wdross Loc: Castle Rock, Colorado

"Sweet spot" is a relative term. For many pros 20mp to 30mp will be enough for a two page magazine spread. 24mp would be adequate for such. For an 10' X 12' wall piece, where people are likely to get close up to it, 24mp will probably not be adequate. For photographers making these kinds of larger prints, they will have to spend the money for the camera to do so. So where are the pro markets these days? Magazine spreads, annual reports, 11X14 prints, etc. For many, they can even get by with a 4/3rds camera because of the sensor shape (normally requires less cropping for common sizes which tends to equalize the differences in pixels).

It just depends if they can improve the pixels of smaller sensors both in number/size and in quality. So much will depend on where the image market is going. Right now the biggest users of images are smartphones and tablets along with magazines. Where is the incentive to invest in larger sensor R&D? Where is the incentive to carry even bigger, heavier, and more costly cameras?

A recent industry consultant thinks both the market will get smaller and APS-C cameras, not full frame, will become the industry standard. This is why I feel APS-C and 4/3rds will end up eventually taking the majority of the future market even with the enormous amount of full frame equipment in existence. This will be only further propagated by increased mp and quality in the smaller sensors along with decreased size, weight, and cost in the bodies and the lenses. And it is mostly the lens weight that even allows Panasonic and Olympus to show up on the sales charts. The bigger, heavier, and more costly camera systems will have a very hard time drawing consumers away from their smartphones and tablets. And if the pro market needs increases in smaller size images and imaging, the market for view cameras, medium format, and full frame to meet such market requirements will get even smaller.

So as long as the DR of any size sensor can meet the market's minimal needs for prints and monitors, it will not be as important a factor for deciding which camera or format to purchase.

gwilliams6

Certainly APS-C size cameras have their necessary place in the market due to size ,weight and cost. I loved my APS-C size Sony A6500, it was great for travel. Still fullframe mirrorless cameras are dominating the mirrorless market in technology advances and sales. So what did Sony do, they came out with the A7C, a fullframe mirrorless camera, that was the size of an APS-C size camera and it has been a runaway sales success.

In my experience most fullframe mirrorless camera owners also have excellent smartphones with good cameras. So it is not an either-or situation here.

Whereas the compact mirrorless camera market has been decimated by the smartphone, smartphones are NOT the professional's choice over their fullframe cameras. With the amazing quality of smartphone cameras nowadays most shooters wont own all three fullframe, APS-C and smartphones for stills and video.

As excellent as APS-C and micro 4/3rd cameras are, cameras sales just are not trending to them over fullframe mirrorless cameras. Check the CIPA worldwide numbers. Those who love their APS-C and micro four thirds have excellent choices that satisfy their needs. For my personal and client work, fullframe is just better in resolution and low light, with less noise, and more preferable shallow depth of field.

Most shooters here will never see or need the differences, and that is fine. For many ,saving the costs, weight and size makes the decision easy. Maybe the real future is what Sony did, squeezing a excellent fullframe sensor into a nearly APS-C size body in their A7C.

The point I was making was in answering the notion that for better dynamic range, a 24mp sensor was the sweet spot. I own a 24mp Sony A9, a 61mp Sony A7RIV, and the video-centric A7SIII which is just 12mp, perfect for the one-to-one pixel readout for 4K, with multiple framerates. My 61mp A7RIV has even better dynamic range than my 24mp A9. Nowadays advances in sensor technology determines the dynamic range much more that sensor size. Cheers

User ID

Amen. Made my living with 8x10 and smaller films. With digital, my direct commercial grade replacements are as follows below. YMMV.

Formats:
4x5 and 8x10 sheet film, “$$ forget it”.
6x9 roll film = 50 and 80MP.
645 and 6x6 = 50MP.
135 = various small digital cameras.

Special Cameras:
Studio Monorail, “$$ forget it”.
“Field & View” = high MP + T/S lenses.
Circut and Pano = digital magic (>=)


======== off topic ========

One outlier is gorgeously grainy and halated, overcooked, severely filtered, monochrome IR film. No digital method is even vaguely similar.

Another outlier is “almost full toned” printing on Kodalith paper. No digital equal, but I can come sorta close.

