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What would the FFF have to do in order to be competative?

Started 1 month ago | Discussions thread
Scottelly
Scottelly Forum Pro • Posts: 18,026
Re: What would the FFF have to do in order to be competative?
1

abera wrote:

Scottelly wrote:

abera wrote:

Scottelly wrote:

abera wrote:

dellaaa wrote:

Reading a recent post that included a 60M pixel Bayer sensor shot, the the discussion turned into a debate as to whether the FFF would ever arrive.

Looking at the Bayer photo what do you believe the FFF sensor would have to do better than the current generation of Bayer sensors? What are the design criteria the FFF design team have?

I don't know but given the physics of the design and the past Foveons, low light performance would most likely not be on par with the Bayer, agreed?

Foveon has three photodiodes per pixel, none with correlated double sampling. This means very high read noise which means high noise floor which mean poor performance in areas with little light. This means poor low light performance and relatively low dynamic range.

If that's the case, then why did early Foveon sensors have so much more dynamic range than the Bayer pattern CFA sensors of their time?

Did they? Can I see some measurements proving it? I have never seen any.

The issue with read noise can not really be solved

Why not?

Two reasons:

Three photodiodes per pixel instead of one. This alone means sqrt(3*n^2) of noise per pixel compared to single photodiode.

The other is practical impossibility of CDS.

- there will naturally be more photodiodes, but also CDS is quite impossible to achieve with this kind of design.

What is CDS?

Correlated double sampling. It's used to eliminte the main pixel read noise element, the reset noise. With the Foveon vertical pixel structure it's hard to see this happening.

Some fancy non-destructive multiple sampling might be possible but it would not only slow things down even more, but also not be as effective.

From QE point of view the advantage of Foveon is not having colour filter array blocking light, but on the other hand there is plenty of dead space between the photodiodes. I'd guess one might be able to achieve slightly larger QE with Foveon which would help somewhat in low light situations, but not with the noise floor itself.

Historically, Sigmas have required extensive image processing both while taking the shot and afterwords (SPP). Will the FFF shoot at the frame rates of the current Bayers? Again, given the history, this seems doubtful.

Foveon's problem is the very poor color separation.

Huh? I thought it was supposed to be noise that was Foveon's "problem."

This was in the context of the paragraph.

Read noise isn't really a big problem for most photography as the maximum dynamic range is rarely needed (especially for JPG shooters it's quite irrelevant). Though for low exposure photography (e.g. hand held low light) this is an issue.

Color separation issue is on the other hand always there.

Foveon separates colors by taking advantage of the fact that different wavelengths of photons tend to be absorbed at different depth in silicon - the problem is that this is not a deterministic process, but a probabilistic one making the color separation very weak.

Also the photon absorption is quite a bit top heavy - as you know Sigma made the two bottom layer photodiodes four times the size of the top layer (areawise, depthwise they are also much larger). There is a reason for it - the bottom layers are simply relatively photon starved. Additional benefit is reduction in total read noise. It also indicates the difficulty of increasing the resolution of the bottom layers from image quality point of view - I think this is a good compromise even though it's a deviation from the original design, increases SNR somewhat with neglible resoltution loss, though maybe opens the door slightly to false color artifacts.

In principle this could be helped by placing narrow band color filters on top of the sensor, but then some wavelengths would be totally lost and could cause some interesting artifacts.

To get decent color out of Foveon the processing indeed will be rather strong - this increases noise for color photography.

Where do you get this idea?

From the weak color separation.

Page 177 of this . Note the spectral sensitivity chart and the color matrices.

So with low light and speed out of the equation, whats left, detail and color rendition.

The main advantage is reduction in false color artifacts (e.g. moiré). This advantage goes away once diffraction (and lens deficiencies) does anti-aliasing, but it's still a long way from today.

Detail situtation has many variables, but regardless of them lots and lots of pixels would be needed in this hypotetical FFF to compete.

