At all iso settings! How? I've not seen anything else keep it's dr when the iso goes up to 6400.
Of course it's not at all ISO settings. It's at base ISO 100. MF marketing and truth is not always very well combined.It's on Youtube so must be true ;D
Of course it's not at all ISO settings. It's at base ISO 100. MF marketing and truth is not always very well combined.
Not that I'm in the market for one. But isn't the sensor size a bit of a let down, does it not play into the hands of the 35mm brigade.
If the physical size of the sensor is what gives MF the look, making it smaller kind of dilutes the reason for shooting MF?
Not that I'm in the market for one. But isn't the sensor size a bit of a let down, does it not play into the hands of the 35mm brigade.
If the physical size of the sensor is what gives MF the look, making it smaller kind of dilutes the reason for shooting MF?
Not that I'm in the market for one. But isn't the sensor size a bit of a let down, does it not play into the hands of the 35mm brigade.
If the physical size of the sensor is what gives MF the look, making it smaller kind of dilutes the reason for shooting MF?
We have a lot of happy P30+, P21+, IQ140, Aptus II 8, Aptus II 6 shooters. All of which are the same size sensor as the IQ250.
Not that I'm in the market for one. But isn't the sensor size a bit of a let down, does it not play into the hands of the 35mm brigade.
If the physical size of the sensor is what gives MF the look, making it smaller kind of dilutes the reason for shooting MF?
At all iso settings! How?Because they have implemented ISO-as-metadata?
One can take these hard-DR claims of 14 stops.Edmund, all the above refer to DSLRs… Usable vs. captured DR is much more with CCD MF if compared with DSLRs... we just have to wait and see if this new Cmos sensor behaves like a DSLR or like MF or is some ware in-between the two… Certainly, 14 stops refers to captured DR... usable DR will be less than that and it will be different between photographers too (as with any other camera) depending on each individual's idea of "correct" development.
2. Lose a couple of stops at the bottom to noise, defects, unbalanced readouts, pattern noise due to stitching and other issues
1. Lose a stop at the top to non-linear effects
You now have a "real DR" of 11 stops. Of which
1 Lose a stop to balance lighting
1 Lose a stop to ISO to get decent shutterspeed
So by now you're at 9 "real" stops, you need 8 for an image, so you have a chance to get a couple of stops of shadow lift with some sensor noise, or to go 1 1/2 stops into the highlights with some tint changes due to non linearity-one of these will work well, the other a bit less, depending on exposure.
As anyone knows, 10 bits is the absolute minimum for a digital camera, 12 is usable and 14 is good - not extraordinary.
This back has a breakthrough feature -Live View- and decent quality. It's a hex wrench to add to the screwdrivers which are already in the toolkit.
And yes, the sensor has another breakthrough feature, probably: Price. But Phase is keeping this detail under wraps, while Pentax is publicizing it :)
Edmund
Edmund, all the above refer to DSLRs… Usable vs. captured DR is much more with CCD MF if compared with DSLRs... we just have to wait and see if this new Cmos sensor behaves like a DSLR or like MF or is some ware in-between the two… Certainly, 14 stops refers to captured DR... usable DR will be less than that and it will be different between photographers too (as with any other camera) depending on each individual's idea of "correct" development.
Edmund, all the above refer to DSLRs… Usable vs. captured DR is much more with CCD MF if compared with DSLRs... we just have to wait and see if this new Cmos sensor behaves like a DSLR or like MF or is some ware in-between the two… Certainly, 14 stops refers to captured DR... usable DR will be less than that and it will be different between photographers too (as with any other camera) depending on each individual's idea of "correct" development.
Hi,
Much of the discussion is nonsense. Increasing ISO is just underexposure. On some cameras it is possible to eak out some more detail in the shadows, by amplifying the signal before AD conversion, Canon does this.
You can expose to protect highlights, but that is done best at base ISO.
Now when you underexpose you can do two things. Either you can tag the raw data with ISO number and do nothing, probably the correct way, or you can multiply the raw data by ISO/base ISO that makes raw files look good but is otherwise a bad thing, IMHO.
If you underexpose you will loose shadow detail, and DR will be reduced and noise will go up. It could be argued that you can protect extreme highlights by underexposure, but you can do that by shooting at base ISO and just get a decent histogram.
This stuff about MFDBs and DSLRs is just marketing BS. The IQ 250 uses a Sony sensor with Sony ADC:s, every bit of the information in that raw file is coming from Sony.
Phase one can do some tricks, like increasing integration times and add an excellent processing pipeline, but they cannot circumvent physics.