Despite these two losses, digital has given more than it has taken away :-)

wdross Loc: Castle Rock, Colorado

Agreed. As for your "sweet spot" camera, it is definitely determined by your clientele. As you pointed out, many of us are not necessarily using our photography to earn our paycheck. Then it comes down to what shooting we are doing. I would give up my 4/3rds camera if I was always shooting in low light and/or always needed very shallow depths of field. 4/3rds will not cut it in those constant situations. One must take on the larger sizes, heavier weight, and more cost or fail to compete with others that are willing to do so. I personally am happy to see some of the larger formats come down in body size and their weight. But the other formats have a much harder time, though not totally impossible, reducing the size and weight of the format's lenses. For most pros, it is whatever camera (their tool) meets their needs without worrying about format. Like Bill at Burkphoto says he will use his 4/3rds for 95%+ of his work and rent when he needs a larger format. A lot of people who are not pros end up just buying by name brand rather than actually exploring their needs. Most people only need to look at their shooting subjects and their style's requirements for depth of field and ISO and then balance them against size, weight, and cost. But there are the times when recording fine art or other absolute accuracy renderings where dynamic range does become a part of the size, weight, and cost versus DOF and ISO equation. They tend to be the exception rather than the rule. So as new photographers enter the market, especially as enthusiasts and amateurs, they may look at things differently than a lot of photographers do now. I think this is why there will be a shift from full frame towards APS-C and 4/3rds. There will be enough dynamic range for their needs within those two formats.

Hanson

hjkarten Loc: San Diego, California

I bought a A7Riv about a year ago, and love it. I use it to shoot birds in the local marshes a few days a week. But I still have my A6500, and love its small size and ease of slipping into a jacket pocket. It is notably lighter than the A7R4, especially as I tend to load the A7R4 with a larger (and heavier) lens even when just using it with a walk-around lens. As a result, and with no intent to replace either camera with a new A7C, I played with an A7C for a short time in the local photo store. I realized instantly what has been so appealing about the A7R4 a vs. the 6500 for trying to photograph birds in flight. The A7R4 (as well as most of the other A7 series) have larger viewfinders. But even more attractive is that the viewfinder is in the same vertical plane as the lens itself. This makes it much easier for me to more quickly align a telephoto lens with a bird in flight. Do you have any hints for more rapid alignment of lens with a flying bird on the 6500? I found the A7C had the offset viewfinder, similar to that of the 6500, and was therefore less advantageous than the A7R4. I tried using the Olympus Red Dot sight. It works better on the A7R4 than on the 6500, because of the same alignment issue. I suspect that the A7C might have the same shortcoming. An additional appeal of the A7R4 is that it remains the only full frame Camera comparable in resolution within the cropped field to the 6500, and capable of providing approximately the same pixel density within the central image field. (the 6500 has 24 MP, and the A7R4 has 26 MP in the APS-C part of the chip. )
Harvey

Hanson

Very good experience to share with other fellow photographers. Thank you. I have both kinds of camera with the two kinds of viewfinder. I am not so sure or so aware of the alignment issue. Hope other uggers can shed some light on it.

hjkarten Loc: San Diego, California

As a followup to the discussion of the other day, I contacted a Physicist friend who is considered a world expert on digital cameras. He is also Editor of Neurophotonics, and has all sorts of credible credentials.

I asked him: "Dear Brian, What is your formal definition of "dynamic range" of cameras? Does it include "tonal range"? EV (Base 2) values? How does it relate to "Bit - depth" of the sensor?
> Many thanks.
> Harvey
>
His reply:
"For me, it means bit depth of the sensor. E.g., 14-bit means 1-16,000 as dynamic range. Cheers, Brian

Brian M. Sxxxxxxxx, Ph.D., FAAAS, FAPS, FOSA Vice-Chair, Department of Neuroscience Associate Editor, Neurophotonics Professor of Neuroscience
& Physiology [I blanked out his last name out of courtesy]
Perelman School of Medicine at the
University of Pennsylvania"

I checked with a few other physicists in the Department of Physics at UCSD, where I am a visiting "Distinguished Professor of Neurosciences (emeritus)", and received the same answer.

best regards,
Harvey

bclaff Loc: Sherborn, MA (18mi SW of Boston)

Well, despite the credentials, that is really sad and wrong.