Color accuracy is vastly better on conventional sensors. That's why the CFA is there for.

Wrong. The Quattro generation was one of the most color accurate sensors of its time.

Wrong. From the above document:

One does not get more accurate colors from exremely weak color separation. One gets less accurate colors with more noise.

Technology has moved on, but for the money you probabky coukdn't get a camera with a more color accurate sensor than a Quattro.

Likely all conventional Bayer CFA cameras have more accurate colors from hardware point of view.

Well if that is true, then you're saying Sigma knows how to coax better color out of sensors than Nikon.

No they can't.

I find that hard to believe, but I guess it's possible. There have been several fp L users here who have multiple systems, and they prefer the colors they get from their Sigma cameras.

Sure, but that's a personal preference, not accuracy thing.

All the camera manufacturers try to create JPG colors which sell cameras, thus they don't go for accuracy, but for pleasant output. Typically different manufacturers have a different idea on what sells, thus you have Nikon colors, Canon colors, Fuji colors etc.

The point here was image sensor and it's capability to create accurate colors.

Well without processing the raw data you get nothing but a bunch of raw data. I know of several professional photographers who prefer to use one raw processing program vs another because of the colors they get in their images with the program they prefer (i.e. Lightroom vs Adobe Camera Raw, or Capture One vs Lightroom). Obviously that has nothing to do with the sensors' capabilities, but it's still very important to photographers . . . probably more important than the capabilities of their sensors.

To get accurate colors, the JPG engine (in camera or raw-converter) is typically calibrated with light from a couple of different spectrums and if one were to shoot in a similar (or the same) light, one can expect very accurate results. Change the light and that's where the challenge is.

Well, the Quattros tend to have better results with auto white balance than Sony cameras of comparable age and price. Of course that has more to do with firmware than sensor capabilities, I'm sure.

The better quality data one gets to work with, the better quality the output can be -

And "can be" is the key here. It seems to me that Sigma tends to have a very good handle on the "can" part, while other companies tend to be about the same as always, or in some people's eyes, worse than in the past. Lately I've heard a lot about "color science" (not that I think a camera's in-camera processing is all that important), and Fuji seems to be getting talked up a lot lately. Maybe Sigma will fing itself in a similar position at some point.

when the color separation is very weak, the data has low quality information.

Well if that doesn't matter, because the camera or raw development software can perform miracles with the "bad data" from the sensor, then who cares?

Essentially it's about SNR on chrominance information.

Other small companies have been known for their color too, such as Leica, Hasselblad, and Phase One.

Foveon type multi layer system might work better in the future with different materials, maybe organic materials or perovskites. Plenty of perovskite developement is being done due to their potential for solar cells and at least one multilayer demonstration does exists (with hideous image quality). Maybe 15 years from now?

As for detail, how would the specs of the proposed FFF stack up against the 60M plus Bayer sensors? Would the advantage in detail make up for the shortcoming?

No. You need likely something like 70% of the pixel count to match conventional sensors, maybe more nowdays as AI-based demosaicing is on its way. This also diminishes the false color advantage.

Anyhow, as even 10MP is enough for very large prints...

The remaining design criteria, is color. Would Sigma's color rendition be enough for people to buy it?

Some like it's different colors and I'm sure many fans would buy because of them, but as the colors can be very problematic and lack in accuracy and because the conventional cameras are not exactly lacking in color accuracy, it's hard to see how the general public would get interested in this.

I don't know and would like rational, opinions as just what will the FFF bring to the table, and why any non L mount people in 2023 would buy it when 100M pixel Bayers are on the horizon that take great low light picture at high frame rates.

At this point, fanboys aside, the fact that we are still discussing this seems a bit absurd to me, so why did I start this thread lol?.

Foveon is very interesting concept and I'm happy it was brought to life. But it feels more like a hobby project, a niche project for those who desire something different. There aren't really any advantages over conventional sensors

Huh? You already gave one in your own reply here above . . . "The main advantage is reduction in false color artifacts (e.g. moiré)."