Best regards
Erik
If you underexpose you will loose shadow detail, and DR will be reduced and noise will go up. It could be argued that you can protect extreme highlights by underexposure, but you can do that by shooting at base ISO and just get a decent histogram.
With the Sony chips at base ISO and at least 2 stops up in ISO you have a much better range of shadow detail when you underexpose for highlights. I see this all the time with the D800 files. Do you see it with the A99? The trade off seems that when pushed for higher ISO the D800 seems to fine till 3200 past that and the files fall apart pretty quick. Once the raw files from the IQ250 become more available it will be most interesting to see what the ISO range of 400 to 3200 looks like at full resolution.
Paul C
I am not sure I was clear. In my experience the Sony chip just has more headroom at base ISO. So if you are working in extreme light you can easily underexpose to hold te highlights from being blown. I post the same file will easier push 2 to 2.5 stops in the shadows. I saw this with the initial reviews of the D800 on this site and others. The same underexposure with other cameras CMOS or CCD produced excessive noise in the shadows creating the need to bracket for exposure. This ability was important enough to me to invest in a Nikon heavily and the results have been worth it.
I am assuming the IQ250 will have a similar ability.
I use Capture One for Phase files and LR and CI on D800 files. However I tend to lead with LR on D800 files as I don't like the stock camera profile phase has for the D800.
Paul C
Hi,No they are not! …Remember the files Sinn posted in comparison to his Credo back… It's the same with my D800E and (less so) with my D4… Low lights does keep information but colour falls apart developing colour casts… CCDs are much better when you "dig" for info in the darks… That's why I insist on the difference between DR that sensor records and usable DR… OTOH, you compare things while you insist to use LR to develop P45+ files… nobody else does that!
The Sony chips (D800, IQ-250, SLT 99 etc.) have in common that the darks are very clean.
No they are not! …Remember the files Sinn posted in comparison to his Credo back… It's the same with my D800E and (less so) with my D4… Low lights does keep information but colour falls apart developing colour casts… CCDs are much better when you "dig" for info in the darks… That's why I insist on the difference between DR that sensor records and usable DR… OTOH, you compare things while you insist to use LR to develop P45+ files… nobody else does that!let me translate... "usable DR" is a subset of "DR that sensor records" where photon noise dominates and bigger dies of MFD cameras have an advantage just because of that, move deeper where readout associated noise dominates and you conveniently exclude that from your "DR"... card cheaters used to be beaten with candelabras, so that you know.
let me translate... "usable DR" is a subset of "DR that sensor records" where photon noise dominates and bigger dies of MFD cameras have an advantage just because of that, move deeper where readout associated noise dominates and you conveniently exclude that from your "DR"... card cheaters used to be beaten with candelabras, so that you know.Bad translation… ??? "usable DR" simply means what is left after you process an image so that the print has a realistic look… Although it has a different meaning to individuals, everybody can understand the extremes of what a "dull" print is and what a "punchy" print is… "CCDs have more usable DR" simply means that one can retain much more of the recorded DR and still be able to have a "realistic" look… 8)
No they are not! …Remember the files Sinn posted in comparison to his Credo back… It's the same with my D800E and (less so) with my D4… Low lights does keep information but colour falls apart developing colour casts… CCDs are much better when you "dig" for info in the darks… That's why I insist on the difference between DR that sensor records and usable DR… OTOH, you compare things while you insist to use LR to develop P45+ files… nobody else does that!
No they are not! …Remember the files Sinn posted in comparison to his Credo back… It's the same with my D800E and (less so) with my D4… Low lights does keep information but colour falls apart developing colour casts… CCDs are much better when you "dig" for info in the darks… That's why I insist on the difference between DR that sensor records and usable DR… OTOH, you compare things while you insist to use LR to develop P45+ files… nobody else does that!
CCDs are much better ...Once again you are comparing sensors that different in multiple respects:
Once again you are comparing sensors that different in multiple respects:Try to read the phrase rather than a few words out of it…
- CCD vs active pixel CMOS
- larger vs smaller sensor
- different CFA designs, likely aimed at different priorities of the target users (35mm and MF) as Doug Peterson has nicely discussed in his recent article at this site: Read ... (http://www.luminous-landscape.com/essays/the_phase_one_iq250_cmos_fully_realized.shtml)
and sometimes
- different lenses, shutter speeds, effective aperture sizes (affecting out-of-focus and diffraction effects)
Strangely, the same comparison have on occasion been used (even by the same people!) to argue for different conclusions:
- CCD vs CMOS is the sole reason for the difference.
- Format size is sole reason for the difference.
