Marsu42 said:
unfocused said:
I find this perplexing. Comments on this site and others from 5DIII users have led me to believe that the 5DIII shows some significant improvements over the 5DII in noise levels at higher ISOs. So, when you say the 6D uses "the same tech level as the 5DII/5DIII sensor" which sensor are you talking about?
The sensor hasn't been improved much on the 5d3, but the readout is cleaner (less banding) and the noise has a "nicer" film-like pattern giving it an edge on iso3200+ ... overall it might be a 0.5 stop improvement with a much more usable iso12800, but "significant improvement" isn't the word that comes to my mind here. The improvements of the 5d3 lie everywhere else, but Canon chose to reserve their best current sensor tech for the 1dx.
I can say that because I d/l'ed 5d2 and 5d3 raw studio samples myself (and so should you!), had a look at them in LR and up to iso1600 there is no difference I can see - some even figure that the 5d3 has worse sharpness than the 5d2 due to a stronger aa filter and it does have a bit less dynamic range (not that anyone would notice, but still...).
If people say the 5d3 is the high iso king imho that's because a) Canon marketing owns them, b) you see what you want to believe after paying $3500, c) the subjective impression how much less banding when raising shadows and the film-like noise pattern improves the picture varies among viewers and individual shots.
Last not least: Even if the iso noise on the 5d3 is somewhat improved, this even more shows the limited dynamic range of current Canon sensors that decreases further the higher the iso setting is. Disclaimer: The 5d3 is a great camera and I still didn't get a 5d2 because I still struggle with myself if I am willing to pay €3000, but the 2 stop improvement Canon predicted is a fairy tale.
Even according to DXO, the 5D III's DR and noise at HIGH ISO is better, even than the D800. The 5D III only loses ground at LOW ISO, in the ISO range 100-400, where read noise starts eating away STOPS worth of shadow DR. The "quality" of read noise has improved...there seems to be less banding in one direction, with roughly the same in the other direction, so lifting shadows is not as bad as it was before despite the fact that the 5D III has slightly less DR than the 5D II AT LOW ISO. When it comes to High ISO, though, you are ultimately limited by physics. The reason differences in DR across multiple camera brands all normalize in a near-linear faloff curve beyond ISO 400 is because your approaching physical limits. The 5D III fares better at high ISO because it has a higher S/N at those settings (thanks to a weaker CFA, which affects native color fidelity for the tradeoff of higher per-pixel Q.E.)
Noise quality at high ISO is also determined by physics. The random "grainy" nature of 5D III ISO is primarily driven by the physical nature of light. It has far less to do with the electronic makeup of the sensor itself. Lower read noise might help the nature of noise at ISO 800, maybe ISO 1600 (MAYBE), but at high ISO, statistically speaking, the 5D II, 5D III, 1D X, D800, D600, etc. should all pretty much exhibit THE SAME kind of noise for an identical scene...as the hardware at ISO 1600+ really has very little to do with noise characteristics.
unfocused said:
Marsu42 said:
jrista said:
I would only disagree that the 6D IQ will surprise people...unless those people actually expect it to be much better than any other Canon sensor. Canon has not yet demonstrated an improved manufacturing process, so it is doubtful that the 6D sensor will be radically changed in any way.
The Canon exec in the Photokina interview in some other thread already stated that the 6d sensor uses the same tech level as the 5d2/5d3 sensor, so there won't be any positive surprises here - it's really a 5d2 in a smaller 60d-like body updated to current manufacturing processes like digic5.
I find this perplexing. Comments on this site and others from 5DIII users have led me to believe that the 5DIII shows some significant improvements over the 5DII in noise levels at higher ISOs. So, when you say the 6D uses "the same tech level as the 5DII/5DIII sensor" which sensor are you talking about?
Canon's sensor technology has improved marginally, and basically as little as it possibly could, since the 5D II and original 7D. To achieve any improvement at all while remaining on the same old 500nm fabrication process, Canon effectively had to "cheat". They improved low-ISO noise quality a little by improving S/N overall. They improved S/N overall by improving Q.E. They improved Q.E. by REDUCING the strength of the color filter array (CFA) in the sensor...the red, blue, and green color filters over each pixel. A lower strength CFA allows more light through, but also increases color crosstalk among pixels. Red pixels are now more red-green. Blue pixels are now more blue-green. Green pixels are now more Green-sortaRed-sortaBlue. It's a cheat...a means of extending the life of a very old CMOS fabrication process. It is actually quite amazing Canon has strung a 500nm process along this far, but they really can't extract all that much more out of it, if anything, at this point. The 6D sensor is still being fabricated on the same process as the 5D III sensor, which is the same process as the 5D II, and even the 5DC, the 7D, the 60D, 50D, 40D, etc. dating back to the early 2000's.
So, no...the 6D sensor will not really bring any kind of major sensor fabrication improvements to the table. Canon has experimented with and prototyped sensors on a 180nm Cu wiring fabrication process. Their 50mp APS-H and the 120mp APS-H both used a 180nm process. They have prototyped 180nm sensors that make use of high refractive index lightpipe technology for higher Q.E. that approaches the performance of BSI sensor designs. Based on the 120mp press releases, it even sounds like they have some kind of CP-ADC technology. But they have not yet put any commercial-grade high-volume sensor fabrication on those processes yet (god only knows why...if they don't do so soon, they will really be in a competitive bind.) Regardless, it is highly, highly doubtful that the 6D will offer any kind of major IQ improvements over anything on the market today, and it most likely will use the same 500nm process as every other Canon sensor released in the past decade.