I said "really any advantages" - meaning that there aren't much relevant advantages. But I can agree that I should have used more careful wording.

As long the the sampling rates of conventional sensors are low enough for diffraction (and lens flaws) to not be enough to eliminate false color artifacts, this can be a small advantage.

Of course it could esily be corrected by using strong enough anti aliasing filters, but since pixel peeping is part of camera reviews and those sell cameras, AA-filters are now largely gone or very weak (and often unidirectional as well.

while the drawbacks may cause issues.

I hope a FF Foveon does see the light of day, but not only I'm not holding my breath, I'd expect the product to be a very low volume very high price item.

Of course the first FFF will be low volume and high priced, but for all we know Sigma will make a future generation in ten times the volume

How? In order for Sigma FFF be a large scale products it would need to have tangible advantages without tangible disadvantages. This is not the case. Also it would need to offer similar marketing (including indirect marketing like camera clubs, peer pressure etc.) and support networks, camera shop visibility and so on. There is no reason to believen any of this will happen.

There have been many products put on the market, which dominated a niche in their industry without a large support network or a significant marketing presence. The product just has to work well. Today, with the Internet, that is even more likely, because of how easy it is for people to find the information.

...and disinformation

There is very small market for "different" cameras which have practically no advantages over conventional cameras.

Tell that to the professional photographers who pay thousands of dollars extra to buy cameras that work slower, weigh more, and are harder to use . . . you know, those "niche" market cameras, like Phase One, Hasselblad, and even Fuji GFX cameras, which require those big, slow, heavy, and expensive lenses.

The market shrinks even more if the product is more expensive and underperform in many ways.

Sure, but there is still a market, and it can be quite profitable. Rolls Royce kniws this. So does Ferrari. So does GoPro.

, allowibg them to price it very low, so it sells quite well.

So it will sell well because it's price will go down because it sells well? Something circular in that argument.

No. It will sell well, because its price will be set low by the manufacturer from the beginning, because the manufacturer doesn't need to sell it for such high prices, because it costs less to make, since it is being manufactured in higher volume.

It's a bold assumption that it (i.e. the "second generation FFF") would sell in great numbers (vs. the "first generation FFF") allowing for lower prices, while offering no reason why the sales would go up.

I've already given multiple reasons. Did you forget?

1) Price is lower, because of higher volume of production, so more people buy.

2) Camera provides photographers with medium format image detail in a camera that weighs half as much, and has a huge selection of affordable lenses available.

3) Foveon sensor advantage means that even with the sharpest lenses and the sharpest aperture setting, there is no color moire to deal with.

There are other reasons to buy, but there are reasons to not buy too, of course. That's always how it goes with new camera buying decisions.

For example, I'd like to buy a Fuji X-H2, because it can do 8Kp30, but it can't do 4Kp120, like the Fuji X-H2S, and it has no built-in GPS, like the Canon 5D IV.

The product is and will always be a small niche product - it offers little to no practical advanages, even fewer in the future as diffraction removes false color artifacts (and other aliasing, from Foveon too too), offers several disadvantages, has far less marketing, support, visibility and so on.

Don't get me wrong, I like Foveon, but not because I think it's better, but because it's different.

You seem like a pretty well informed person.

Thank you. I know a bit of some stuff.

It's difficult for me to believe you don't know how this works.

I think I do know. I think I've been quite logical here.

Your comment brings into question your motives, and makes me wonder if you just have an axe to grind. Are you just trolling here?

That's quite childish.

Asking if you're trolling?

To me it seems like you have a emotioinal need to protect Foveon from what you perceive to be an attack on it.

Maybe. I believe in it. I'd protect the U.S.A. the same way if you attacked it verbally, trying to say it isn't really a great country after-all, because I would feel you're confused or just don't know the truth.