With respect to "usable dynamic range", there are simple physical reasons why a larger sensor with slightly lower engineering dynamic range can still have better handling of shadows at all but extremely deep shadow regions: in moderately deep shadows at low ISO seeds (say two to four stops below mid-tones, maybe five to eights stops below full well exposure) the signal-to-noise ratio is dominated by photon shot noise rather than sensor dark noise, and then the larger sensor has a natural advantage through gathering more photons, whereas engineering DR only looks at sensor dark noise, not shot noise.
Once again you are comparing sensors that different in multiple respects:
- CCD vs active pixel CMOS
- larger vs smaller sensor
- different CFA designs, likely aimed at different priorities of the target users (35mm and MF) as Doug Peterson has nicely discussed in his recent article at this site: Read ... (http://www.luminous-landscape.com/essays/the_phase_one_iq250_cmos_fully_realized.shtml)
and sometimes
- different lenses, shutter speeds, effective aperture sizes (affecting out-of-focus and diffraction effects)
Strangely, the same comparison have on occasion been used (even by the same people!) to argue for different conclusions:
- CCD vs CMOS is the sole reason for the difference.
- Format size is sole reason for the difference.
With respect to "usable dynamic range", there are simple physical reasons why a larger sensor with slightly lower engineering dynamic range can still have better handling of shadows at all but extremely deep shadow regions: in moderately deep shadows at low ISO seeds (say two to four stops below mid-tones, maybe five to eights stops below full well exposure) the signal-to-noise ratio is dominated by photon shot noise rather than sensor dark noise, and then the larger sensor has a natural advantage through gathering more photons, whereas engineering DR only looks at sensor dark noise, not shot noise.
Hi,
"Synn" just tested Capture One's IQ-250 profiles on his Nikon D800 files with good results. That may indicate that camera profiling plays a significant role.
Best regards
Erik
"Synn" just tested Capture One's IQ-250 profiles on his Nikon D800 files with good results. That may indicate that camera profiling plays a significant role.Skill in color science at all stages does seem to be an important factor too -- though with raw conversion as with CFA design, some differences could be due to different priorities in the design of the raw conversion software.
Erik
Hi,It seems that my suggestions work a bit… I wonder why you don't try some I've suggested to you Erik...
"Synn" just tested Capture One's IQ-250 profiles on his Nikon D800 files with good results. That may indicate that camera profiling plays a significant role.
Best regards
Erik
Skill in color science at all stages does seem to be an important factor too -- though with raw conversion as with CFA design, some differences could be due to different priorities in the design of the raw conversion software.
I am interested to see how skillful Sony has been in adapting its CFA designs to the different priorities of "larger format" digital cameras. (Aside: "larger format", because "medium format digital" is a bizarrely inaccurate description of the sensor sizes compared to other digital options!)
Hi,Sinar is using Dalsa sensors on all their current backs… (for some reason all keep forgetting Sinarbacks in this forum). Leica group (Leica and Sinar) have sensors made from three suppliers, Kodak, Dalsa and Cmosis.
I guess we have to wait and see. Synn's posting indicates that profiles play a major roll. It is odd that he finds that a profile built for a Phase One IQ-250 using a new sensor from Sony gives a better image than one that has been optimised for the D800.
Anyway, it may be that profiling may explain a good part of the purported difference between CCD and CMOS.
I guess that in a couple of days we will find out more. I also guess that Phase One's profiles for the IQ-250 will be tuned when more images have been analysed.
Now, we may keep in mind that we have three vendors of sensors in MFD:
- TrueSense, the company formerly known as Kodak delivering sensors to Leica, Pentax and Hasselblad
- DALSA, delivering sensors to Phase One and Leaf
- Sony delivering to Phase One, Hasselblad, Pentax and perhaps also Leica (?)
Each company may offer different CFA designs?
Best regards
Erik
Hi,
I guess we have to wait and see. Synn's posting indicates that profiles play a major roll. It is odd that he finds that a profile built for a Phase One IQ-250 using a new sensor from Sony gives a better image than one that has been optimised for the D800.
who says they were optimized ? why do you think they were interested to provide the best possible for D800 which somewhat eats into their market ;D
Now, we may keep in mind that we have three vendors of sensors in MFD:
- TrueSense, the company formerly known as Kodak delivering sensors to Leica, Pentax and Hasselblad
- DALSA, delivering sensors to Phase One and Leaf and Hasselblad, for its 60MP backs
- Sony delivering to Phase One, Hasselblad, Pentaxand perhaps also Leica (?)(no sign of Sony MF sensors for Leica yet, just speculation)
Each company may offer different CFA designs?