hjkarten Loc: San Diego, California

Hi Bill, (bclaff)
You're really pretty funny!
Would you be willing to entertain the remote possibility that you are incorrect? Under such circumstances, my first assumption is usually that I am wrong. I then spend as much time as necessary to read about the issue in question.
Regards,
Harvey

TriX Loc: Raleigh, NC

The actual dynamic range of a camera is NOT equal to the “bit depth” or resolution of the digitizer. The THEORETICAL dynamic range of an A/D is 6.02 dB/bit, BUT the actual S/N is always less since it’s bounded on the top end by the MSB of the A/D and on the low end by the shot noise of the sensor, the noise of the amplifier stage and the quantization error of the A/D. While the max value of a 14 bit A/D is 16,348 (84.28 dB) and the min value is 0, the S/N and hence the actual DR will always be less than 14 bits.

DXOMark, which regularly magically reports DRs of 15-16 bits from 14 bit raw files, admits the following from a description of their methodology:

“The light box behind the target features two fluorescent daylight spectrum tubes with a diffuser sheet on top to achieve perfect uniformity on each filter. The luminance is approximately 1500cd/m². The light absorption levels of the filters range from 0% to 99.99% in order to test across a dynamic range of 4 density steps (= 13.3 f-stops — a dynamic range much greater than today’s digital cameras can achieve”

bclaff Loc: Sherborn, MA (18mi SW of Boston)

This might be a cautionary tale for your experts.
Mastering one discipline doesn't necessarily make one qualified in another, even if it seems related.

Think about this.

Imagine that you put a 16-bit Analog to Digital Converter (ADC) in place of the 14-bit one on an existing sensor.

Would you magically get 2 stops more dynamic range? No !

You would simply have 2 extra bits of random information at the low end of each value.

Really, if it were that easy we'd have sensors with 16-bit, 20-bit ADCs, etc.

bclaff Loc: Sherborn, MA (18mi SW of Boston)

FWIW here's a well know article written by a world renounced string theorist:
Noise, Dynamic Range and Bit Depth in Digital SLRs by Emil Martinec

hjkarten Loc: San Diego, California

I fully agree with you about the fallacy of believing that you can extract 20 bits of data from a 14 bit device by hanging a 20 bit ADC on the readout. As TriX has pointed out, DXOMark chronically makes that mistake in ignoring shot noise, etc. They also are even worse in claiming to extract 14.8 bits of data from a 14 bit ADC output! It is widely recognized that noise and pixel ambiguities degrade the signal at several stages of processing (Thank you, Shannon). But we should give DXOMark a chance to defend themselves.
I certainly never suggested any such idea in any of my comments. Lacking the engineering data from the SONY chip-fabrication lab, we have to assume that they also know how to evaluate chip noise and validity of bit values. If they claim it is a 14 bit sensor, we should knock off some of the accuracy of the readout and grant them 13 bits of relatively clean output. If you want to express that in EV values, I'll yield if it more readily conforms to your preferred manner of reporting the data. Please spare me a lecture on conflagrating EV and bit-depth. I'm trying to reach a point of mutual agreement.
I will try to read the Martinec article, but I won't have time until Friday afternoon. And I will admit that I expect it to be over my head, as my knowledge of string theory is zero. I used up my allocation of uncommitted time this afternoon trying to track down the history of EV values.
regards,
Harvey

hjkarten Loc: San Diego, California

Dear TriX,
Many thanks for your note of clarification. My first effort to send you a reply was lost. I partially responded to your note in my latest response to bclaff.
Yes, I am fully aware of the loss of data in sensors as well as in ADCs, noise in the sensors, ADC, etc. There is always some simplification when writing postings on bulleting boards for general audiences. This discussion is probably grating on the patience of people who just want to enjoy reading about how to best improve their photos.

To address your accurate note: In my lab work I always assume the worst possible result of precision versus validity of data. I spent most of my professional life struggling with the boundary between the nominal output of a device and the valid output after accounting for noise and quantizing errors. I have spent my life fighting repeated battles with S/N. I generally lop off the values generated by the highest bit, and for my 12 bit detectors assume that the system is marginally credible for values of 10+ to 11 bits.
Thank you again for your note.
Harvey