Hard to see why you'd go on this road otherwise. Dish me more this and I'll return the favor. Ruins the thread from others though and mods will likele finnish it.

Not really. I don't think that calling someone out for attacking a product that is popular with the majotity of forum members ruins threads at all.

Do you know Sigma's history in the camera world?

Yes, pretty well. Both lenses and cameras. Actually one of my all time favorite lenses is a Sigma - the 1st generation 30/1.4 APS-C lens was splendid for street shooting.

Do you realise they've been selling cameras for about 20 years?

Yes, and frankly you're being quite impolite.

How is it impolite to ask you if you realize something I think you may not know?

If you don't have an argument about the topic, then don't say anything. You don't need to defend the "honor of Sigma or Foveon".

If I don't, then who will? If we let all sorts of people come into this forum and bash Sigma cameras, without defending them, then people who are looking for information, rather than disinformation, could be misled.

Do you know Foveon sensors have been improved time and time again,

Of course - for example the first generation had a read noise of something like 40 electrons if I don't remember wrong, while the most recent ones have cut it well below 10, maybe even below 5.

I wonder if conventional sensors have improved at all...

(The above was of course sarcasm.)

So you admit Sigma/Foveon has improved their sensors in the past. Will you admit that maybe . . . just maybe . . . they will improve them in the future too?

My point is that both Foveon AND CFA sensors (Bayer pattern, X-Trans, etc.) have improved. Not just the sensors made by Sony and other big companies. Many people try to talk down the cameras with Foveon sensors by saying Bayer sensors can make relatively clean images at ISO 6400 and even higher, and I think tjat's great, and shooting at high ISO settings, like ISO 800 and 1600 is one of the reasons I have my Nikon D810, but that only goes so far. It's a small advantage, where most people are concerned, and a big advantage for some, but when most of my photography is done at ISO 100 or 200, having the ability to shoot reasonable quality photos at ISO 6400 really isn't that important. There are lots of advantages of other cameras. The list would be long (battery life, IBIS, speed, etc.). None of those advantages convinces me to not shoot with Sigma cameras though, and in the future Sigma will make even better cameras, which operate faster (like the Quattros vs the Merrills), have tilt screens, better viewfinders, and maybe they'll even have IBIS. Then the CFA cameras will have even less advantage.

and Sigma cameras have continued to offer some of the best quality digital imaging,

Not from the cameras. They have one basic strength - no (or less) false color artifacts compared the CFA sensors without (or with weak) AA-filters.

Well, that translates into spectacular image quality, I guess, and that's enough for me.

The weaknesses are numerous.

Absolutely they are, and in this forum we're well aware of the weaknesses of Foveon sensors. Believe me.

Foveon is a different product and I appreciate it for that, but I don't delude myself into believing that it's an all-a-round superior product.

Neither do I. I think many, if not most of the members here have other brands of cameras too - not just Sigma. Now that Sigma makes cameras with CFA sensors too though, there's less reason for us to own other brands. I look forward to the time when I have just one system of lenses, so I can build that out, and have a really extensive selection of lenses that work with all of my cameras.

The lenses are on the other hand nowdays absolutely stellar. They often used to be quite hideous several decades ago, but in addition to the typical lenses they also often had some options other manufacturers din't have. Slowly the lenses got better and nowdays they're easily among the leading manufacturers when it comes the quality, and if I recall right, the leading when it comes to quality.

against the massive industry for all those years?

They've not been "against" the industry, but part of it.

I'm referring to the competition between CFA and Foveon (if you want to call it that). You're the one who mentioned

I call that amazing,

Why? Sigma is just another corporation among others.

Would you call Canon, Nikon, Sony, Leica, Volkswagen also amazing? They all started from nothing as well and are doing pretty well inspite of competition

and I prefer the images from the SD Quattro H to everything else,

Good for you. But this thread is not about your personal preference.

except a 100 MP (or more) medium format camera,

Wouldn't 99MP be enough? Does it have to be MF - would a 100MP FF be enough?

as do several other photographers here, despite the dynamic range disadvantage,

I feel temptend to ask what you think DR is, but maybe I shouldn't

I guess SNR isn't relevant to you since you did't mention it.

and despite how slowly the Sigma cameras operate. That alone should tell you something.