Erik, two slight modifications to your list, an some comets in italics:
Update: The IQ 250 profile makes the awful skintones from a Canon 5D Mk III look better too.it's because they've "worked" (due to the IQ250) on the over saturation that Cmos sensors have…. The blue cast that is developing with your D-800 when you "dig" in the shadows, is most probably because there is excessive colour information intentionally "packed" into the shadows to look like there is more DR than there should be… That's why I say that CCDs have more usable DR.
The Nikon D800 files look nicer after this, but the Canon ones are definitely losing their waxy, global look after this.
it's because they've "worked" (due to the IQ250) on the over saturation that Cmos sensors have….
Hi Theodoros,
CMOS sensors do not oversaturate, they just capture photons. Could you explain what you are referring to (preferably with some authoritative references, if any), maybe something got lost in translation?
The technology differences between CCD and CMOS have nothing to do with color rendering, only with storage of photon affected electron charge, and how it's read out. Any color rendering related differences are only due to Bayer CFA design, Raw conversion, and profiling.
Cheers,
Bart
Hi Theodoros,
CMOS sensors do not oversaturate, they just capture photons. Could you explain what you are referring to (preferably with some authoritative references, if any), maybe something got lost in translation?
The technology differences between CCD and CMOS have nothing to do with color rendering, only with storage of photon affected electron charge, and how it's read out. Any color rendering related differences are only due to Bayer CFA design, Raw conversion, and profiling.
Cheers,
Bart
Bit resolution as no importance ? No matter if it is 8 bits, 10 bits, 12 bits 14 bits or 16 bits ? Surprising.
Today sampling is either 14 bit or 16 bit. Noise floor has not yet passed 14 bit. MFDBs had 16 bit sampling when noise floor was still at 12 bit, and marketing claimed it was an advantage, ignoring read noise levels. Most (not all) has left this fraudulent marketing though and now just talk about the dynamic range, which is based on actual measurements of signal to noise ratio.
Still the quality and shape of noise is one of those hard-to-measure aspects that can affect subjective image quality. Random smooth noise is good, blotchy patterned noise is bad, but in a signal-to-noise ratio measurements these qualities will not be measured. A camera with higher engineering DR can have less useful DR due to this.
I haven't seen any recent comparisons of noise quality out of a recent CCD back and a recent sony CMOS sensor so I don't know if there are any differences there or not. It would be interesting to see. I'm not excluding the possibility that noise quality is visibly different in a typical CCD architecture compared to a typical CMOS architecture.
But I still find it much more likely that these days when comparing a Dalsa CCD with a Sony Exmor CMOS it's all about the CFA and profiling. In other words I would not dare to claim that CCD has some special quality just because it's CCD, I believe that's like the "16 bit myth" it's a work of MF marketing to differentiate from smaller formats, and CCD vs CMOS was simpler to talk about than differences in CFA design and profiling. That language will probably change now when we get the first CMOS MFDBs.
| (http://echophoto.dnsalias.net/ekr/Articles/MFDJourneyEOY/Noise/Histograms/P45+_vsmall.jpg) | (http://echophoto.dnsalias.net/ekr/Articles/MFDJourneyEOY/Noise/Histograms/SLT99_vsmall.jpg) |
Hi Theodoros,Hi Bart… it's just that I have that opinion (which I can't prove - none can), that A/D converters are "tweaked" so that they don't provide a linear output of the (linear) analog input of photons… I believe that the (raw) output is a "linearised S-curve" other wise measurable DR would have never improved to todays values… I believe that Cmos sensors of DSLRs amplify the LLs and restrict the HLs (possibly in the A/D conversion process that is build in to Cmos sensors) to look like they have extended DR than CCDs… My suspicion is that this the reason why with CCDs you have usable DR (on a realistic print) that is very close to the maximum of the recorded DR, while if one tries to print as close as possible to the full extension of the recorded DR on a Cmos sensor, he ends up with a dull (unrealistic) print and with false (cool) colour casts in the darks and (warm) in the HLs...
CMOS sensors do not oversaturate, they just capture photons. Could you explain what you are referring to (preferably with some authoritative references, if any), maybe something got lost in translation?
The technology differences between CCD and CMOS have nothing to do with color rendering, only with storage of photon affected electron charge, and how it's read out. Any color rendering related differences are only due to Bayer CFA design, Raw conversion, and profiling.
Cheers,
Bart
3 lengthy pages about the 14 stops DR of the IQ250... although there is not a single RAW file of the IQ250 available yet.
