/100) ² + (1/200) ² ) = tsr of 89 lppmm
You will notice that the system resolution, even in this simplified form, can never resolve 100% of the lowest performing portion of that system, so if a 24MP sensor is returning 80% of the potential of a lens then a 50MP sensor might return 90%, how useful that is in real life is a moot point, but it does illustrate that even the most modest lens will show increased resolution when put in front of a higher resolving sensor.
That's true, and I didn't mean it that way, sorry if my posting was mistakable. In general, the image information captured by a e.g. a 35mm sensor is always the same, given the same amount of light and comparable silicon technology, and given a minimum pixel size that fits to the size of the Airy discs caused by a certain aperture. For those not knowing what an Airy disc is: That's the area of a geometrical image point washed out by diffraction, and such a disc contains no useful image information. Now, starting with an aperture in which Airy discs and pixel pitches fit together, and closing it further, those Airy discs grow and overlap more and more pixels. So, now you lose gradually more and more image information captured by a single pixel - the image get's softer and softer on the pixel level. If you e.g. close to f = 14 for classic landscape photography to gain a big depth of field, you just get fat files from your 75 MP monster that include no more useful information than smaller files from a, say, 24 MP camera. Your just need more processor power and disc space for such huge files, and emit more carbon dioxide into earth's atmosphere.A higher resolution sensor will never perform worse than a lower resolution sensor due to diffraction or motion blur. Blur may stand out more when pixel peeping at 100% because the higher resolution file is enlarged more, but it's not actually any worse at the same view/print size.
Diffraction is also not a brick wall. "Diffraction Limited Aperture" is terrible terminology because it causes people to think of it as a brick wall.
Whoa! And I always think I tend to write too long posts, respect, HarryFilm . You should re-establish French style epic novel writing of the 19th century. Just polish a bit the dramaturgic composition of your posts..."...Harry, do I have the magical ability to summon you? It appears that way....."
YES! You do....I AM HERE....i am there....I AM EVERYWHERE YOU WANT TO BE !!!!
with the LATEST in Camera Industry Rumours......and I do wish to update you all on a previous one which I think is HOT TO TROT !!!!!!
WE SHALL SEE ....and..... YOU HEARD IT HERE FIRST !!!!!!
That's not completely true. 40X40X6 needs to transfer that much more bits of data (unless pixel binning is implemented directly between photocells), but how much extra information this extra data contains depends on how much information in the corresponding frequency range (5 to 20 cycles per sensor) actually reached the sensor.think of it like this, 10X10 X10 bits of depth is 1000 bits of information, while 40X40X6 bits of depth is 9,600 bits of information.
When you look at the "competition" and "wish" Canon made "one" like that ? Why?I'm not tracking the people you see as offenders, meaning I don't know who is complaining both ways. But it is so easy to just lose patience and call those who don't share enthusiasm a troll. From what I understand, a troll is somebody who, perversely, posts in a forum for the sole purpose of angering reasonable forum members.
But what I'm reading in this thread, for the most part, is understandable frustration, skepticism, and concern. You might not agree with such sentiments, but people spending thousands of dollars, sometimes unwisely in terms of their own budgets, get emotional, cynical, and even bitter. If they are posting simply to express their feelings (and I'm seeing quite the surge in newer members since the EOS R was released), are we to just call them all trolls--without even engaging first to find out what their actual issues might be with a Canon releasing a 75 MP before, say, a best in class 40-50 MP? (Maybe Canon has discovered the Holy Grail of sensor tech, who knows?)
Now if I tell you that it would be nice if Canon made a dSLR as good as the Nikon D850, would you call that trolling? I don't think it is. Yes, Canon makes calculated, clear-eyed business decisions that have kept it the leader, but, as a customer, I can't help look at the competition and think to myself, I wish Canon made one like that. So, while I support the development of higher resolution bodies and lenses for those seeking such specifications, I'd also like to see Canon addressing the desires of many other photographers who, like myself, aren't seeking more MP at this time.
Is it rude to say, "Hey, what about me? My photography desires deserve priority!" while in a thread about rumored gear a member doesn't find appealing? In a way, yes, I'll grant you that, dak723. But it's an open forum with relaxed rules about staying on topic, and people react with their first thought, little filtering. I don't think it is helpful to just classify such posts as trolling, because, one, they are not, and two, it doesn't help the thread, the person posting, or the general feeling of goodwill that CR manages to maintain better than many other sites.
Just my opinion!