Sure, you like your camera. You. That's a personal thing. Not an objective statement of performance of some imaging technology.

I have used Canon, Nikon, and Sony cameras (several from each brand), yet I prefer to shoot with Sigma cameras. That's not because I'm stupid, ignorant, or a masochist, but because my Sigma cameras produce better images.

No, it's because you like the results of your Sigma cameras.

For your own sake you should understand that your personal preference is not the same as objective reality.

First it would need to exists - if it will ever exist, the long depelopement doesn't really indicate that the mythological "next generation FFF" following it would be developed fast or that it would have enough tangible advantages when the competition will at that point have 200MP or more and be cheaper than it's predecessor.

When even medium format seems to have stopped moving forward in resolution, what makes you think that will ever happen?

Likely for two reasons - not much competition to push the resolutions up, and also processing/storage needs).

And how will that change over the next few years? It's not like we can't buy a 5 TB hard drive for around $100. I just did myself, because my old 5 TB drive is full.

New image sensors ordered for MF aren't cheap as the sensors are big (yields go down with size - deficient pixels aren't necessarily problems, but for example an ADC would be) and the volume is low.

Sure, but that isn't anything new. It's been like that for the past twenty years.

Have you noticed how mobile phone cameras have now broken the 100MP barrier?

Meaningless. We're talking about ILCs, so mobike phone tech has no relevance, right?

Competition drives things.

EXACTLY! There seems to be no resolution competitiveness in the full-frame workd these days. I don't get it, frankly, but it seems that everyone is happy to leave Sony on top of the World, with regard to high-resolution imaging, though Sigma did seemingly join Sony at the top, using what appears to be a modified version of the same sensor. Leica recently joined in at 60 MP too. Nikon and Canon appear to be happy at 45 MP. This is why I question the thinking that 100 MP is coming to full-frame.

Panasonic just made two new cameras, and were either of them high-resolution, with a sensor that offered more detail capture than their first high-resolution full-frame camera? No. How about what Nikon, Sont, and Canon have put out recently? No.

There are lots of reasons - from marketing, manufacturing, COVID related supply issues and so on.

Well so be it, but COVID is over, and most of the supply issues have been cleared up too. Still we get no announcement from anyone of a camera with a sensor over 60 MP.

If 200 MP sensors are coming, why are there no full-frame cameras from Canon or Nikon with sensors over 45 MP,

Sony has 61, but I guess it doesn't count as it doesn't fit you agenda.

I already mentioned them, so what's this about an agenda? Sony stepped up like three years ago from 42 ti 60, presumably to compete with Nikon's 45 MP Z7 and Panasonic's 47 MP S1R, but since then there has been basically nobody doing anything to step up past Sony. Three years with no response (not even an announcement) seems like they just don't plan to step up past 60 MP.

Why would that be the end? It's kind of hard to sell new cameras if the specs don't improve.

Oh, specs do improve though. More and mire cameras will do 8K video, and they'll get better screens and HDR viewfinders, and they might even start making cameras with GPS and stuff like that. Sony just improved the screen AND viewfinder of the A7r line when stepping up frim the IV to the V. That sort of thing will keep happening. They'll make more stacked sensors too. Nobody seems interested in making even an 80 MP camera though, let alone a 100 MP camera. The megapixel race seems to have ended years ago, and Sony won.

even though Canon made a 50 MP camera years ago, and Nikon made their first 45 MP camera (the D850), which was a DSLR, years and years ago?

There can be a million reasons. But none of them is what you seem to think (i.e. that Bayer CFA cameras has now peaked and will forever remain in this spot and this will bring glory to Sigma and it's loyal supporters.)