.. it's just that I have that opinion (which I can't prove - none can) that A/D converters are "tweaked" so that they don't provide a linear output of the (linear) analog input of photons… I believe that the (raw) output is a "linearised S-curve" other wise measurable DR would have never improved to todays values… I believe that … My suspicion is that ...In summary, you state a list of beliefs based on nothing and contradicted by well-known properties of ADCs, simply because you are unaware of (or in denial about) the well-know reason why new CMOS sensors have significantly better "engineering dynamic range" than CCDs. Which is that modern active pixel CMOS sensors have far lower dark noise levels than the best modern CCDs: about 2 electrons (RMS) vs about 10-12 for those CCDs. You can read this in spec sheets at Truesense, Dalsa and so on.
….a list of beliefs based on nothing….Nothing? ….I (and many others) find CCDs to have much more usable DR on prints than Cmos (as I stated on my reply to Bart)… But again, I only print about 8 square meters a day on year average… MO is simply based on (photographic) findings… which are the only ones that matter ...to photographers.
No thread stays on topic for more than one page or so anyway ;):)
Nothing? ….I (and many others) find CCDs to have much more usable DR on prints than Cmos (as I stated on my reply to Bart)… But again, I only print about 8 square meters a day on year average… MO is simply based on (photographic) findings… which are the only ones that matter ...to photographers.I was referring to your stated beliefs about ADC's in CMOS sensors being tweaked to producing non-linear responses,and declare that this is the only possible explanation of the improvement in total DR given by CMOS sensors.
I was referring to your stated beliefs about ADC's in CMOS sensors being tweaked to producing non-linear responses,and declare that this is the only possible explanation of the improvement in total DR given by CMOS sensors.I was referring to results… 8) ...that don't coincide with scientific theories. ::) and thus, expressing a suspicion that my conspicuous mind finds to be an explanation… ;) …if I have your permission of course. ???
I wil say it yet again: these "CCD vs CMOS" DR comparisons are mostly sensor size comparisons: they reveal the genuine advantages of a _larger_ sensor that can gather more light (count more photons total across the image) when fully exposed (base ISO speed, ETTR etc.), which gives a better ratio of signal to photon shot noise, and thus a better SNR in the relevant parts of most images, and so more "usable" dynamic range, even when compared to a smaller sensor with higher engineering dynamic range due to a far lower noise floor. Engineering DR is only of much relevance to photosites that get far, far less than full-well illumination, more than ten stops below saturation. Such low light levels are mostly relevant to (a) high ISO, low light photography, and (b) gear-heads who seek out extreme cases as reasons for wanting to pull details out of shadows way, way darker than are usually relevant.
Short version: photons shot noise is becoming progressively more important than dark noise or read noise, and so engineering DR is becoming less relevant as a measure of sensor performance, except in low light situations.
I was referring to results ... that don't coincide with scientific theories.The results you see conform perfectly with scientific theory, as I explained in my last post: larger sensors that can count more photons have a better ratio of signal to photon shot noise and thus better signal-to-noise ratio when given full exposure (base ISO speed), whereas total dynamic range only tells you about noise levels in the deepest shadow regions, about ten stops or more below saturation level, which is the only place that dark noise is significant compared to photon shot noise in modern sensors.
The Aptus is very slightly better than the D7000 down to about 7 stops from saturation (max 1/3 stop better if even that), then read/dark noise becomes a factor and the D7000 wins with about 2/3 stops towards the noise floor.The MF camera there is from 2005, so more recent MF models should perform a bit better, with the far bigger CCDs staying ahead of the smaller Sony EXMOR CMOS sensors for more than the top 7 stops, but the overall pattern is probably the same.
The results you see conform perfectly with scientific theory, as I explained in my last post: larger sensors that can count more photons have a better ratio of signal to photon shot noise and thus better signal-to-noise ratio when given full exposure (base ISO speed), whereas total dynamic range only tells you about noise levels in the deepest shadow regions, about ten stops or more below saturation level, which is the only place that dark noise is significant compared to photon shot noise in modern sensors.Have you ever tried an old MFDB with 6 or 11mp 24x36mm sensor? ….Obviously not!
But apparently you prefer to ignore that explanation, just as others want to ignore differences in CFA design and other aspects of color handling, and instead attribute the differences seen to the difference between CMOS and CCD technology.
P. S. This is nicely explored by torger at http://www.ludd.ltu.se/~torger/photography/noise-test.html as discussed in another thread starting at
http://www.luminous-landscape.com/forum/index.php?topic=86989.msg708619#msg708619
In particular, I quote one of torger's conclusions:The MF camera there is from 2005, so more recent MF models should perform a bit better, with the far bigger CCDs staying ahead of the smaller Sony EXMOR CMOS sensors for more than the top 7 stops, but the overall pattern is probably the same.