For example to use smaller pixels one wants to use finer geometries in manufacturing and their availability is limited.

Ummm . . . years ago Nikon, Sony, Panasonic, and others had the ability to make sensors with a lot more density than we have today in full-frame. They did so with 1" sensors which were 18 MP and 20 MP. To think they couldn't do that today if they wanted to seems like fantasy to me.

Image sensors tend to use fab lines which are obsolete for their original use. I think that one major reason - now this is only my educated guess - for the relative slow progress of increase in pixel counts over the last few years has been because of lack of fabs. Mobile phone cameras, automotive cameras and all other kinds of small pixel cameras need (relatively) fine geometries making them unavailable for larger sensors unless they put up enough cash.

That is all it would take, so the fabs are available - more today than ever.

Considering that (large) image sensors are already by far the most expensive part of the cameras, doubling (or more) it's cost might be a problem.

Increasing density a little would double the cost of the sensor? Please explain your thinking on this.

So I think it's mostly been a manufacturing resource issue. But since small sensor production is no longer skyrocketing (at least the numbers and market studies say so), and have even for a while stalled, more older fab lines should become available for larger sensors at reasonable prices.

So the megapixel race will be back on next year?

https://www.dpreview.com/reviews/sigma-sd-quattro-h/3

I'm not suggesting Sigma will fix all the problems with their in-house sensors, but thise sensors have improved in the past, and I have no doubt they will improve in the future too.

Sure. But the last new Sigma sensor came out when? Do you think Sigma has the resources to compete with the rest of the world - Sony and Samsung and others pour billions after billions into R&D getting constantly not only more refined products, but also all kinds of innovations.

I think there will always be a market for good quality, unique products, which offer something different.

Of course - I don't think I said anything contrary. I think I said something quite similar actually

But if you believe that Foveon sensor is some kind of game changer, I'm afraid you're significantly in error.

Leica keeps making monochrome cameras. That is a niche product, but obviously a successful one, or they wouldn't keep doing it.

Sure - though Leica has extreme brand value which gives them possibility of making that kind of "niche of niche" product. It's also dirt cheap for them as sensor without color filter array isn't any more expensive than one with it - likely slightly cheaper even in relatively low volumes and the revamped image processing is a job of a day or so for a software engineer. (They may have done more, but that's the general idea.)

Anyhow, Pentax is another intereting brand - it seems to become the one last DSLR manufacturer providing a DSLR "difference" in mirrorless world. It likely provides modest but solid income to Ricoh and will likely remain a good little niche.

I believe Sigma will continue to improve on the Foveon sensor, making more "niche" products with them in the future, and differentiating themselves from the competition by doing so.

Sure it's entirely possible and even likely. And i hope so. But it'll never be more than a niche player with this technology and an additional problem is that the relative advantage(s) of this technology get smaller and smaller every year. Also I doubt it'll ever try to go head to head with the big boys as the investments would be significant and the risks large. The competition is stiff and the markets aren't as good as they used to be before mobile phone camera revolution.

Sigma is a leading lens manufacturer. To me the cameras are a love child, a hobby - it's (AFAIK) a privata corporation, so they can afford to have such proyects. I do hope Foveon keeps on being developed and produced just for the sake of uniqueness. It makes the world richer. Though, in time it'll lose the false color advantage fully and then it's just game over. This is not that far away, thus investing heavily in dead-end technology is not likely, even if it is a hobby.

FWIW, here's a link to an interesting image about the vertical structure from Chipworks. The comments by Eric Fossum may be of interest. (EF is the inventor of for example 4T pixel structure commonly used in sensors.)

This might help you understand Sigma cameras:

https://medium.com/ice-cream-geometry/an-ode-to-the-sigma-merrill-506dd0864169

I actually do understand how Foveon sensor works, likely better than the person who wrote that love letter of an article.

I think this thread is getting way too long, so if you reply, I think we need to split this into two or three sections.

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